Oasis Montaj Tutorial_english 606kn

[email protected]

key.

Instant information on the GUI or corresponding Geosoft eXecutable (GX).

A

Application Information

Click the Help ( any dialog (GX).

S

System Information

On the Help menu, select Help Topics to run the Help System. Search the Contents or use the Search Function.

Oasis montaj conceptual, procedural and GX information.

T

Tutorials

On the Help menu, select Manuals and Tutorials.

Oasis montaj Quick Start tutorial and applications and add-on tools manuals, tutorials and selected technical notes are available for online viewing and printing in Adobe PDF format.

) button on

To access technical information for each parameter on the current Oasis montaj dialog (GX).

Tutorial 1: Getting Ready to Work 45

The following graphic gives you a preview of the “S” part of FAST. When you access the main Help system, you see a screen similar to the following:

Advantages of FAST Information Delivery Geosoft’s move from printed manuals to electronic information delivery is pragmatic: • The system has become so full-featured that the optimal solution to providing accurate, brief and complete (ABC) information was to centralize information in a single information warehouse (i.e. the Oasis montaj Help System). • s would be able to print full versions of manuals based on the design and technologies Geosoft was implementing. • Electronic information retrieval is a powerful technique that enables s to take advantage of the computer’s highly optimized searching capabilities. • With over 40 manuals to , manuals were updated infrequently; the new system means that information can be updated and delivered much more rapidly through media such as our web site. • s would have the ability to print partial information or full manuals wherever they were – providing maximum flexibility, reducing the need to keep track of manuals and putting the information at the ’s fingertips. • Deploy resources more effectively as measured in of our s’ ultimate benefit. By transferring resources spent in low-return tasks (such as

46 Tutorial 1: Getting Ready to Work

formatting, producing and distributing manuals) into creating and maintaining information, Geosoft has committed itself to spending its resources to deliver accurate, brief and complete information to its customers.

Printing Complete Manuals on Demand To make sure our s have the latest manuals, we ship electronic versions of selected manuals and tutorials with our Help system. Application manuals and Quick Start™ Tutorials currently available include: • montaj Geophysics (includes 1D-FFT Filtering) • montaj Geochemistry • montaj Drillhole Plotting • montaj Airborne Quality Control • montaj Geophysics Levelling • montaj MAGMAP Filtering (includes 2D-FFT Filtering) • montaj Gravity & Magnetic Interpretation (includes Euler 3D) • montaj Gridknit • montaj Induced Polarization • montaj 256-Channel Radiometrics Processing • montaj Gravity and Terrain Correction • montaj UX-Detect • Target Surface and Drillhole Mapping System • GX Developer • DAP Client Tutorial • DAP Guide In addition, as part of our new FAST strategy, we are allocating resources formerly spent on formatting, preparing and delivering hardcopy manuals on adding more manuals and tutorials to the system and updating the current ones on a timely basis. For the most up-to-date manuals and tutorials visit Geosoft website at http://www.geosoft.com/resources/tutorials/ T O P RINT C OMPLETE M ANUALS 1. On the Help menu, click Manuals and Tutorials. The system displays “The

Online Manuals, Tutorials, and Technical Notes” menu page in your default HTML browser. 2. Click on the document you want to print. The system opens the PDF file for

printing. Note: If the tutorial is not available locally you will be linked to the Geosoft “s” web page. the tutorial of interest from this page. 3. Once the PDF tutorial is opened in your default Reader, click the File|Print menu to print the PDF file.

Tutorial 1: Getting Ready to Work 47

48 Tutorial 2: Working with Data

Tutorial 2: Working with Data Some of the more important components of the system are databases, spreadsheets and profiles. The “window” to the database in Oasis montaj is a specialized earth science spreadsheet that appears automatically when you create a new database. This spreadsheet provides access to a wide variety of data management, data and profile viewing and processing capabilities. The purpose of this tutorial is to give you a general overview of how you can use this data management system effectively in your applications.

Database Menus There are two main database menus, Database and Database Tools, as shown below: Database menu

Database Tools menu

Creating an Oasis montaj Database One of the fundamental technologies in Oasis montaj is its unique database architecture. This architecture is designed to let you rapidly create and import data of many kinds (ASCII and binary) into high-performance Oasis montaj databases. After data is imported into a database, you have numerous options for editing, visualizing, processing and performing other tasks. Oasis montaj features a database compression option that enables you to reduce the file size and improve the performance of Geosoft database files (*.gdb). Processing

Tutorial 2: Working with Data 49

speed is improved by compressing files because the computer takes less time to read and write to disk. Power s will especially benefit from using compressed databases. You can choose either to compress for speed, compress for size or no compression at all. Which type of compression you use is entirely up to you. It all depends on which type better suites your needs. For example, you would more than likely compress for speed if you have a lot of hard drive space available. However, if space is limited, you may wish to compress for size. T O C REATE

A

N EW D ATABASE :

1. On the Database menu, select New Database. The Create New Database dialog is

displayed. 2. Specify a New database name (tfmag.gdb). You can then specify the Maximum

lines/groups and Maximum channels/fields. The defaults are 200 and 50, which is fine for the purposes of this tutorial, but generally we recommend that you specify a number that is representative of the final estimated project size. This strategy ensures that you have enough space available in your project while not consuming excessive storage space. The size can be changed later via the Maintenance…menu option from the Data menu, should your project expand in scope. 3. Specify Compress for SPEED in the Compression box and select the [More]

button. 4. These additional options enable you to change the way Oasis montaj works with

data in the database file. These parameters control the database "page size", which is the smallest unit of memory that is read/written and stored on the database. In almost all cases, the default page size (1024 bytes) should be sufficient since this will a total database size of up to 4 Terabytes in size and will enable individual channels on a line to hold up to 64 Megabytes of data. This is sufficient for our database, for more information click the Help ( button.

)

5. Click the [OK] button. The system creates a new database with the database name

that you specified and opens a Spreadsheet window with empty Channel Header Cells and Data cells.


Database Lines/Groups Geosoft databases are organized in lines, channels and elements. The database stores all data “elements” of a particular type in individual “channels” (or columns). Database “lines” are a collection of related “channels”.

Each database “line” has a line number, version number, line type, flight number (only required for airborne data), survey date and selection status.


A “group” is a special kind of line. It also stores data in channels, but instead of using a name based on line number, version number, line type and flight number, it can be named using any alpha-numeric string (with some exceptions).

Each database “group” line has an optional “CLASS” name. Like a regular line, it has a selection status.

While all the channels in a database are accessible inside a regular line, a group line can restrict the available, displayable channels to a smaller subset, excluding those not relevant to the group’s data. A database may contain any number of lines and/or groups. If your survey data has not been collected on a line basis (i.e. is random), or cannot be organized


conveniently into groups that can be thought of as lines (such as drillhole or UXO target data), you can store all data in a single "line". Note: An additional benefit of the Geosoft database structure is that since columns are stored separately, this file format is capable of storing and manipulating data with different end point and sample intervals. Creating a New Line or Group Creating a new Line (or Group) is made easy with the the Database popup menu. 1. On the current database, select the Line (or Group) header cell, right-click and

from the popup menu, select New Line (or New Group). 2. The Create Line (or Create Group) dialog will be displayed. Enter the parameters

as required and click the [OK] button. 3. The new “Line” (or Group) will be created in your current database.


Oasis montaj ed Data Formats Oasis montaj provides seamless access to both original spatial data and processed information (grids, images and vector plots). Spatial data import formats include

Processed data import formats include

• AMIRA format files

• ArcView shape files (SHP)

• ASCII data files, CSV

• AutoCAD DXF (DXF)

• ASEG GDF files

• DATAMINE (DM)

• Blocked binary data files

• Geosoft plot (PLT)

• Database table files (single or all tables)

• Geosoft map files (MAP)

• Excel Spreadsheets

• Grid and image formats

• Flat archive data files

• MapInfo TAB files

• Geosoft binary data files

• Maxwell Plate files

• Geosoft XYZ data files

• Microstation DGN files

• ODBC data files

• Surpac (STR, DTM)

• Picodas PDAS data files

• GoCad (VO) with rotation

• RMS data files

• UBC (MOD, MSH, DEN, SUS)

• RMS DAARC 500 binary file formats

• LAS files (LAS)

• USGS data files Common Grid Formats (GRD) including

Common image formats (IMG) including

• DEM formats (GLOBE, ETOPO5, USGS)

• EOSAT MSS (Old 4 Band BIL)

• EOSAT Fast Format

• ER Mapper algorithm (ALG)

• ER Mapper grid (ERS)

• ER Mapper compressed (ECW)

• ESRI Binary Raster (FLT)

• GeoTIFF Image (TIF)

• Landmark ZMAP (DAT)

• GIF (GIF)

• Geopack (GRD)

• IMG Image (IMG)

• Geosoft grid files (GRD)

• JPEG 2000 (J2K and JP2)

• Geosoft Hypergrid (HGD)

• JPEG File Interchange Format (JPG)

• Grid eXchange Format (GXF)

• Landsat MSS (4 band BSQ) and Landsat TM

• Surfer grid file (GRD) • Texaco Startrax (GRD) • USGS (DDF, DEM) • World Geoscience (H)

• PCIDSK Format (GIX) • Portable Network Graphics Format (PNG) • Tagged Image File Format (TIFF) • Targa Image (TGA) • Uncompressed PC Paintbrush (PCX) • Windows Bitmap (BMP)


Importing Data into the Oasis montaj Database There are a number of options for importing Geosoft and third-party formatted data. In this tutorial, you will import and work with standard Geosoft XYZ files, default templates and import modes. For more information about how templates and import modes work refer to the Help system. T O I MPORT D ATA INTO A D ATABASE 1. On the Database menu, select Import and then click Geosoft XYZ. 2. The system displays the Import dialog asking if you want to “Import data into the

current database?” Select (Yes) to import the data into our previously created “tfmag.gdb” database and the Import XYZ data dialog will be displayed.

3. In the XYZ data file box, specify mag.xyz. You can click on the [Browse] button

to search for this file in your Tutorial directory. Note:

The [Browse] buttons enable you to locate and select files from anywhere on your computer or network drives. This assists in ensuring the selection of the proper files from the correct directory are chosen.

4. Click the [Template] button. The system displays the Import dialog box with the

name of the file you are importing displayed along the dialog box title bar.


5. The name of the default import template file “default.i0” is displayed in the

Template Name box. This file will include the settings specified in this dialog. If you have multiple files of the same format to import you can rename this file to be used again (e.g. ImportTFMag. i0). 6. To modify the settings for a channel, select (highlight) the channel you wish to

edit and Source Data and Output boxes to the right, specify your changes. 7. In the Source Data box you can select a Format for your numbered data. (i.e.

normal, scientific, date, time) from the drop down menu. If your data contains a value (for example –9999) that represents dummy values, enter this value in the Dummy parameter box. 8. In the Output Channel box you can select or specify a Name you want to use for

the channel in the database. You can also select the Type of numbers to use, the number of Decimal places, Width (number of digits), and the Units used for display. 9. When you are done editing and modifying your data click the [OK] button to

return to the Import XYZ data dialog box.


10. Click the [OK] button to import the data.

The imported data should look like the picture below.

Note:

The default placeholder for missing or blank data (i.e. dummy value) in an XYZ file is “*”. If the dummy value was for example, -9999, then you should enter this in the Dummy box on the template dialog box..

Drag-n-Drop XYZ Data The ability to drag XYZ files and drop them into an open database file (*.GDB) is now included in Oasis montaj. Only default parameters are used and XYZ files must be in the correct format and the database must be large enough to hold the dropped XYZ file. The ability to drag other file types directly from Windows Explorer and drop them into Oasis montaj for display is also available including; grid files (*.GRD), map files (*.MAP) and database files (*.GDB) files. Items on the Project Explorer bar may also be dragged and dropped.

Displaying Data in the Spreadsheet Unlike traditional spreadsheets, the Oasis montaj Spreadsheet windows provide a view of your database instead of the actual data in the database. This design enables


you to customize the spreadsheet to display data to your specifications. In addition, it lets you work with data in the spreadsheet without actually making changes to the data — until you decide to save the database. After you save the database, your changes are permanent. For more information about our databases, please refer to the Help system. When you import data you will notice that the system automatically displays all of your data in the Spreadsheet window. Note: When the system creates a database, it automatically creates L0:0. During the data import process, if the data that you import does not contain a line 0, so that there is no data in this line, the line is automatically deleted. If the line contains data it is retained. T O H IDE

A

C HANNEL (C OLUMN ):

1. Click once on the channel header cell labelled mag to select it. Press the [space

bar] key on the keyboard or click on the right mouse button and select Hide Column from the popup menu. The channel is hidden from the Spreadsheet view. Note: The database (*.gdb) file still contains all the data. The Spreadsheet is only used to provide a view of selected channels. T O L IST A C HANNEL : 1. Move your cursor to the top of the first empty channel header cell, right click and

from the popup menu, select List.

2. A box will appear beneath the empty channel header listing all the available

channels that currently are not being viewed in the Spreadsheet window. Select mag to display the channel in the Spreadsheet.


3. If you know the name of the data channel already, you can simply position the

cursor on a specific Channel Header Cell, type the name and click the [Enter] button. Note: If you see ‘**’, this convention indicates that the data are too wide for the spreadsheet column. To change the width of a column, place the cursor on the dividing line between the column headers. The mouse becomes a double arrow. Click on the left mouse button and drag the line to the right to increase the column width. Release the mouse button when done.

Channel Header Cells The cells immediately right of the ID Cell are called Channel Header Cells. These cells are used to identify a unique type of data contained in a column of the spreadsheet. The data for a channel appears below the channel header. The channel headers provide a visual indication of the current status of the displayed channel. If the top left corner of the header cell is marked by a black triangle, the channel is read-only, and it may not be modified. A red line at the bottom of the header cell indicates that the channel has been re-sampled in order to present a view of the data with one of the other channels on the screen.


Current X and Y (and Z) Channels Oasis montaj s "current" X and Y (and Z) channels. This capability enables s to select the channels that they would like to use as the current X and Y (and Z) channels (for example, East, North, and Relative Level). To set the current X and Y (and Z) channels, using the Coordinates|Change X, Y coordinates menu item, select the names of the new coordinate channels. This makes these channels the new current X and Y channels. You can also use this menu item to review the current settings for the X and Y channels. Markers have been added to the channel header to indicate which channels are currently defined to be the "current" X, Y (and Z) channels. The markers are little rectangles on the right side of the header cell, and contain "x", "y" (or "z") in reversed display (like the triangle protection symbol on the left). When you alter the current coordinate channels (Coordinates|Change X,Y coordinates), these markers change too. Normally, s will just get "x" and "y", but if you have a "Z" channel it will get the "z". The "z" will be used in Wholeplot databases, where DH_EAST = "x", DH_NORTH = "y" and DH_RL = "z".

Processing Data in the Spreadsheet After you open a Spreadsheet and display one or more channels, you have the option of processing the data using the Oasis montaj database tools. These tools help you apply formulas and perform database operations between channels for individual groups of points, lines or the entire database. For more information about the processing tools, please refer to the Online Help system. T O C ALCULATE B ASIC S TATISTICS

ON A

C HANNEL :

1. Click three times on the channel header cell labelled mag to highlight the mag

data in all of the selected lines (groups) in the database. The selected data is the data the system will calculate the statistics on. Note: Clicking (highlighting) the channel header once selects the header cell, clicking twice selects the channel and clicking three times selects the channel in all of the selected lines (groups) in the database. 2. On the Database Tools menu, select Report and then select Mark Statistics. The Stat Report dialog is displayed.


3. You can save a copy of the statistical report by clicking the [Save Stats] button.

The system will display the Save Stats dialog box where you can specify a name for the New statistics file then click the [OK] button to have the system save the file to your project directory.

4. On the Stat Report dialog box click the [OK] button to close the dialog box.

The following list summarizes how to obtain results on specific parts of your database: Click once on the channel header cell to highlight the header cell.

No statistics can be calculated.

Click twice (double click) on the channel header cell to highlight the data in the current line (group).

Statistics are calculated for that specific line of the database.

Click three times on the channel header cell to highlight the data in all of the selected lines (groups) in the database.

Channel statistics are calculated for all of the selected lines in the database.

Note:

The maximum value in the mag channel is 9999 - for this dataset, this number may indicate a data spike or spikes in some or all of the lines of data.


Displaying a Profile in the Spreadsheet After you open a Spreadsheet and display one or more channels, you have the option of displaying them in graphical (profile) form in a Profile window. The Profile window is composed of sub-windows called panes. You can display up to five separate panes with 32 channels of data in each pane. For more information about the Profile window, please refer to the Online Help system. T O D ISPLAY

A

P ROFILE :

1. Select (highlight) the channel header cell of the channel you wish to view in

profile format. For example, the mag channel. 2. Right-click and from the database popup menu, select Show Profile.

The profile of the channel data is displayed in the Profile Window immediately below the spreadsheet.

Note:

To see where the mag values are located with regards to the profile line, simply select a value (or a range of values) in the mag channel and the system will highlight the corresponding area on the profile (or visa versa). We recommend you experiment with the various options available for profile display, appearance, scaling and plotting etc. available via the Profile popup menu, available by right-clicking while holding the cursor over the profile window.

62 Tutorial 2: Working with Data T O D ISPLAY

THE

P ROFILE

OF

D IFFERENT L INE :

1. Move the cursor to the Line Header Cell in the top left corner of the spreadsheet.

The currently displayed line in the worksheet is L5:0. 2. Select (hightlight) the Line Header Cell, click the right mouse button and select

List from the popup menu. A list of all the line numbers in the current database will be displayed. You can think of each line number as a worksheet in the spreadsheet window. When you view a new line number a new worksheet is opened in the spreadsheet window with corresponding line number information.

3. Click on L13:0 from the list and you will see that the spreadsheet and profile

window now displays L13:0, as shown below:

4. The profile view now shows the two data spikes, which peak at a value of 9999.

These spikes were also identified in the channel statistics and should be removed from the data before performing any additional data processing. Note:

When the Line Header Cell is highlighted, you can use the [Page Up] and [Page Down] keys from your keyboard to scroll through lines. You can also use the Database Tools Bar to scroll through the lines. The figure below shows what each of these buttons do.


Database Toolbar Display First Line/Group. Click this button to show the data and profiles for the starting line in your database. Display Last Line/Group. Click this button to show the data and profiles for the final line in your database. Display Previous Line/Group. Click this button to show the data and profiles for the previous line in your database. Display Next Line/Group. Click this button to show the data and profiles for the following line in your database. Create a New Database Line/Group. Click this button to create a new line in your database. A dialg box is displayed that enables you to specify the line number, version, date, and type. If your database contains groups of data instead of lines, a new group will be created. Delete Selected Database Line/Group. Click this button to delete the currently select line from your database.

Protect and Unprotect Channels in a Spreadsheet You will notice that each channel header has a black triangle in its upper left-hand corner. This indicates that the channel is Protected and cannot be edited by the until the “Protection” is turned off. Original imported data are automatically stored as protected data. T O R EMOVE /A DD C HANNEL P ROTECTION 1. Select (highlight) the channel header cell you want to remove the protection from,

right-click and from the popup menu, deselect (uncheck) Protected. 2. The system removes the black triangle from the top left corner of the channel

header cell, indicating the channel is no longer protected. Note:

Using the database popup menu you can also select to Protect All or Protect None of the database channels. Check the Protect All option to protect all of the channels in your database and Protect None to remove the protection from all of the channels.

3. To protect the channel, select the header cell, right-click and from the popup

menu, select (check) Protected. The black triangle is returned to the top left corner of the channel header cell, indicating that the channel is protected.

Creating Working Channels in the Oasis montaj Database You can create new channels in your database to store the results of filters, mathematical expressions, or any other processing operations. We recommend that you create a new channel for storing any changes you make to the original imported


data. In this tutorial we need to create a new channel into which we can copy the original mag channel to for editing purposes. T O C REATE

A

N EW C HANNEL :

1. Move to the top of the next empty column and highlight the channel header cell

using a single click of your left mouse button. 2. Type in the name of the new channel (magedited) and press the [Enter] key on

your keyboard. The system displays the Create Channel dialog box. Note that, you can also select the channel hearder cell, left click and from the popup menu select New, to display the Create Channel dialog.

3. Click the [OK] button to accept the default values. The system creates a new

channel in the database named magedited and fills this channel with dummy values (i.e. *). 4. On the Database Tools menu, select Channel Tools|Copy channel. The Copy a

channel dialog is displayed.

Tutorial 2: Working with Data 65 5. Select mag from the dropdown list for the Copy FROM box and magedited from

the dropdown list for the TO box. 6. Click the [OK] button.

The system copies values from the mag channel into the newly created magedited channel. T O C REATE A N EW C HANNEL U SING (O PTIONAL ):

THE

M ATH F ORMULA T OOL - A LTERNATE M ETHOD

Follow steps 1 through 3 above; however use a different channel name such as magedited2. 1. Click left mouse button three times on the magedited2 channel header cell to

highlight all of the data within this channel. 2. Press the [=] key from your keyboard to activate the Math Formula Tool. You can

see the Math Formula Tool is activated by looking at the status bar of the spreadsheet window. 3. Type mag in the formula bar. Typing mag means the new channel will be equal

to the mag channel. Notice that as you type the formula, it is written in each channel cell as well as at the bottom of the screen.

4. Press the [Enter] key on your keyboard to activate the formula and have the

system display the values in the selected channel. Note: The math formula tool s simple math and algebraic functions as well as temporary variables for complex expressions using the channel names as variables. For more information, see the Help system. We will use this math tool later in the tutorial. T O D ELETE

A

C HANNEL

FROM THE

D ATABASE :

We do not require two magedited channels; therefore we can easily delete the magedited2 channel from the database. 1. Before you can delete a channel from the spreadsheet window you need to make

sure the channel is not protected (i.e. there is no black triangle in the upper left corner of the channel header cell). If you try and delete a channel that is protected the system will not allow you to proceed with the deletion process. 2. Right mouse click on the magedited2 channel header cell and select Delete

channel from the popup menu.


3. The system will display the Delete dialog box. This dialog box is a safety feature

confirming that you really wish to delete a channel from the database.

4. Click the [Yes] button to permanently delete this channel from your database

(Note that, the default is No this is a secondary safety feature preventing you from pressing the Enter key by mistake, deleting the channel). Note: It is important to realize that deleting a channel is very different than just hiding a channel from spreadsheet view. When you hide a channel from the spreadsheet it is still there in the database and can be retrieved simply by listing the channel again. When you delete a channel it is not only removed from the spreadsheet view, but it is also deleted from the database as well.

Editing a Channel in the Database Once you have made a copy of the channel you can now edit and process the data found in that channel. In this case we wish to remove the two data spikes found on line 13:0 of the tfmag.gdb database.

Tutorial 2: Working with Data 67 T O E DIT D ATA IN

A

C HANNEL U SING

THE

P ROFILE V IEW :

1. Before you can edit a channel you must make sure that channel is not protected.

Then, ensure that you are viewing the correct line 13 (L13:0) in the worksheet, and that you have chosen the magedited channel to edit. 2. With the magedited channel selected, right-click and from the poup menu, select

Show Profile. The system displays a profile of the data in the profile window below the spreadsheet. 3. Move to the profile window and click on the first data spike (there are two on the

line). You will notice that the corresponding data value to that spike, 9999, is highlighted in the spreadsheet view at sample (fiducial) 32 and a small box is drawn at the top of the data spike in the profile window. Clicking anywhere in the profile view will display the corresponding value in the spreadsheet view.

4. Click with your mouse on the 9999 value in the corresponding magedited

channel. Press the [Delete] key from the keyboard to remove the value from the database. A dummy value (*) will appear. 5. Repeat the procedure for the other data spike found at fiducial 131 and a second

dummy value (*) will appear. Your profile should now look like the one shown below.


Editing Data Using Conditional Expressions Spikes may also be removed from a dataset by using a conditional math expression. Select the magedited channel and press “=”, then using the Math Formula Tool, type the following formula:

This formula states that if the mag value is less than 9000, magedited will equal the mag value; otherwise it is set to the dummy value. This procedure works in this case because the bad data spikes are outside of the valid data range.

Using the Channel Math Expression Tool The ability to create, save, load and execute math expressions in Oasis montaj has never been easier. Three new standardized Math Expression Builder tools have been added, each of these tools provides all of the math expression keywords on a single tabbed dialog, for each data type. These easy-to-use tools enable you to build mathematical expressions for Channels (1D data), Grids (2D data), and Voxels (3D data).


The Math Expression Builder uses normal algebraic notation that is a combination of keywords, such as functions and operators that calculate values or change the values of variables (i.e. Channels, Grids or Voxel data). TO

ACCESS THE

C HANNEL M ATH E XPRESSION B UILDER

1. On the Database Tools menu, select Channel Math. The Channel Math

Expression Builder is displayed.


2. To display the available Operators and Functions click the [Operators] button

and all of the Operators and Functions that are available to help you build your math expression will be displayed. 3. For detailed information on the Math Expression Builder Components and how to

apply them, see the Help topic, Math Expression Builder (Help|Help Topics).

Interpolating Data Now that you have removed the spikes and examined the database for other possible errors, you may wish to interpolate the data through the gaps created when you removed the data spikes. T O F ILL G APS

IN A

D ATA C HANNEL U SING I NTERPOLATION :

1. On the Database Tools menu, select Channel Tools|Interpolate. The Interpolate

Dummies dialog is displayed.


2. Select magedited as the Channel to interpolate and also select magedited as the

Output interpolated channel. Select Minimum Curvature as the Interpolation method. Click the [OK] button. 3. The system will interpolate the gaps created in the data during the editing session

using the minimum curvature method of interpolation. Click the Help ( for more information on this function.

) button

4. Display the mag and magedited channels in the profile window by right clicking

on each channels header cell and selecting Show profile from the popup menu. You can now compare the edited data against the raw data.

Note:

By displaying the two profiles in the same profile window you can examine the effectiveness of interactive editing and interpolation on the original data. However, note that the profiles have different vertical scales magedited is (4720.90 – 5974.10) and mag is (4639.92 – 10104.08).


Profile - Y Axis Options The Y Axis Options enables you to set scale options for the Y axis of the profiles in the profile window. TO

DISPLAY THE TWO PROFILES AT THE SAME SCALE :

1. In the Profile window, right-click and from the popup menu, select Y Axis

Options.The Y-Axis Scale Options dialog will be displayed.

2. Under Changing Lines selection, select Scale to fit for each line and under the

Profile Scaling section, select Same axis scale for all profiles. 3. Click the [OK] button to display the two profiles at the same scale.


The following list summarizes the different scale options available to you: Changing Lines Scale to fit for each line

Adjusts the scale in the profile box to fit each line that is displayed.

Same axis scale for all lines

Uses the same axis scale for all the profiles that are displayed.

Same dynamic range, centered for each line

Uses the same dynamic range, centered for each line that is displayed.

Profile Scaling Scale each profile separately

All profiles (including those from different channels) are set to a different scale.

Same axis scale for all profiles

All profiles (including those from different channels) are set to the same scale.

Same dynamic range, centered for each profile

Uses the same dynamic range, centered for each displayed profile.

Profile – X Axis options The X Axis Options enables dialog enables you to select the channel to use as the Xaxis and automatically rescale the X-axis as well as display Vertical grid lines. T O S ELECT X A XIS C HANNEL : 1. In the Profile window, right-click and from the popup menu, select X Axis

Options.The All- Options dialog is displayed.

2. Use this dialog to select the X-Axis to use in the profile window, to select to

automatically rescale the X-Axis, to display vertical grid line and at what interval.

74 Tutorial 2: Working with Data 3. Click the [OK] button to continue and your profile will be updated.

Profile Options Use the tabbed Profile dialog to specify the options for the current profile. This diacludes five tabs: Data Info, Line Styles, Colours, Symbols, and Grid. For more information on the Profile dialog and the individual tabs, click the [Help] button on the tab of interest.

Master Sample The Master Sample channel is used to force all other database channels to be sampled at the same fiducial rate as the selected channel. The Master Sample channel is identified by blue line under the channel header. This feature is useful when you want to edit data from a channel that has a larger fiducial rate (data sampled less often) then other channels in the database. By default, the spreadsheet window displays data using the channel with the smallest fiducial (most frequent sampling) rate. For example, consider a database with two channels. Channel 1 has a fiducial sampling rate of 10 readings/second. This channel is considered to be smaller (more frequent) than Channel 2, which was sampled at 1 reading/second. By making Channel 2 the Master Sample channel, Channel 1 is displayed at the same rate so that only every tenth fiducial is displayed.

Tutorial 2: Working with Data 75 T O A CTIVATE

THE

M ASTER S AMPLE :

1. Right click on a database channel header and select "Master Sample" from the

popup menu. 2. A blue line will be displayed under the channel header. TO

REMOVE THE

M ASTER S AMPLE :

1. Right click on a database channel header and select "No Master Sample" from the

popup menu. 2. The blue line will be removed from under the channel header.

Saving Changes to Databases When you are ready, you may want to make your changes permanent in the database. T O S AVE C HANGES

TO

Y OUR D ATABASE :

1. On the Database menu, select Save Database Changes. 2. The system displays the Save Changes dialog box. Click the [Yes] button to

confirm the save.

3. The system updates your database and the changes are now permanent. Note:

To undo changes, click the Discard Database Changes menu option from the Database menu. This will restore your database to its last saved state.

Tutorial 3: Importing and Exporting Databases 77

Tutorial 3: Importing and Exporting Databases Oasis montaj provides a variety of importing and exporting capabilities, including: • Reading directly from common databases (Access, FoxPro, Dbase, Paradox and OBDC) • Importing ASCII data interactively via Excel-style import wizard • Exporting your data as Microsoft Access database format (*.mdb) • Exporting ASCII data The following menus show you the importing and exporting options available to you in the system. Database|Import menu

Database|Export menu

Before You Begin this Tutorial: Oasis montaj uses ADO and ODBC software developed by Microsoft to connect to other spreadsheet and database applications. In this tutorial, we will guide you through these tasks. The tutorial is structured using the following steps:

78 Tutorial 3: Importing and Exporting Databases

• • • •

First we will export some data from an Oasis montaj database to a Microsoft Access database to familiarize you with the exporting process. We will then proceed to import the Access database into a new Oasis montaj database to familiarize you with the import process. You will then create your own ASCII data set by exporting from Oasis montaj. Lastly you will import this Ascii data back into a new Oasis montaj database.

Getting Ready to Export to a Microsoft Access This tutorial will use the tfmag.gdb database file. This data file contains x and y ground locations as well as data (mag) values. Although the data is magnetic data, it is suitable for demonstrating the standard manipulations you will perform with any type of data with which you are working. Data is arranged in lines (i.e. multiple worksheets) which is not typical for certain types of data (i.e. random geochemical data) but again, you should be able to generalize this to the case in which you have only one line (i.e. random data).

Exporting to Microsoft Access Database Format Before working with the database export capabilities, please be aware that Geosoft currently s table export only to Microsoft Access databases. Typically this should not hinder you in practice since Access is widely ed by other database applications. However, we apologize for any inconvenience this limitation may cause. If you have any questions or concerns, please do not hesitate to any of our Technical groups around the world. The system offers you several choices for creating an Access database, namely exporting to: Individual tables

Each line (or group in the case of drillhole data) has its own table in the output database.

Single table

All lines are stored in one table in the output database.

Note:

As a rule of thumb, if you are working with multiple lines, we recommend that you export lines as Individual tables so that you can keep track of them in the future. If you are working with a single line (i.e. geochemical data), it is more likely that you will export the line as a Single table. In the following procedure, we will export data as Individual tables within a database.

T O E XPORT

TO A

M ICROSOFT A CCESS D ATABASE :

1. Make sure the tfmag.gdb database is open in your project. 2. On the Database menu, select Export and then select Microsoft Access. The

system displays the Save to Microsoft Access database (MDB) dialog.


Note:

If you choose Selected lines as the Lines/Groups to save option, you can make sure the lines you wish to export are selected according to your specifications. To do this, you can can choose certain lines to select via the Line Selection Tool, which can be accessed from the line header cell popup menu and selecting, Selections|Selection Tool (as shown below).

3. Specify an Output MDB file name (Export_Access) and the rest of the options as

shown above. Click the [OK] button. 4. The system displays a progress dialog box as it creates the new Access database.

Importing a Database Table Now that you have created a Microsoft Access database we can show you how to import an Access Database. Normally you would already have created your database by actually using Access, but for purposes of this tutorial we had to create a (*.mdb) file first to be able to show you how to import one later. Geosoft’s database table import assumes that the database is a Microsoft Access database (*.mdb). If it is not, the system prompts you for a database type (any of the following): dBase III dBase IV dBase 5

FoxPro 2.0 FoxPro 2.5 FoxPro 2.6

Paradox 3.x Paradox 4.x Paradox 5.x

80 Tutorial 3: Importing and Exporting Databases T O I MPORT

A

D ATABASE T ABLE :


displayed. Specify a New database name (Import_Access) and click the [OK] button to open a new empty database. 2. On the Database menu, select Import| Database Table and then click All Tables.

We chose the All Tables option of importing because when we originally exported this data we exported it as individual tables. Therefore, we would like to import all the tables back into the database. If we choose the Single Table option we could choose individual lines and fields we wished to import. 3. The system displays the Import Database dialog. Since you just finished creating a database to import the data into, click the [Yes] button. Note:

4. The system displays the Import Entire External Database dialog.

5. Use the [Browse] button to select Export_Access.mdb as the File to import.

Specify Lines from the Store tables as drop down menu. Click the [OK] button. The system imports file into the database.

Exporting to an Excel Comma Separated Value (CSV) File An important capability is the ability to export to Excel-style comma separated value (*.CSV) ASCII files. This timesaving feature enables you to quickly export your processed data from Oasis montaj and perform specialized analysis or processing in Excel as required. T O E XPORT

TO AN

E XCEL F ILE :

1. Make sure the tfmag.gdb database is open in your project. 2. On the Database menu, select Export and then select the CSV etc. The Export to

Other format dialog is displayed.


3. Specify the Format as CSV (Excel) and the output Data file Name as

Export_Excel. Click the [OK] button. The system exports the data to the designated file.

Importing an Excel Comma Separated Value (CSV) File Oasis montaj provides a variety of options for easily importing Excel data. In this tutorial, we demonstrate the use of Geosoft’s Import Wizard technology. T O I MPORT E XCEL F ILES : 1. On the Database menu, select New Database. The Create New Database dialog is

displayed. Specify a New database name as (Import_Excel) and click the [OK] button to have the system create the new empty database. 2. On the Database menu, select Import|Ascii. The Import Wizard dialog is

displayed.

3. Use the Browse (

) button to select the File to import as (Export_Excel.csv), click the [Wizard] button to begin the ASCII import wizard.

4. The system scans the file and displays the first of three Data Import Wizard

dialog boxes. The wizard displays a preview of the data file and automatically determines the File Type containing the data (i.e. Delimited — separated by commas).


5. In the four fields in the middle of the dialog box specify which line in the file

contains the data headings (i.e. channel names), data units (“m” or “ft” ect.), which line to begin importing data on and the number of lines to display in the preview rows. 6. If your import data had several columns of data you can use the horizontal scroll

bar at the bottom of the display window to view the columns. Click the [Next>] button to continue. 7. The second dialog box in the Data Import Wizard is displayed. Specify the

Column delimiters as Microsoft Excel CSV for the type of character used to separate the column text. In this case, the system displays the data in columns by drawing lines in the preview window indicating the way in which it is preparing to import your data. Click the [Next>] button to continue.


The Data Import Wizard enables you to easily import data from any Ascii spreadsheet or data file. The Data Import Wizard s both Delimited and Fixed Field Ascii files. The Data Import Wizard also imports Microsoft Excel Comma Separated Value (CSV), Comma Delimited, White Space Delimited and Tab Delimited data files. The window at the bottom of the dialog box shows the file that is being imported. For more information about the Data Import Wizard settings, read the Ascii Import Wizard help topic or click the Help ( ) button on the dialog box 8. The system displays the third dialog box in the Data Import Wizard. The wizard has scanned your data and determined the Channel Type of data with which you are working (Data in this case). It is always good practice to review your data to ensure that the wizard has selected the correct columns. The Parameters area in the dialog box shows the name, label, type and format of data of the column highlighted in the preview window. Note: In the dialog box below, we have selected the Y column to show how the corresponding parameters are displayed in the Parameters box.


9. Click the [Finish] button. The system displays the Save the template? Dialog.

10. Click [Yes] to save the import template. For more information on the import

template click the Help ( displayed.

) button.The Save the template dialog box is

11. In the Template box you can either accept the default name for the import

template or rename the template. For our purpose we will accept the default name and click the [OK] button. The Import dialog box is displayed.


12. Click [Yes] to import data into the current database.The Import Wizard imports

the data to the Import_Excel.gdb as shown below.

Drag-n-Drop Geosoft Database Files The ability to drag database files (*.GDB) from Windows Explorer and drop them into an open project is now included in Oasis montaj. The ability to drag other file types directly from Windows Explorer and drop them into Oasis montaj for display is also available including; grid files (*.GRD), map files (*.MAP) and s can also drag XYZ files and drop them into an open database file (*.GDB). Items on the Project Explorer bar may also be dragged and dropped.

86 Tutorial 4: Basic Mapping and Gridding

Tutorial 4: Basic Mapping and Gridding Maps provide a key tool for interpretation for many earth science applications. Oasis montaj provides a wide range of capabilities for performing both basic and advanced mapping. In addition, the map is an important part of the dynamic linking and imaging capabilities in Oasis montaj. In this tutorial, we guide you through basic map creation. The general steps to follow when creating a map include: •

Selecting data for mapping

•

Creating a new map

•

Setting up map layout templates

•

Creating a base map

•

Plotting survey lines

•

Plotting profiles

•

Moving around the Map

•

Gridding data

•

Plotting contours

Later tutorials focus on custom map creation, dynamic linking and imaging, and adding special elements such as symbols to maps.

Tutorial 4: Basic Mapping and Gridding 87

Map Menus There are two main map menus, Map and Map Tools, as shown below: Map menu

Map Tools menu

Selecting Data for Mapping and Processing Oasis montaj creates base maps and map elements, and performs other processing (such as gridding) based on the lines (or groups in the case of drillhole data) selected in the database. By default, when you import data, all lines are selected. For the purpose of this tutorial, we recommend that you leave all lines selected. After you run through the tutorial initially, you may want to experiment with turning lines on and off and re-creating your map. T O S ELECT D ATA FOR P ROCESSING : 1. First ensure that the tfmag.gdb database is open and selected in your current

project.

88 Tutorial 4: Basic Mapping and Gridding 2. Select (highlight) the line header cell, right-click and from the popup menu select,

Selections and then select Selection Tool. 3. The Line Selection Tool dialog is displayed.

• • • •

You can highlight the lines you want to select or deselect individually or click the [Highlight lines by range] button to select lines by range. Clicking the [Select highlight] button or [Deselect highlight] button will either add a check mark beside the highlighted lines or remove a checkmark. Lines that are selected will have a check mark beside them and lines that are not selected will have no check mark beside them. If the line is not selected, it will not be included in the maps you create or data you process. For this tutorial make sure all the lines are selected. Click the [OK] button.

Creating a New Map Oasis montaj introduces an intelligent entity called a Map. Physically a map is a special graphic file (*.MAP) containing drawings and images. In practice, however, a map is smarter than a basic file because it enables you to edit interactively, apply dynamic linking and track the map creation processes. When you create or open a map in Oasis montaj, the system displays a Map window in the project. For a new map, the window is initially empty. For an existing map, all map elements are displayed when the window opens. An important component of the map is the map template. Templates control placement of base map elements (surrounds), contours, grids, plots, images and any other graphics elements required to complete your map. You will learn more about templates in a following exercise. For more information on mapping, map components and working with maps, click the Help ( interest. T O C REATE

A

) button on the dialog of

N EW M AP :

1. Select the tfmag.gdb database in your current project.

Tutorial 4: Basic Mapping and Gridding 89 2. On the Map Tools menu, select New Map and then select New Map from X,Y.

The Data range to map dialog is displayed.

The Data range to map dialog is used to create a new blank map to fit the data range specified. The data range can be entered manually, or it can be determined from the range of the selected data in the current database, from the range of a grid file, or interactively by defining an area on a map. 3. Click the [Scan data] button to have the system query the database for the Minimum X, Y and Maximum X, Y coordinates and the Distance units. Note: If the scanned data or grid file does not have an established unit, "metres" is assumed. It is important that the distance units accurately reflect the units of the data range. This default value can be modified in the Edit|Settings|General dialog. 4. Click the [Next] button. The Create a new map dialog is displayed.

Note:

5. Enter a Map name (tfmag.map), Map template (portrait letter) and then click

the [Scale] button. The system automatically calculates a scale that will fit the data on the map template. Just it’s recommended to round the scale to a more efficient number, for example (100000). 6. Click the [Finish] button display the new blank map. Note:

If no scale is specified, a scale will be chosen which will fit all of the data within the chosen map sheet.


Creating a Map Template using Interactive Tools The Interactive Map Template Creation Tool simplifies map making by providing the ability to use standard map templates from our template library or interactively create customized map templates for use within Oasis montaj. The template can be used to create simple base maps for standard presentations or very sophisticated final maps. This XML based template s the creation of multiple data views on a single map. The may define titles, text, logos, colour bars, and may even include background graphics or images in each view. For the power s, the templates are fully scriptable.

Working with Interactive Map Template Tool The Interactive Map Template Creation Tool is designed to simplify map making by providing easy-to-use interactive tools for modifying or creating customized map templates for use within Oasis montaj. “Data linking”, which can be used very effectively to organize the layout on an output map (especially "map" style maps where the base view has a fitting view defined) is also available.


Adding a map template to your current project can be achieved in two ways: • On the Map Tools menu, select Map Template and then select one of two options, New Blank Map Template or New Template FromLibrary. • On the Map Template Tools Bar, select one of the following buttons; New Template fromLlibrary ( (

), New Blank Template (

) or Open Map Template

).

Once you have a map template created and/or opened in your current project you can quickly and easily add new base group to your map template using the Add new base group button ( ) on the Map Template Tools Bar or by selecting the view you want to add the group to on the map template window, right-click and from the popup menu, select Add new base group. When adding new Data Views to your map template, you can define the data extents and projection information or leave the area undefined. Data groups can be added ) on the Map Template using the Add new data group to current view button ( Tools Bar or by selecting the view you want to add the group to, in the map template window, right-click and from the popup menu, select Add new data group to current view. For more information on working with the New Map Template Interactive Tools, see the Oasis montaj online Help Topics. To quickly locate help for the New Interactive Map Template Tools, specify “Interactive Map Template Tool” on the Search tab.

Automated Map Sheets The new Automated Map Sheets option creates a number of tiled maps given a map template and a master map (the master map will contain the entire area that will be divided into individual map sheets). Along with the interactive map template creation tool, s can interactively create customized map templates for use within Oasis montaj. These XML based templates the creation of multiple data views on a single map. For more information on using the new Automated Map Sheets option, see the Automated Map Sheets Technical Note, available online at www.geosoft.com/resources/technotes/

Creating MAPPLOT Map Templates (manual) The system provides a variety of default templates that enable you to create your own standard maps with logos, custom layouts and other elements as required. For example, you may use the default A4 or A3 templates to create your own layout that you use regularly for making a map. Note: When you create a map template, it is saved permanently in your system. When you are learning the system, we suggest you experiment using the same


template until you are ready to create a final version with a custom name. You may want to make up a testing template, called TEST, for example. T O C REATE Y OUR O WN MAPPLOT M AP T EMPLATE : 1. On the Map Tools menu, click New map and then click New map from X,Y. 2. The Data range to map dialog is displayed. Click the [Scan data] button to have

the system query the database for the data ranges and report the Minimum X,Y and Maximum X,Y coordinates. Click the [Next>] button. 3. The Create a New Map dialog is displayed. Enter a Map name (New

Template.map) and choose portrait A4 as the Map template. 4. Click the [Templates] button. The MAPPLOT Template Manager dialog is

displayed.

5. Click the [New] button to create a new template, so that the original template is

not overwriten. The New MAPPLOT Template dialog is displayed.

6. Use this dialog to specify a New template name (e.g. NEW_A4) and click the

[OK] button. The Edit MAPPLOT Template dialog is displayed.


7. Change the Map style to (figure). Figure style maps have a layout with the title,

scale bar and north arrow located at the bottom of the map whereas map style maps have a layout with the title box, scale bar and north arrow along the right hand side of the map. You can leave the rest of the default values as they are. 8. Click the [OK] button to continue. The system will return you to the MAPPLOT

Template Manager dialog. Click the [OK] button. 9. The Create a new map dialog box is redisplayed with (NEW_A4) as the specified

Map template.

10. Click the [Scale] button. The system automatically chooses a scale that will fit the

data on the map template. Just to round the scale to a more efficient number (150000).

94 Tutorial 4: Basic Mapping and Gridding 11. Click the [Finish] button to create and open the empty map in your current

project.

Creating a Base Map You can customize your base map with many elements, including map surround, north arrow, scale bar, reference grids, latitude/longitude annotations, text blocks/ballons and titles. The layout of your base map can either be map or figure style. Figure style maps have a layout with the title, scale bar and north arrow located at the bottom of the map whereas map style maps have a layout with the title box, scale bar and north arrow along the right hand side of the map. The following pictures show the difference in layout between the two styles.

T O C REATE

AND

P LOT

A

F IGURE S TYLE B ASE M AP :

1. Make sure your blank tfmag.map file is open and selected in the project. 2. On the Map Tools menu, select Base Map and then select Draw Base Map. The

Basemap layout dialog is displayed.


3. This dialog box is the first dialog box in the base map layout wizard. The type of

Map style that you choose here will reflect the type of dialog boxes to follow. Choose figure as the Map style and specify a Map scale of 100000. The rest of the default values are fine the way they are. Click the [Next>] button to continue.

96 Tutorial 4: Basic Mapping and Gridding 4. The system displays the Figure style base map dialog box. You can specify

different types of display styles for the Reference grid via the drop down menu. Choose dotted lines for the Reference Grid box. Click the [Next>] button to continue.

5. The system displays the Figure titles dialog box. Specify a Title (Figure Map

Style) and a Sub-Title(s) if you wish. Click the [Finish] to plot the basemap in your current open tfmag.map. Your map should look similar to the one shown below.

Tutorial 4: Basic Mapping and Gridding 97 T O C REATE

AND

P LOT

A

M AP S TYLE B ASE M AP :

1. Create a new blank map using the landscape A4 Map Template. You will need to

modify this template to change the map style from figure to map. Call this map New Map_Map Style. Click the [Finish] button, your new blank map should be open and selected in the project. 2. On the Map Tools menu, select Base map and then Draw base map. The Base

map layout dialog is displayed.

3. This dialog box is the first dialog box in the base map layout wizard. The type of

Map style that you choose here will reflect the type of dialog boxes to follow. Choose map as the Map style and specify the Map Margins as shown above.

98 Tutorial 4: Basic Mapping and Gridding 4. Click the [Next>] button to continue. The s Full map style base map dialog is

displayed.

5. You can specify different types of display styles for the Reference grid via the

dropdown menu. Choose dotted lines for this tutorial. 6. Click the [Next>] button and the Map title block dialog is displayed.

7. You can specify the map titles and sub-titles as shown above and then click the

[Finish] button to plot the basemap on the current open map.

Tutorial 4: Basic Mapping and Gridding 99 8. Your map should look similar to the one shown below.

Plotting Survey Lines For line-oriented Geoscience surveys, you may want to display survey lines (flight lines for airborne surveys. T O P LOT S URVEY L INES : 1. Select (highlight) the New Map_Map Style.map. 2. On the Map Tools menu, select Line Path.

100 Tutorial 4: Basic Mapping and Gridding 3. The Line path plot dialog is displayed. You can leave the defaults as they are.

4. Click the [OK] button and the system displays the survey lines on your New

Map_Map Style.map map.

Plotting Profiles For line-oriented Geoscience surveys, you can also display plan view profiles of the data values for each survey line. T O P LOT P ROFILES : 1. Make sure New Map_Map Style.map is selected in your project.

Tutorial 4: Basic Mapping and Gridding 101 2. On the Map Tools menu, click Profile. The Profile plot dialog is displayed.

3. Choose the profile channel (magedited). Set the profile scale (units/mm) as 50

and the profile base as 5000. Change the line colour to red and click the [OK] button.

102 Tutorial 4: Basic Mapping and Gridding 4. The system displays the plan profiles of the channel selected on your map. Click

the Help ( ) button for more information regarding the parameter selections available in the Profile plot dialog box.

Moving Around the Map Once you have your map displayed, you may want to zoom into the map so that more detail is displayed. You may also wish to move around the map using other options. The following is a list of some of the different types of viewing options available, on the Map Layout Bar, for moving around and viewing the map with ease: Zoom Box

Click this button to activate the Zoom Box. Click on the map, then while holding down the left mouse button, move your cursor to box in the area of the map you want to zoom, click the left mouse button to select the area. Click the mouse button again to zoom to the area selected. Note: Once the box has been defined, the cursor and the box are linked and by moving the cursor around the map you can move the box to another location, and then click the left mouse button to zoom to the boxed area. You can also access this command by clicking the right mouse button on a map and selecting Zoom Box from the popup menu.

Pan

Click this button to Pan around in the currently selected map. Click the left mouse button and while holding the button down, move the hand cursor to pan around the current map area.

Tutorial 4: Basic Mapping and Gridding 103 You can also access this command by clicking the right mouse button on a map and selecting Pan from the popup menu. Interactive Zoom

Click this button to activate the interactive zoom. Click on the area of the map you want to zoom (e.g. an anomalous location on a grid), then while holding down the left mouse button, move your cursor left to zoom out and right to zoom in on the selected area. You can also access this command by clicking the right mouse button on a map and selecting Interactive Zoom from the popup menu. Click this button to zoom in and increase the displayed map features by 50%.

Zoom In

You can also access this command by clicking the right mouse button on a map and selecting Zoom In from the popup menu. Click this button to zoom out and shrink the displayed map features by 50%.

Zoom Out

You can also access this command by clicking the right mouse button on a map and selecting Zoom Out from the popup menu. Click this button to display the whole map area in the map window.

Full Map

You can also access this command by clicking the right mouse button on a map and selecting Full Map from the popup menu. Zoom to Selection

Click this button to zoom to the selected map view or group. You can also access this command by clicking the right mouse button on a map and selecting Zoom to Selection from the popup menu.

Previous Extent

Click this button to undo all changes that you have made since the last time you saved the map. This command is useful for removing text and graphics that you may have added accidentally. When working on a map, you may prefer to use this command periodically so that you undo only a few changes at a time rather than your entire set of map edits and other changes. You can also access this command by clicking the right mouse button on a map and selecting Last View from the popup menu.

Next Extent

Click this button to redo the latest changes that you have made since the last time you saved the map. This command is useful for adding text and graphics that you may have removed accidentally.

For more information, see the May Layout Bar help topic (Help|Help Topics). T O U SE

THE

Z OOM B OX O PTION :

1. Click the Zoom Box button (

) on the Map Layout Bar, or right click on the map and select Zoom from the popup list.

2. Your cursor will turn into a crosshair. Define a box by clicking the top left and

bottom right corners of the area of interest. Then click once to execute the zoom command.


. 3. The system zooms into the defined area.

T O U SE

THE

P AN O PTION :

1. On the Map Layout Bar, click (

the popup menu.

) or right click on the map and select Pan from


2. Your cursor will turn into a hand

. Holding the left mouse button down, use

the mouse to pan around the map. T O U SE T HE Z OOM I N O PTION : 1. On the Map Layout Bar, click (

) or right click on the map and select from

Zoom In from the popup menu. 2. The map will be reduced by 50% in the map window. T O U SE

THE

F ULL M AP O PTION :


) or right click on the map and select Zoom to

Full Map from the popup menu. 2. The map will be displayed in full view in the map window. T O U SE

THE

L AST V IEW O PTION :


) or right click and select Last View from the

popup menu. 2. The map will be displayed as it was last displayed before a new view was shown. M AP T OOLS B AR T O U SE

THE

R EDRAW O PTION :

1. If you manually resize the map window or perform editing on the map you may

need to redraw the map to refresh its current view. On the Map Tools Bar, click ( ) or right click and select Redraw from the popup menu. 2. The map will be redrawn and redisplayed in the map window.

The last three buttons on the toolbar determine on which maps the zooming will occur: [This Map Only] button will zoom only the current map, which will be highlighted. • [All Maps] button will zoom all the maps, which share the same coordinate system. • [Other Maps Only] button will zoom all the other maps, which share the same coordinate system, with the exception of the current map. This allows the use of one map as a reference. To find out the function of the other buttons on the Map Tools Bar, hold the cursor over the button until a description appears. For more information on the tools on the Map Tools Bar and any other toolbar, see the online Help. •

106 Tutorial 4: Basic Mapping and Gridding Map Views - Popup menu (Hotkeys displayed on the right)

Map Groups – Popup Menu (Hotkeys displayed on the right)


Map Window Status Bar The projection information in the status bar is cleared when there are no active maps. Projection information from the active map view is displayed in the status bar, when the map is no longer active, which could lead to the projection being incorrectly interpreted as associated with other datasets such as the active Geosoft Database (*.GDB). Now the projection is cleared unless the map is activated. Configurable Hotkeys Oasis montaj now provides configurable Hotkeys enabling quick and easy access to menu items including all map tools. The GX|Database Settings|Configure GDB Shortcut Keys menu item provides an interactive dialog enabling you to set your own hotkeys or view the defaults.


Gridding Data Gridding refers to the process of interpolating data onto an equally spaced “grid” of values in a specified coordinate system, such as X-Y. In this system, the following gridding methods are available: •

Bi-Directional Overview (page 108)

•

Minimum curvature Overview (page 109)

•

Kriging Overview (page 110)

•

Tinning Overview (page 112)

•

Trend Enforcment Gridding Overview (page 112)

•

Gridding using the Bi-directional gridding method (page 112)

Grid and Image Menu There is a main menu for grids and images, Grid and Image as shown below: Grid and Image Menu

The Grid and Image menu includes options for creating, processing, displaying, analyzing, and converting grids and images. Bi-Directional Bi-Directional is a numerical technique for parallel survey lines, lines with some tie lines or roughly parallel lines. Use BIGRID, if the data is collected along lines that are roughly parallel, as in the following examples:


Parallel Lines

Lines with some tie lines

Roughly parallel lines

BIGRID is not able to use the tie lines, as shown in the middle example, because of the way the gridding algorithm works. If the data on the tie lines is important, RANGRID or KRIGRID should be used. The Bi-directional gridding method (BIGRID GX), is ideal for line oriented data because it inherently tends to strengthen trends perpendicular to the direction of the survey lines. In this way, BIGRID can take advantage of the fundamental characteristics of line-based surveys.

Note:

The gridding process is carried out in two principle steps. First, each line is interpolated along the original survey line to yield data values at the intersection of each required grid line with the observed line. The intersected points from each line are then interpolated in the across-line grid direction to produce a value at each required grid point. Geological trends in the data can be emphasized by the appropriate orientation of the grid so that the second interpolation is in the direction of strike. In addition to trend enhancement, BIGRID allows the method of interpolation to be selected independently for the down-line and across-line directions. The interpolations available are linear, cubic spline (minimum curvature) or Akima spline. Filtering of the line data before interpolation is also possible. BIGRID can design and apply non-linear and/or linear numerical filters to the original line data. The use of the non-linear filter is a very effective way to remove data spikes (undesired highamplitude short-wavelength features) from the original data. BIGRID has the following features: • Unlimited number of data points per survey line • Unlimited number of survey lines • Unlimited output grid size Note: The actual maximum size of the dataset or grid that you can use depends upon the available free disk space of your computer. Minimum curvature The random gridding method (RANGRID GX ) fits a minimum curvature surface to the data points using a method similar to that described by Swain (1976) and Briggs (1974). A minimum curvature surface is the smoothest possible surface that will fit the given data values.


RANGRID first estimates grid values at the nodes of a coarse grid (usually 8 times the final grid cell size). This estimate is based upon the inverse distance average of the actual data within a specified search radius. If there is no data within that radius, the average of all data points in the grid is used. An iterative method is then employed to adjust the grid to fit the actual data points nearest the coarse grid nodes. After an acceptable fit is achieved, the coarse cell size is divided by 2. The same process is then repeated using the coarse grid as the starting surface. This is iteratively repeated until the minimum curvature surface is fit at the final grid cell size. A very important parameter in the RANGRID process is the number of iterations used to fit the surface at each step. The greater the number of iterations, the closer the final surface will be to a true minimum curvature surface. However, the processing time is proportional to the number of iterations. RANGRID stops iterating when: • It reaches a specified maximum number of iterations, or • A certain percentage of the observed points are within a limiting tolerance of the surface By default these limits are 100 iterations and 99% of points within 1% of the data range.. The RANGRID GX also has the following capabilities: • Accessing unlimited number of input observation points. • Adjustable internal tension. • Applying de-aliasing filter. • Applying linear and logarithmic gridding. • Applying projections. • Blanking un-sampled areas. • Outputing grids up to any size. Note: The actual maximum size of the grid that you can use depends upon the available free disk space of your computer. Kriging Kriging is a statistical gridding technique for random data, non-parallel line data or orthogonal line data. Use RANGRID or KRIGRID when the XYZ data is not sampled along lines that run in roughly the same direction. Such data are often called random, because they give a random appearance when the data locations are plotted. Also, line data with survey lines that are orthogonal (or have random directions) should be gridded with RANGRID or KRIGRID.


The following figure illustrates these types of data: +

+ +++ +

+

+ +

Random Data

Non-parallel Line Data

Orthogonal Line Data

If the data is relatively smooth between sample points or survey lines, then RANGRID should be used. However, use KRIGRID, if the data • is variable between sample locations, • is known to be statistical in nature (such as geochemical data), • is poorly sampled, or • is clustered. The statistical gridding method (KRIGRID GX) uses the method of Kriging to determine a value at each grid node based on the XYZ data. KRIGRID first calculates a variogram of the data, which shows the correlation of the data as a function of distance. Simply speaking, the further data points become, the less correlation we expect between points. A variogram shows this phenomena for a given dataset, and based on the variogram, you are able to select a model that best defines the variance of the data. The technique of Kriging uses this model to estimate the data values at the nodes of the grid. A significant by-product of Kriging is the ability to estimate the error of the data at each grid node. Geosoft s ordinary Kriging as well as universal Kriging. Universal Kriging differs from ordinary Kriging in that it allows the data to contain a regional trend. For a more in-depth understanding of geostatistical analysis and Kriging, refer to Mining Geostatistics written by A.G. Journel and C.J. Huijbregts, 1978. KRIGRID has the following capabilities: • Applies de-aliasing filter. • Applies linear and logarithmic gridding options. • Blanks un-sampled areas. • Calculates a variogram from the input data channel. • Output grids up to any size. • Processes unlimited number of input observation points.


s linear, power, spherical, Gaussian, exponential and defined models. Note: The actual maximum size of the grid that you can use depends upon the available free disk space of your computer. •

Tinning The ability to create a TIN (Triangular Irregular Network), and to use this TIN file to grid data using the Nearest Neighbour , Linear or Natural Neighbour methods has been added to the Oasis montaj environment. The TIN is created from a set of spatial data using the public domain Sweepline algorithm implemented by Steven Fortune of Bell Laboratories (Fortune, S 1987). The TINDB GX applies the Sweepline algorithm to the X, Y (Z-optional) data values in a Geosoft database (*.gdb) to create a binary TIN (*.tin) file. When Z values are included in the (*.tin) file, a TIN grid can be created using the TINGRID GX. The TINGRID GX applies the Nearest Neighbour, Linear or Natural Neighbour (Sambridge, Brown & McQueen 1995) algorithm to the Z values in the (*.tin) file to create a grid. The TIN gridding method requires one data point for each (X, Y) data location in the database. Tinning provides the ability to sum or average duplicate samples − data that have multiple Z values at single point locations. (Note that, when Z values are included in the (*.tin) file, only data point locations with non-dummy Z values are included.) Geosoft Tinning provides a number of ways of visualizing the TIN, including the ability to plot the TIN Nodes, the TIN Mesh (or Delaunay triangulation), the Convex Hull, and the Voronoi cells of your data. Trend Enforcement Gridding A traditional problem in gridding geophysical data, is the aliasing problem that occurs due to the presence of more samples “along the lines” than across lines. This problem leads to obvious effects including ellipsoids or ellipsoidal “beads” between lines in gridded data. There are various solutions to these types of effects including filtering and gridding along trend directions. However, these techniques may reduce geologic signal or obscure local trends. Oasis montaj “Trend Enforcement algorithm” is designed to provide a solution that preserves the character of local trends while eliminating aliasing effects. To learn how to perform trend enforcement gridding in Oasis montaj, refer to Tutorial 16: Trend Enforcement Gridding page 269. G RIDDING

USING THE

B I - DIRECTIONAL

GRIDDING METHOD

In this example, we will use Bi-directional gridding (since the data are oriented in parallel lines and we expect to have cross-line trending). You can apply Bidirectional gridding by using the Bi-Directional Line Gridding menu option or running a Control File that contains the gridding commands and parameters. The


procedures for both methods are provided. However, you will only need to follow one of the methods to perform the Bi-directional gridding successfully. If you are a new , we recommend choosing the first method. T O A PPLY B I -D IRECTIONAL G RIDDING

TO

XYZ D ATA:

1. Select the tfmag.gdb database. 2. On the Grid and Image menu, select Gridding|Bi-Directional Line Gridding. The

Bi-directional gridding of line data dialog is displayed.

3. From the Channel to grid dropdown list, select (magedited) and specify the

Output grid name as (tfmag). Note that, the file extension *.grd will be added by the system. 4. The Grid cell size should be 1/4 to 1/8 of the line separation distance. The line

separation for our data is 200 metres; therefore, we will use a grid cell size of (50). Note: The cell size is the distance between grid points in the X and Y directions. In most situations the cell size can be selected as 1/4 to 1/8 of the line separation, or the minimum station interval, whichever is greater. By default, BIGRID will choose a cell size based upon these criteria, although we do recommend that you choose the cell size directly.

114 Tutorial 4: Basic Mapping and Gridding 5. Click the [Advanced>] button to continue.

The Advanced Gridding options dialog is displayed.

6. We can leave these parameters to the system calculated intelligent defaults, for

detailed information on the Bi-directional gridding parameters, click the Help ( ) button. 7. Click the [Finish] button and the data will be gridded and displayed in your

current project. T O A PPLY B I -D IRECTIONAL G RIDDING

TO

XYZ D ATA U SING

A

C ONTROL F ILE :

1. On the Grid and Image menu, select Gridding|From Control File and then select

Bi-Directional Control File. The Bi-directional gridding dialog is displayed.


2. Specify the Data channel to grid (magedited) from the drop down menu. Also

specify a name for the New grid file (tfmag_con). We will leave the Transverse gradient channel blank as this parameter doesn’t apply to our data. For information on this parameter, click the Help (

) button.

3. The next step is to specify a Control file. Normally you would specify an existing

control file that contains your bi-directional gridding (BIGRID) commands and parameters. However, in this tutorial, since no BIGRID control file exists, specify the name of a new control file to create (tfmag.con). 4. Click the [Edit Controls] button and the Select a default text editor dialog is

displayed.

5. This dialog is only displayed if you have not selected a default text editor yet. Use

the [Browse] button to locate a text editor (like Notepad) and click the [OK] button to display the Edit file using notepad.exe dialog.

6. The ftmag.con file is selected by default, click the [OK] button. The system

displays the control file you specified (tfmag.con) using your default text editor. 7. The control file contains comments that explain how to use the BIGRID

parameters. The rest of the control file is blank. 8. Close the tfmag.con control file and click the [Grid] button on the Bi-directional

line gridding dialog to grid the data and display it in your current project.

116 Tutorial 4: Basic Mapping and Gridding Note:

We did not specify any parameters in the bigrid control file, therefore the grid was gridded using only the intelligent defaults.

Multiple Channel Gridding Use the Multiple Channel Gridding to grid multiple channels using the same gridding method. You can now, very efficiently, create grids of all of your selected data. The Grid Multiple Channels menu displays the new Multiple Channel Gridding dialog. Use this dialog to select multiple data channels to grid. This can be used with Minimum Curvature and Bi-Directional gridding methods. T O G RID M ULTIPLE C HANNELS : 1. Open and select a database with multiple channels. 2. On the Grid and Image menu, select Gridding|Grid Multiple Chanels. The

Multiple Channel Gridding dialog is displayed.

3. Select (highlight) the Database Chanels that you want to grid, click the [Add ->]

button to add the selected channels to the Channels to Grid box. 4. Use the Gridding Method dropdown list to select the gridding method as

Minimum Curvature or Bi-Directional Line Gridding. Accepting the remaining intelligent defaults, click the [OK] button to grid the data channels and display the grids in your current project.


Displaying a Grid There are a number of options for displaying grids; these include displaying single grids, colour shaded grids, ternary image grids, two-grid composites (for shadedrelief maps), three-grid composites (for ternary maps) and four-grid composites. In this example, we will display a single grid. Grids appear in the Project Explorer under "Grids". Opening a grid opens a view of the grid in its own internal "map". A grid map view is just like a real map and can accept any graphics that a map can. It can also be saved as a map, in which case the map will appear in the "Map" section of the project explorer. When displaying grids, you must specify a colour table to use (supplied with the product). You may want to experiment with different colour tables to see how they affect your image. T O D ISPLAY

A

S INGLE G RID

ON A

M AP :

1. Open and select the tfmag.map that we created earlier with a basemap. 2. On the Grid and Image menu, select Display|Single grid. The Place a grid on a

map dialog is displayed.

3. Use the dropdown list (

) or the Browse (

) button to select the Grid name as

(tfmag.grd). 4. To select a Colour table click the Browse (

) button and the Colour table dialog will be displayed. This dialog now includes a [Go to…] toggle button that enables your to toggle between [Go to Working Directory | Go to Geosoft Colour Table Directory] button, which enables you to select a colour table from your current working directory or from the “…\Program Files\Geosoft\Oasis montaj\tbl” directory.

5. We can leave the remaining parameters to the defaults and click the [Current

Map] button. The tfmag.grd grid is displayed as on the tfmag.map.


Recolour Grids Click the Auto-Recolour Grids ( ) button in the Map Tools Bar to toggle the Auto Recolour Grids option on/off. This option recolours the displayed grid area as the grid extents change within a map window (e.g. when zooming or panning). Note that, when turned ON the grid values stay the same. However, as the viewed extents of the grid change; the grid colour is recalculated and redrawn using the entire colour palette over the current displayed grid area. • When this option is ON any changes made to the extents of the viewed grid area will cause the grid to be recoloured based on the grid values in the current viewed area, using the entire colour palette. • When this option is ON all displayed grids will be recoloured when changes are made to the extents of the viewed area. • When Auto Recolour Grids is OFF the grids return to their original colours. The Auto Recolour Grids option is a temporary viewing tool. To save/share a recoloured view of a grid you can Create a Snapshot (see page 120) or print the current map extents.

Tutorial 4: Basic Mapping and Gridding 119 Note:

If the Auto Recolour Grid mode is turned ON when you print, it will apply to the printed page. Either turn OFF the mode when printing or print out a selected area and it will apply the recolouring.

Drag-n-Drop Geosoft Grid Files The ability to drag grid files (*.GRD) from Windows Explorer and drop them into an open project is now included in Oasis montaj. The ability to drag other file types directly from Windows Explorer and drop them into Oasis montaj for display is also available including; database files (*.GDB), map files (*.MAP), and s can also drag XYZ files and drop them into an open database file (*.GDB). Items on the Project Explorer bar may also be dragged and dropped.

Plotting Contours Contours refer to the lines drawn at specified intervals or multiples of intervals on your map based on a gridded dataset. After you create a grid, you may want to contour your data and display these contours on your map. In Oasis montaj, contouring is specially designed to handle the very large dynamic data ranges that characterize Earth Science data sets. For more information on plotting contours, refer to the Adding Contours to Maps topic in the Online Help system. Contouring options include quick, custom, log and from a control file (for batch contouring). • Quick - uses default parameters. • Custom - uses parameters you specify the system to use. This method generates simple or log contours. • Log contour - Draws contours on a map using a specified grid in logarithmic mode • Have Control File - ASCII control file enables full cartographic cosmetic control of plotting options In this example, we will use the automatic (quick) method. T O Q UICK C ONTOUR

A

G RID :

1. Make sure the tfmag.map is open and selected in your project. 2. On the Map Tools menu, select Contour and then select the Quick. The Contour

dialog is displayed.

120 Tutorial 4: Basic Mapping and Gridding 3. Click the Browse ( 4.

) button to select the grid you want to contour (tfmag.grd).

Click the [OK] button. The contours are drawn on the map.

Snapshots Use the Manage Snapshots dialog, found on the Map menu, to open, rename or delete your map snapshots.


Map snapshots (or bookmarks) are saved views of the map extents, based on the coordinate system and units of the map view. Map snapshots enable you to return to a favourite location on your map quickly and easily. The snapshot option was designed to help improve your workflow and ease of use. For example, if you are working on a regional scale map and have a number of active project areas (or a number of anomalies in one project area) you can use this tool to quickly and easily zoom into your areas of interest. How to Create a Snapshot The Create Snapshot option can be found on the Map menu, Navigation Bar ( and various Map popup menus.

)

1. Zoom into an area of interest on your current map. Right-click and from the

popup menu select Create Snapshot. The Set Snapshot Name dialog is displayed.

2. Specify a descriptive name for your snapshot and click the [OK] button. The

snapshot will be saved with the current map. How to View a Snapshot Snapshots can be quickly and easily viewed using the dynamic Snapshot menu item on the Map popup menus. 1. Open and select a map that already includes associated “Snapshots”. Right-click,

and from the popup menu select Snapshots. A dynamic sub-menu will be displayed listing all of the snapshots associated with the current map.

2. Select one of the previously created snapshots and your current map will be

redrawn to the extents of the selected Snapshot.


Voxels (3D Gridding) You can create a Voxel using the Voxel Gridding option, located on the 3D menu. A "voxel" is short for "volume pixel" the smallest distinguishable box-shaped part of a three-dimensional image. A Voxel is the 3D conceptual counterpart of the 2D pixel. 3D Menu

The 3D menu includes options for creating, displaying, processing, analyzing, converting, importing and orientating 3D grids. The Voxel Viewer provides additional 3D viewing tools, for more information click the Help menu in the Voxel Viewer. For more information on working with 3D Views, see page 245. Create a Voxel Grid Use the 3D|Voxel Gridding menu option to perform 3D Gridding, which will use a basic statistical kriging algorithm to create a 3D voxel grid from 3D data contained in a Geosoft database (GDB file). The data to be gridded must have defined X, Y and Z fields that locate the data within a coordinate system in which Z coordinates are interpreted as positive up. The data used in this example (3D_IP_data.gdb) can be ed, along with this tutorial from our website at www.geosoft.com/resources/tutorials/. Note: When gridding your data it is important to note that if you reduce the cell size by half then both the file size and processing time are increased by 8 times (2 cubed). T O C REATE 3D V OXEL G RID : 1. Open a database (3D_IP_data.gdb) that includes defined X, Y and Z fields that

locate the data within a coordinate system in which Z coordinates are interpreted as positive up.

Tutorial 4: Basic Mapping and Gridding 123 2. On the 3D menu, select Voxel Gridding. The 3D Gridding dialog will be

displayed.

3. Using the dropdown list, select the Data to grid from the currently open database

as (IP_Avg). Note that a default Output voxel file name will then be provided (3D_IP_data_IP_Avg.geosoft_voxel). You can rename the output voxel file or accept the default name. 4. The Cell size can be left to the intelligent defaults. To determine the default value,

click the Calculator ( ) button. Note that, if you reduce the cell size by half then both the file size and processing time are increased by 8 times (2 cubed).

124 Tutorial 4: Basic Mapping and Gridding 5. Clicking the More (

tabs and click the Less (

) button displays the Advanced and Variogram ) button to hide the tabs.

Tutorial 4: Basic Mapping and Gridding 125 6. When you are satisfied with your selections click the [OK] button and the Voxel

will be created and displayed in the Voxel Viewer.

7. The Voxel Viewer provides additional viewing tools, for more information click

the Help (

) menu on the Voxel Viewer.

When you are done, close the Voxel Viewer and the database (3D_IP_data.gdb). Working with Array Data When working with Array data there are a number of Array tools available on the Array channel popup menu. TO

ACCESS THE

A RRAY T OOLS :

1. Open the Array data database (3D_IP_data.gdb).

126 Tutorial 4: Basic Mapping and Gridding 2. Select the Array Header Cell (e.g. IP) and right-click. The Array channel popup

menu will be displayed.

3. You can use the Array to Database Channels option to to select Array channels to

be displayed as standard database channels. For more information click the ( button on the dialog of interest.

)

Close and Save Project The next tutorial (Tutorial 5: Map Editing and CAD Tools) is designed to introduce you to basic map editing and CAD tools. In order to preserve your current databases and maps we will save and close this project. We will open this project to use again in Tutorial 6: Imaging and Dynamic Linking.


Closing a project will save all of your project databases, maps and profiles, plus information that tells the system whether you are working on a map or profile and the state in which you left it the last time you used it. T O C LOSE

A

P ROJECT

1. On the File menu, select Project and then select Close. The Save Modified

Documents dialog is displayed.

2. This dialog enables you to select All, None or Selected (highlighted) files. To

select more than one file at a time hold the <Shift> key to select consecutive files or hold the key to select individual files. 3. For this tutorial, click the [All] button to save all open databases, maps and grids

in the project.

Tutorial 5: Map Editing and CAD Tools 129

Tutorial 5: Map Editing and CAD Tools This tutorial is designed to introduce you to the basic map editing and CAD functions in Oasis montaj. The procedures are designed to show you how you can use these tools to draw an interpretation from geophysical data. The tutorial also shows how you can use the clipboard to copy, import, and export map groups and images. This tutorial will show you how to: • Display an interpretation map • Create a group • Hide, move, or mask a group • Create and apply a mask • View and edit groups • Draw lines on a map • Convert lines to polygons • Use the “Snap to line” and “Snap to point” tools • Change line symbols and polygon patterns • Using the eyedropper and fill tools • Using the Polygon Edit Tools • Use the clipboard to copy, import and export map elements

Before you Begin This tutorial uses a background map called mag.map. These files are provided on the CD-ROM in the Oasis montaj/data/various directory. Before you begin this tutorial you will need to copy the background map to a working directory and create a new project.

Create a Project In order to begin working in Oasis montaj you must have an open project. The procedures below describe how to open a new project. T O C REATE

A

N EW P ROJECT :

1. On the File menu, select Project and then select New. The New Project dialog is

displayed. 2. Specify a name and directory for the project. For example, name the project

Interp and specify the working directory as D:\Tutorial\cad. Oasis montaj will automatically look for your data in the directory containing this project. Make sure you copy the sample data file (mag.map, mag.grd and mag.GRD.gi) for this tutorial to your project directory (D:\tutorial\cad). 3. Click [Save]. The system saves the project with the corresponding name.

130 Tutorial 5: Map Editing and CAD Tools

Displaying an Interpretation Map Now that you have opened a project, you can display the map you want to interpret. 1. On the Map menu, select Open map the Open Map dialog box is displayed. Select

the mag.map file in your project directory (C:\tutorial\cad). Click the [Open] button to select the file. 2. The map which includes a geophysical grid will be displayed in the map window,

C:\tutorial\cad\mag.map

Note: If you would like to change the colour pallet of your grid to pastel, as shown above, simply redisplay the mag.grd file using the Colour table as (pastel.tbl) or while in Map Group Mode (click the (

) button) select the grid, right click and

from the popup menu select Image Colour tool. Use the Load from File icon ( ) to display the Load Aggregate dialog. Click the [Go to Geosoft Colour Table Directory] toggle button and select the pastel.tbl from the “…Oasis montaj/tbl” directory. Click [Open] and then [OK] on the Image Colour tool, the grid will be displayed using the pastel colour table. (Note, if the grid is not redrawn on closing the Image Colout Tool. click the Redraw ( ) button on the Map Tools Bar, and the grid will be refreshed, displaying the pastel colour table.

Understanding the Parts of a Map In Oasis montaj, Maps are special items that serve a number of purposes in the system. First, the map window provides the basic mechanism for creating maps, images and linking to other maps and data. Secondly, Maps provide a means of editing graphics, adding text and creating highly customized final presentations for output to printers and plotters. To work effectively with maps, you need to be familiar with the purposes of maps in the system as well as the role of views and groups.


Base and Data Views Geosoft Maps use Views to organize and display information. A view divides the information on a map into a Base view, which uses paper coordinates and a Data view, which uses ground coordinates. Map surrounds, north arrows, and scale bars are examples of map groups plotted in the Base view. Map coordinates, contours, and grids are examples of map groups that are plotted in the Data view. 3D Views A 3D View can include data from an existing 2D View or Group already displayed on a map and 2D grid files. Like 2D Views, a 3D view also represents coordinates, but in this case in X,Y AND Z. 3D Views may also contain any number of drawing planes. Any Group or drawing object that can be drawn on a 2D View can be drawn on a Plane in a 3D View. Each plane in a 3D view can be oriented independently in the 3D coordinate system. A Plane in a 3D view can be flat or it can have a surface relief defined by a grid file. The3D Viewer provides all of your 3D-mapping tools, functions and settings in one integrated 3D environment. The 3D Viewer enables you to change the orientation of the 3D View, relative to your point of view, by rotating the coordinate system horizontally and vertically and by zooming and panning. The 3D View can be modified using the 3D Tools, including defining the orientation, setting relief grid controls and transparency levels of individual planes, and specifying axis labels. For more information on creating and working with the 3D Viewer see Tutorial 14: 3D Viewer page 245. Groups Oasis montaj uses Groups to determine the order in which objects are displayed (rendered) on a map. Examples of Groups in the Base view include a north arrow, title text box, or a scale bar. Examples of Groups in the Data view include lines, polygons, grids, and images. You can create, edit, move, hide, and mask groups. You can also move groups in front and behind each other. Any new object you add to a map, such as a polygon or line, is added to the current group. View/Group Manager Tool You can use the View/Group Manager tool ( ) to display and edit the Views and Groups in a map. This tool (see example below) consists of a ‘tree’ structure that contains branches representing the Base views and the Data views. Under each view, a number of groups are listed according to their layer on the map.


Each group in a view shows an icon beside its name that identifies the group as either a map vector object ( ) or an aggregate ( ) . Views can either be normal 2D views ( ) or 3D views ( visibility of an item.

). The check boxes in the tree controls and indicates

To select single items in the tree click on the item desired. Multiple selections of groups within a view can be achieved by holding the key and clicking on the desired items. Changing the selection during group editing will end group editing without cancelling any current changes. The effect of a double click on any item depends on the state of the map. If in shadow cursor mode the map will switch to either group or view selection mode and select the item that was clicked upon. If the map is already in either of these selection modes a button or using the activate double click has the same effect as hitting the shortcut key (default <Enter> key). The group on the top layer (closest to the front) is listed first, followed by the next layer behind it, followed by the rest of the layers to the bottom layer at the end of the list. It is possible to control the render order in the tree by using the Drag n Drop technology. The Drag n Drop capability enables you to move map groups up and down within Views and also to move Views relative to each other. R ENDERING O PTIONS

Check the Render images first box to render (draw) the images groups first. Check the Auto-Redraw box to automatically redraw the map when a change is made to it.


Click the Redraw button to redraw the map when changes are made to the groups in the View/Group Manager and the Auto-Redraw option is off. Frozen Scale Click this button to freeze the scale of the currently selected map group, independent of the view scale of the map. For example, when zooming in the text size in a group will not grow but remain the same size on the screen. Visible Scale Click this button to set a scale range in which the currently selected Group will be visible. For example, individual groups may be made visible only at specific scales. Then, while zooming, if the map scale is outside the range, the group is not drawn.

The View/Group Manager Tool is a “modeless” dialog, which means it can remain open while you work on your map. It can be toggled on or off using the “M” hot key and can even be docked on the side of your screen or at the top with the toolbars. O THER T OOL O PTIONS

The other Tool options include moving, masking, transparency settings, editing and deleting. All of the following properties require the licensed version. Moveable Check the Moveable box to enable the movement of the selected group on the map using the cursor. Masked to View Check the Masked to View box to mask the selected view using the mask applied to the View (Map Tools|Masking|Apply View Mask VIEWCLIP.GX). This option enables you to apply a mask to selected groups within a View. Mask to Group region Using the Mask to Group region dropdown list, select the extended view mask applied to the View (Map Tools|Masking|Add|Replace group mask in view - VIEWEXTCLIP.GX). This option enables you to save the mask into the map and activate it on specific groups in the View. Transparency Check the Transparency box to enable the slider (Transparent - Opaque). Move the slider to the transparency level wanted for the selected group. Edit Click the button to edit (or activate) the selected item. Note: Double click on a group or view in a map or using the activate shortcut key (default Enter-Key) will also activate the edit mode for that item. The edit mode depends on the item; group edit mode for vector groups,


image color tool for images and color symbols and 3D Viewer for 3D views. Delete Click the Delete button to delete the selected View/Group. Note: If you delete a group my mistake or make any other undesired changes, you can click the Undo last map change ( ) button on the Standard Toolbar or use the shortcut (Default Ctrl-Z) at any time to undo any changes and revert to the original map.

Create a New Group The following procedure demonstrates how to create a new group. The procedures for moving, hiding and Masking groups are included in later steps of this tutorial. T O C REATE

A

N EW G ROUP :

1. On the Map Tools menu, select CAD Tools|New group. The Create a new empty

group in a view dialog is displayed.

2. Using the View dropdown list, select (data) and in the New group name box,

specify the name as (Interp). 3. Click the [OK] button. The Map Group Editing Bar is enabled.

Selecting and Editing Groups When you create a new group, this group becomes selected and you can edit it. A group is open for editing whenever you see the Map Group Editing Bar displayed. There are two different ways to select another group to edit. M ETHOD 1

The first method is to use the View/Group Manager Tool . This manager tool provides a single dialog that enables you to switch between different groups, change their properties (moveable, hidden, masked), and changing their layering order (move groups to the front or back).

Tutorial 5: Map Editing and CAD Tools 135 U SING

THE

V IEW /G ROUP M ANAGER :

1. First select the map you want to edit and make sure the Map Group Mode (

)

button is selected. 2. On the Map Tools Bar, select the View/Group Manager (

) button.

3. The View/Group Manager Tool is displayed. The currently selected group

(Interp) is highlighted. To switch to another group, click on the group name so that it becomes highlighted.

4. Click the [Edit] button and the group is selected and in edit mode on your map

and the Map Group Editing Bar is displayed. 5. When you are done editing the group, right-click and from the popup menu, select

End Editing. M ETHOD 2

The second method of selecting and editing a group is to use the Mapping popup menu. You may find this method quicker when you are editing and switching between groups frequently. TO

QUICKLY

S ELECT

AND

E DIT

A

G ROUP

1. Make sure the Map Group Mode (

) button is selected. Place your cursor on the map, right-click and from the popup menu, select Groups and then select the name of the group you would like to select (e.g. Data\Interp). Then, right-click on the map again and this time select Edit this group from the popup menu. The


group is selected and in edit mode on your map and the Map Group Editing Bar is displayed. 2. When you are done editing the group, right-click and from the popup menu, select

End Editing.

Hiding, Moving and Masking Map Groups The following three procedures will show you how to control how groups are displayed on a map. Hiding a Group. Sometimes, when you have many groups on a map you may not want to display all of them on your final map. The procedure below shows you how to hide the grid in your map. T O H IDE

A

G ROUP

ON A

M AP :

1. First select the map you want to edit and make sure the Map Group Mode (

)

button is selected. 2. Click View/Group Manager tool button (

).

3. In the dialog box, highlight the group (AGG_mag) you want to hide and remove

the check box from the box directly infront of the icon. . 4. Click [OK]. The grid on the map is hidden from view. To display the group

again, add the check mark back again. 5. You can also make a group hidden or visible by selecting the group in a map,

right clicking and from the popup menu, select Status|Hidden. Moving a Group To move a group around a map with your cursor, you must first select the Moveable option for that group. Once this option is set, you can move the group by selecting it and moving it with the cursor. T O M OVE

A

G ROUP :

1. First you must make sure the Moveable option is set for the group. There are two

methods of doing this: •

One method is to select the View/Group Manager Tool button ( ). Using the Manager tool, select (highlight) the name of the group, then place a check in the Moveable box. Click [OK].


The second method is to select the group in the map by clicking on the group with the left mouse button. Then click the right mouse button. On the popup menu, click Moveable. 2. Now place the cursor anywhere inside the group. The cursor will change into a set of directional arrows ( ). •

3. Holding down the left mouse button, drag the group in the direction you want to

move it. Masking a Group Masking a group involves using a polygon or rectangular mask file to make only a specific area of a group visible. To mask a group, you must first create and apply a mask to a view. You can then use this mask on specific groups in the view areas of the group outside the mask. The following three procedures show you the steps to create a mask, apply it to a view, and turn Masking on for a group. T O C REATE

A

R ECTANGULAR PLY F ILE :

1. On the Database Tools menu, select Window Data, then select Create

Rectangular PLY file. The Define a rectangular plot mask dialog is displayed. 2. Click the [Interactive] button. The Define rectangle dialog box is displayed.

Click the [OK] button to continue.

3. Use the mouse to draw a rectangle on the lower right quadrant of the map

(Mag.map). The Define a rectanglular plot mask dialog is then displayed with the coordinates of the rectangle, as shown in the dialog below.

138 Tutorial 5: Map Editing and CAD Tools 4. Specify the mask file name as rectanglemask.ply and from the dropdown list

select inclusive. This means that when the mask is applied to a group, only features inside the rectangle mask will be visible. 5. Click [New File] to save the mask file. T O A PPLY

A

M ASK

TO A

V IEW :

1. On the Map Tools menu, select Masking, then select ApplyView Mask. The Reset

view clip region dialog is displayed.

2. Using the Browse button, specify the Clip polygon file (.ply) as

(rectanglemask.ply) and select the Map view as Data. In the Clip all groups box, select (yes). This will set the Masking option to on for all the other groups in the view. 3. Click the [OK] button. T O M ASK

A

G ROUP :

1. Select the map you want to edit and make sure the Map Group Mode (

) button

is selected. 2. Click View/Group Manager Tool button (

). In the dialog box, highlight the

group (AGG_mag) you want to mask. 3. Place a check mark in the Masked to View box. Click the Redraw (

) button.

4. The map is redrawn to display only the section of the grid inside the mask.


5. You can also turn Masking on or off by selecting a group in a map, and on the

Map Tools menu, select Masking|Clear View Mask. The mask will be cleared from the View.

Drawing Lines, Polylines and Polygons You can use the line and the polyline tools to draw linear features such as dykes and faults. You can then connect these lines and create shaded polygons to mark different geological or geophysical areas of the site. Drawing Polylines The procedure below shows you how to draw polylines on your map and how to create polygons from these lines. This procedure also shows you how to use the Snap to point and Snap to line tools, which are useful for ensuring that your lines connect each other without overlapping. D RAWING P OLYLINES

TO I DENTIFY

L INEAR F EATURES :

1. Select the mag.map. 2. Make sure the Map Group Mode (

) button is selected. Right-click mouse

button on the map. 3. On the popup menu, select Groups, then select name of the group you would like

to select (Interp). 4. To edit the selected group, right-click on the map and select Edit This Group from

the popup menu. The Map Group Editing Bar is displayed. 5. On the Map Group Editing Bar, click the Polyline tool (

) button.

140 Tutorial 5: Map Editing and CAD Tools 6. Draw a line along the edge of an anomaly. Click cursor on the place you want the

line to start, and then move the mouse, clicking wherever you want to change direction. When you are finished, right click and from the popup menu, select Done.

7. Draw another polyline roughly parallel to the first (as shown below).

8. You can now connect other polylines to the ones you have just drawn. To do this

click on the polyline tool button. 9. Click right mouse button. A dialog box is displayed that enables you to choose

whether you want the new polyline from a location along the existing line or a point on the line. Note: To just draw a line and not connect it to a previous line, select Cancel and left click to draw the line (as you did in step 2 for the first polyline).

Tutorial 5: Map Editing and CAD Tools 141 10. Choose the Snap to point option. The cursor will change to a circle with a shaded

centre.

11. When you move the cursor over a point or node along the line, the cursor changes

to a target symbol with the shaded circle indicating the location of the point.

12. To begin drawing a new polyline from this point, click left mouse button. 13. Move the cursor and click left button to define the shape of the line. Draw the

polyline so your last point is located just short of the second line (see below).

14. Click right mouse button. On the popup menu, click Snap to line. The cursor will

change to a circle. Use this cursor to search for a section of the line to connect to. The Snap to line cursor works like this: • •

When the cursor is searching for a line to connect to, it looks like: When the cursor finds a line it can connect to, it changes to:

15. Once you have the cursor on the line where you want it, click left mouse button to

insert a point. 16. Click right mouse button, and then select Done to finish drawing the line. 17. Repeat the previous steps to add more polylines to your map so that it looks

something like the following:


Changing Line Attributes This procedure shows you how to modify the attributes (thickness, colour and pattern) of the lines you drew in the previous steps. C HANGING L INE A TTRIBUTES : 1. Select the line you would like to edit by clicking the left mouse button on it.

Sizing handles are displayed around the line, indicated it is selected. 2. Right-click and from the popup menu, select Attributes. The Polyline Attributes

dialog box is displayed.

3. In the Thickness box, you can specify the line thickness in millimetres (0.1 is the

default). 4. To change the line colour, click on the Draw Colour box. A colour palette dialog

box is displayed for you to choose a colour.

Tutorial 5: Map Editing and CAD Tools 143 5. To change the line pattern, make sure there is a check mark in Styled Line check

box. Double click in the Styled Line box to display the LineAttributes dialog box.

6. In the Pattern Family box you can select from a variety of different sets of

patterns (Standard Patterns, Fancy lines, Geology, Arrows, Slashes, and Shapes). In the Pattern box, click on the pattern you would like to apply. You can also set the pitch (which is the distance between the symbols or dashes in the line). Click the [OK] button when you are finished. 7. Click Smooth check box to smooth the rough edges in the polyline into smooth

curves. 8. Click [OK] to apply the changes to the line or click [Cancel] to exit the dialog

without making any changes. Creating Polygons from Lines After delineating different areas of your map with polylines and/or lines, you can use these lines to create polygons. This process will convert all the lines in the current group into polygons. If you have lines that you do not want converted to polygons either create these lines in a different group or ensure that the lines are not connected to other lines to create polygons. T O C REATE P OLYGONS

FROM

L INES :

1. On the Map Tools menu, select CAD Tools|Create PLY File from Map Group.

The Create polygon file from group dialog is displayed.


2. Using the Select a View/Group dropdown list, select the View\Group as

(Data\Interp) and then in the Output polygon file box, specify the name of your polygon file as (group_polygon.ply). 3. Click the [OK] button to create a polygon file from your lines in the selected

group. 4. To create fills for the closed polygons, on the Map Tools menu, select Create

Fills for Closed Polylines. The Create a polygon area group from a line group dialog will be displayed.

5. The Line group to process box should contain the group of lines that you want to

convert to polygons. 6. The Use colours or patterns box has three options for shading polygons: colours,

patterns or both. Choose (both) to use both colours and patterns. 7. The number of units indicates the number of boxes of categories you want to

create in the legend. The default is 10. You can edit these boxes later. 8. Select Yes to add a legend to the map. Click [OK] to continue. 9. Specify the legend settings in the Legend dialog box.


10. Click the [OK] button to create polygons and a legend similar to the map below.

E DITING P OLYGONS

AND

L EGEND B OXES :

1. You can edit both polygons and their associated legend boxes in the same way.

While you are in Map Group Mode, move the cursor to the polygon or box you want to edit and double-click the left mouse button. The Polygon Attributes dialog box is displayed.


2. To change the fill colour, click on the Colour box. A colour palette dialog box is

displayed for you to choose a colour. To turn line colouring off (i.e. make the line invisible) remove the check mark from the Filled check box. You can select a line colour the same way using the Draw Edge | Colour box instead. 3. To change the fill pattern, make sure there is a check mark in Fill pattern check

box. Double-click in the Pattern box to display the Pattern Attributes dialog.


4. In the Pattern Family box you can select from three different sets of patterns

(Objects, Hatches or Solid Fill). In the Pattern box, click on the pattern you would like to apply. 5. You can also set the Tile Size and Tile Density, which changes the space between

the pattern symbols and the Line Thickness (% of Tile Size), which changes the size of the individual pattern symbols. Click the [Refresh] button to see what the pattern will look like in the example box. 6. Click the [OK] button when you are finished selecting a pattern or click [Cancel]

to exit the dialog without making any changes. 7. Click [OK] on the Polygon Attribute dialog box to apply the changes to the

polygon or click [Cancel] to exit the dialog without making any changes.


Using the Get Colour and Polygon Colour Tools Using the Get Colour Tool (eyedropper) and the Polygon fill tool (bucket) on the Map Group Editing Bar, you can copy fill colours and patterns from one polygon and apply them to another polygon. A description of each tool and how to use them is provided below. G ET C OLOUR T OOL

You access the Get Colour Tool by clicking on its button in the Map Group Editing Bar. The image cursor will change to an eyedropper.

Button Cursor

P OLYGON F ILL T OOL

You access the Polygon Fill tool by clicking on its button in the Map Group Editing Bar. The image cursor will change to a bucket. T O C OPY

A

C OLOUR

FROM ONE

P OLYGON

1. Click on the Get Colour button (

TO

Button Cursor

A NOTHER :

) in the Map Group Editing Bar. The image

cursor will change to an eyedropper (

).

2. To get a colour (and pattern) from a polygon, place the eyedropper cursor over

the polygon containing the colour you want and click left mouse button. 3. The cursor will change to a bucket (

). Click on the polygon to which you want to apply the fill. The polygon now contains the new colour (and pattern).

Polygon Edit Tools Polygon Edit tools are now provided with Oasis montaj. These tools will enable you to edit polygon vertices, add exclusion regions to polygons, and tools to switch between editing the vertices of main polygons (Islands) and vertices of the exclusion regions polygons (Holes).


Map Edit popup menu

Edit polygon vertices The ability to edit polygon vertices has been added to the Oasis montaj Mapping and Processing System. The Edit Vertices option is available on the “Map Edit” popup menu when you are in Group Edit mode and have a polygon selected on your current map. For instructions on Editing Vertices see To Add/Remove Vertices on a Polygon below.

Polygon Edit Tools

Description Edit Vertices. Use this tool to edit the vertices of a previously created polygon. Add Vertices. Use this tool to add new vertices to a polygon. Delete Vertices. Use this tool to delete vertices from a polyon. Add New Rectangular Island. Use this tool to add a new rectangular “Island” to a previously created polygon. Add New Polygon Island. Use this tool to add a new polygon “Island” to a previously created polygon. Add New N-Sided Polygon Island. Use this tool to draw a new N-sided polygon “Island” to a previously created polygon. Add New Rectangular Hole. Use this tool to add a new rectangular “Hole” to a previously created polygon “Island”. Add New Polygon Hole. Use this tool to add a new polygon “Hole” to a previously created polygon “Island”. Add New N-Sided Polygon Hole. Use this tool to draw a new N-sided polygon “Hole” to a previously created polygon “Island”. Cycle to Previous Hole/Island. Use this tool to cycle (switch) to the previous Hole or Island. Cycle to Next Hole/Island. Use this tool to cycle (switch) to the next Hole or Island. Delete Current Hole/Island. Use this tool to delete the current Hole or Island.


To Add/Remove Vertices on a Polygon Vertices can be added or removed from polygons by using the plus (+) and minus (-) keys on your Number Keypad. Note: The plus (+) and minus (-) keys on the main alpha-numeric keypad will not work; you MUST use the Number Keypad only. T O A CCESS

THE

E DIT P OLYGON V ERTICES O PTION :

1. Click the Map Group Mode (

) button and select the group on your map that includes the polygon you wish to edit.

2. While holding your cursor over your map, right click and from the “Map Edit”

popup menu select, Edit This Group. The group will now be in Edit mode (you will see a box with hatch marks around the group, this is a visual clue that you are in Edit mode). 3. Select the “Polygon” that you want to edit and then right click and from the “Map

Edit” popup menu you can now select Edit Vertices. The vertices on your map will change from grey to white. TO

ADD ADDITIONAL

V ERTICES

ON A POLYGON :

1. While in Edit mode, select Edit Vertices from the “Map Edit” popup menu. 2. Place your cursor, between two vertices on the polygon, where you want to place

the new vertices. Press and hold the “+” key on your Number Keypad (note that, a plus sign (

) is added to your cursor).

3. While holding down the “+” key, use your mouse to select the location for the

new vertices. 4. Or, you can select the Add Vertices button on the Polygon Edit Bar. Your cursor

will change to a cross-hair and it will be linked to the polygon lines. Left-click to add new vertices to the polygon. TO

REMOVE VERTICES FROM A POLYGON :

1. While in Edit mode, select Edit Vertices from the “Map Edit” popup menu. 2. Place your cursor on the vertices you want removed. Press and hold the “-” key

on your Number Keypad (note that, a vertices selection box and a minus sign are added to your cursor). 3. While holding down the “-” key, use your mouse to select the vertices to be

removed. 4. Or, you can select the Delete Vertices button on the Polygon Edit Bar. Your

cursor will change (vertices selection box and a minus sign added). Left-click to delect vertices from the polygon.


Using the Windows Clipboard with Maps in Oasis montaj The Windows clipboard can be used to move maps and map component objects from one map to another within Oasis montaj. In addition, you can use the clipboard to copy and paste objects between Oasis montaj and other applications. The Windows clipboard lets you perform the following tasks: • Copy text and graphics (as EMF objects) from Windows applications to Oasis montaj maps. • Copy map objects from Oasis montaj to the clipboard as EMF picture graphics and bitmaps. You can then paste these pictures into most word processing, presentation and graphic applications. • Copy objects from one map to the clipboard and paste these into another map. The objects can be pasted either as georeferenced information in an existing data view, or in a separate view centreed on the currently displayed window. How does the Windows Clipboard work? The Windows clipboard allows applications to perform two separate operations: 1. Information can be copied (or cut) to the clipboard. 2. Information on the clipboard can be pasted into an application document.

When information is copied to the clipboard, it can be placed on the clipboard in a variety of formats. When information on the clipboard is pasted into another application, that application will choose a format on the clipboard that it understands. For example, when text is copied to the clipboard from the Microsoft Word program, it is placed as raw ASCII text, a formatted EMF picture of the text, and a Word document that includes formatting information. When this information is pasted into a simple text editor, only the ASCII text can be used. When this information is pasted onto a PowerPoint slide, the text and formatting is used, and when pasted onto an Oasis Montaj map, the EMF picture is used. When information is copied from an Oasis Montaj map to the clipboard, the following will be placed on the clipboard: • A text block that contains geo-referencing information about the object. This includes the locations of the corners of the picture formed by the information and the map projection of the coordinate system. • A map view and its contained groups, or all map groups if nothing on the map was selected. If a map group was selected, only that group and the view that contained the group are placed on the clipboard. • An EMF picture of the map or view/group selected and clipped to the currently displayed window. • A bitmap of the map or view/group selected and clipped to the currently selected window.


Copying Georeferenced information between Maps All data plotted in a map data view carry with it the geo-referencing information of the view. Georeference information includes the map coordinates of the data, a transform that translates the view coordinates to the map (paper) coordinates, and optionally a full map projection. When data is copied to the clipboard, all this information is included. If you use the paste georeferenced command to paste the clipboard information into a map view on another map, the geo-referencing information will be used to locate this information correctly in the new data view. If the new data view is in a projection different from the original data view, the data will be re-projected to the coordinate space of the new view. T O C OPY G EOREFERENCED O BJECTS (G ROUPS )

BETWEEN

M APS :

1. On the first map, select the entire map, a view or a group you want to copy. •

To select the entire map, make sure you are in the normal cursor tracing mode by clicking the Shadow Cursors button (

).

To select a view, click on the Map View Mode button . Then click on the view you want to select. • To select a group, click on the Map Group Mode button , then choose the group. • To select a single entity within a group such as a single line or polygon, click on the Map Group Mode button . Then double-click on the group to change to the group edit mode (or select the group, right-mouse button, “Edit this group”). Once in group edit mode, select the entity you want to place on the clipboard. 2. Click the right mouse button. On the popup menu, click “Cut”, “Copy”, or “Copy map to clipboard” (if displayed), or (or press CTRL+C). •

3. Click on the map you want to paste the information into. 4. Click on the right-mouse button and select paste georeferenced. You will be

presented with a dialog that lets you choose the view that you want to paste the information into. Use the Clipboard to create a Montage Map or Poster At times, you may want to make a single map that contains separate data views from multiple map presentations. This is often called a montage. Each data view may show different data for the same map area. This can be done using the cut and paste feature of Oasis montaj as follows: T O C REATE

A

M ONTAGE M AP

FROM COMPONENT MAPS

1. Create separate maps of all the different data sets that you want to show together

on your montage.

Tutorial 5: Map Editing and CAD Tools 153 2. Create a new empty map that will be the montage. It is easiest to create this map

by duplicating an existing map without its contents. From the Map menu, select Duplicate map and specify a new map name and make the contents “blank”. The blank map that is created will be your montage map. 3. Go to a map that contains data and select the data by changing to the Map View

Mode mode (button ), then click on the view you want to select. Click the right mouse button and choose “Copy” (or press CTRL+C). 4. Go to the montage map, click the right mouse button, on the menu click Paste.

On the dialog that is presented, choose the Same scale at offset option and specify a location at which to place the view on the montaj map. You can also simply move the view after pasting. 5. Repeat steps 3. and 4 for each data view to be placed on the montaj map.

When working with a montage map, you can also turn on the Map/Snap mode to limit the location of moved items to an even increment from the map origin. This helps you to exactly line up map views vertically and horizontally. Use the Map/Snap resolution option to specify the smallest increment to use for moving views. You might also choose to create your montage map from the entire contents of other maps, including their base views. To do this, choose Copy map to clipboard instead of “Copy” in step 3. In step 4, always choose to offset the location of the inserted views as required. This is because once inserted, only individual views can be selected and moved on the map and it is difficult to move all map views and keep the alignment between views. Using the Clipboard to paste a picture from another application on a Map You can use the clipboard to paste an image onto a map from another application that can copy Enhanced Metafile Format (EMF) or Bitmap information to the clipboard. For example, you might create marginal notes for your map in Word for Windows. This information can be selected and copied to the clipboard, where it will be in EMF format (among others). This information can then be pasted on your map, sized and located as you like. T O P ASTE

A

P ICTURE

FROM ANOTHER

A PPLICATION

TO A

M AP :

1. In the other program, select the graphical information and copy it to the clipboard

(in Word, just select the text, or in PowerPoint, select a slide or an object on a slide). 2. In Oasis montaj, select the map you want to paste the graphic into. 3. Click on the right-mouse button and select paste. You will be presented with a

dialog that lets you choose the view that you want to paste the information into


Using the Clipboard to export a graphics from a Map to another application You can use the clipboard to copy maps, or parts of maps to other applications that can accept EMF or Bitmap graphics, or can understand Oasis Montaj map objects on the clipboard. For example, you may wish to place your data view and the images it contains on a PowerPoint slide, or add this as a figure in a Word for Windows document. T O P LACE

A

G RID I MAGE

ON A

P OWER P OINT S LIDE :

1. In Oasis montaj, display the grid in a data view and add whatever other graphics

you want to include. 2. Click the Map View Mode button (

) and choose the view you want to place in

PowerPoint. 3. Click on the right-mouse button and select “Copy” (or press Ctrl-Insert). 4. In PowerPoint, create a new slide, or open the slide to receive the picture. 5. In PowerPoint, on the Edit menu, click Paste Special. This will display a dialog

box enabling you to choose the format that you want to use to paste the image. Choose “Picture (Enhanced Metafile)”. Note: You can use the same procedure in almost any Microsoft application. Other applications that pasting of Enhanced Metafile or Bitmap information will have a similar procedure.

Close and Save Project The next tutorial (Tutorial 6: Imaging and Dynamic Linking) is designed to introduce you to imaging and dynamic linking and we will be using the data and maps from Tutorial 4. Therefore, we need to close the current project. Closing a project will save all of your project databases, maps and profiles, plus information that tells the system whether you are working on a map or profile and the state in which you left it the last time you used it. T O C LOSE

A

P ROJECT

1. On the File menu, click Close|Project. The Save Modified Documents dialog box

is displayed. 2. Click the [All] button to save all open databases in your project. (Maps are always

saved when you close a project.)

Tutorial 6: Imaging and Dynamic Linking 155

Tutorial 6: Imaging and Dynamic Linking As described in Tutorial 3, the system provides a variety of capabilities for imaging and linking maps to data and profiles. This tutorial introduces you to these concepts. Before you begin… In this tutorial will be using the data and maps from Tutorial 4. Therefore, we need to open the GeoDemo project. T O O PEN

A

P ROJECT

1. On the File menu, select Project and then select Open. The Open Project dialog

box is displayed. 2. Select the GeoDemo.gpf file and click the [Open] button. The project is open

exactly as you left it.

Creating Colour Shaded Images The shaded relief image is a common method used to present geophysical and other types of data. This presentation technique creates a 3-dimensional effect using 2dimensional rendering or plotting capabilities. The result is useful for checking the quality of the data and for data interpretation. When you create a shaded relief map the system automatically creates a new grid file for that map with _s after the original grid name. For example, mag.grd will become mag_s.grd. Shaded relief maps can be created interactively using the Run Dynamic Shawdowing button ( ) in the Image Colour Tool, or manually by creating a shaded grid using the Grid and Image|Display|Colour-Shaded Grid. T O C REATE

A

C OLOUR S HADED I MAGE :

1. On the Grid and Image menu, select Display and then select Colour-Shaded Grid.

The system displays the Colour-shaded grid image dialog box.

156 Tutorial 6: Imaging and Dynamic Linking

2. Click the [Browse] button to select the Grid name (tfmag.grd). For the Shading

effect select Normal (RGB) from the drop down menu. Accept the default parameters for the Colour table, Colour method, Illumination inclination and Illumination declination. Note: The illumination inclination and illumination declination simply means the sun illumination angles. 3. Click the [New Map] button. The Map Exists dialog is displayed.

4. This is a safety feature built into the system to make sure that you that you do not

overwrite your tfmag.map. Click the [No] button so that you do not overwrite your current map. The system prompts you for a New map name.

5. Type the name of the new map as tfmag_shaded.map. Click the [OK] button.

The system will create a colour-shaded image from the grid file tfmag.grd and place the image in a new map window called tfmag_shaded.map.

Tutorial 6: Imaging and Dynamic Linking 157

Interactive Colour Imaging and Shadowing Oasis montaj provides an Image Colour tool that enables you to modify colour grid zoning interactively on the screen, store custom colour configurations in a specialized colour palette file and apply these to all of your grid image products. The system s the following transform methods for zoning the data. • Linear - The system divides the range of grid values linearly into even increments. • Normal - The system assumes your grid data are normally distributed and determines zones based on the distribution for a standard bell curve. • Equal Area (Histogram) - The system evaluates your grid values and statistically determines the zones, such that each colour occupies an equal area of the map. T O A CTIVATE

THE I MAGE

C OLOUR T OOL :

1. Make sure tfmag_shaded.map is selected in your project. 2. Click the Map Group Mode button (

).

3. Since there is only a colour shaded image in this map and no other groups, click

on the map once with the left mouse button to have the system select the map. You will notice that the cursor has changed to show that it is in the Map Group Mode.

158 Tutorial 6: Imaging and Dynamic Linking

4. Right click while your have the grid selected and from the popup menu select

Image Colout Tool. The Colour Tool dialog is displayed. This dialog shows the data distribution relative to the colour table (colour.tbl) selected earlier.

T O M ANIPULATE

THE

C OLOUR S PECTRUM / P ERCENTILE G ROUPS :

1. Press and hold your left mouse button on the left or right arrows at the top corners

of transform box. This will expand or contract your view of the transform in the window.

Tutorial 6: Imaging and Dynamic Linking 159 2. Click on the up or down arrows on the colour slide bar and notice how the colours

compress and stretch through the data range. The percentile value is displayed on the right-hand side of the colour tool bar. Also notice how the colour values change at the same time on your tfmag_shaded.map. Click the [Reset] button ( T O A CTIVATE

) to set the colours back to their original settings.

THE I NTERACTIVE

C OLOUR S HADING T OOL :

1. Ensure that the Image Colour Tool is still activated. 2. Select tfmag_s.grd as the image to be used by the Image Colour Tool from the

dropdown menu that displays the current grid name.

3. A new image transform is displayed for the tfmag_s.grd. 4. Click the [Dynamic shadowing] button (

). The system displays the Shadow

Tool dialog box.

5. Move the Shadow Tool dialog box so that it’s not blocking the map. 6. Click the [DynaShade] button. Your cursor will turn into a sun icon (

).

160 Tutorial 6: Imaging and Dynamic Linking 7. Use the sun cursor and click and hold the left mouse button on the image. As you

move your mouse around the image, the sun illumination will change relative to the centre of your map window. Note: The illumination is relative to the centre of the map window and not the centre of the image. 8. To save your new sun angles, release your mouse button and click the [Stop] button, then click the [OK] button. 9. The system returns you to the Image Colour Tool dialog box. 10. Click the [OK] button to save your changes.

Copying and/or Converting Grid Files Oasis montaj enables you to copy and/or convert any ed grid format to any other ed grid format. C OPYING

AND / OR

C ONVERTING G RID F ILES

1. On the Grid and Image menu, select Utilities|Copy/Convert. The Copy/convert

grids dialog is displayed. 2. Using the [Browse] button, select the Input Grid File, and specify the Output

Grid File. 3. Click the [OK] button. The grid is copied and/or converted as specified. Note:

For more information on copying and /or converting grid files, click the Help (

) button on the Copy/convert grids dialog box.

Using Dynamic Data Links Dynamic links are “virtual” georeferenced connections between spreadsheets, profiles and maps. These links work in two-directions so you can select any window and see the equivalent data in the other windows you are using. T O L INK S PREADSHEET , P ROFILE

AND

M AP D ATA:

Desktop linking enables you to place a special Link cursor on one or more maps and locate a specific part of the data. 1. Make sure only tfmag_shaded.map and the database tfmag.gdb are open in your

project (do not remove them from your project, just close the map, grid and database windows of the other items). 2. On the Window menu, click Tile Vertically. The system arranges your database

window and map window side by side. 3. The system automatically turns on a map link and activates the Shadow Cursors

). You can tell a button is activated button on the Map Editing toolbar. ( because it will appear to be depressed more than the other buttons on the toolbar.

Tutorial 6: Imaging and Dynamic Linking 161 4. Click on a value in the database or on a point in the profile view, and you see that

the Link cursor (large black cross) moves to the same location on the map. This type of linking enables you to quickly identify discrete anomalies on a map and view their corresponding values in the database. 5. You can display multiple maps and use this function to locate and visualize the

same anomaly locations for different data types. It is quite useful for quality control (searching for anomalous noise spikes, for example) and for multiparameter interpretation.

Dynamic Data Linking

162 Tutorial 7: Creating Custom Base Maps

Tutorial 7: Creating Custom Base Maps Many s have the need to create custom base maps based on corporate standards or client requirements. Custom base maps can be prepared using the commands available in the MAPPLOT GX. In this exercise, we will build a MAP using the control file, Map04.con, along with a few files. T O C REATE

A

C USTOM B ASE M AP :

1. On the Map Tools menu, select Base map and then select Mapplot Control

File|From Control File. The MAPPLOT control file and load on current map dialog is displayed.

2. Click the [Browse] button and select the Control file name, (Map04.con). From

the Draw to dropdown list select a new map. We can leave the Match strings blank, for more information on match string, click the Help ( 3. Click the [OK] button and the New map dialog is displayed.

) button.

Tutorial 7: Creating Custom Base Maps 163 4. Specify the New map name as (Map_04) and click the [OK] button. The new

map with the basemap based on the Mapplot control file (map04.con) is displayed.

5. The control file Map04.con is shown below. To view the control file, on the Edit

menu, select Edit a file. Click the [Browse] button to locate the control file. The four letter commands (for example, SURR) are all described in the help for the MAPPLOT GX. This file accesses several text files for legend information: survey.leg and mag.leg. It also places three images on the map: a Geosoft format grid file, map04mag.grd; a TIF file, omontaj.tif (Oasis montaj logo); and a JPG file, indexmap.jpg. MDFF map04.mdf DATT s1=kt100 DATT s2=kt200 DATT s3=kt500 DATT t1=kt100 DATT t2=kt200 DATT t3=kt300 MGRP Surround,0,0 SURR s3,0.15,s1 DATT s1

164 Tutorial 7: Creating Custom Base Maps MGRP Coordinates,0,1 ANOY ,,,,,2000,0.15,,-1,-1,,,-0.15,,1 ANOX ,,,,,2000,0.15,,-1,,,,-0.15,,1 DATT refgrid=kt150 GRID 2 PROJ DATT GRID ALAT ALON

map.PRJ llgrid=kt050 -3,0.05,0.0230 ,,0.5,,,-1 ,,0.5

DATT RECT MGRP SCAL SCAL

s1 12 Scale_Bar,0,0 1,6,2,,ft,,,,1 1,6,3,,mt

MGRP North_Arrow,0,0 NARR 9,-6,-4,0.0,4,s2,80.3,23.4 MGRP Index_Map,0,0 RECT 3,-10,7,-2.65,15 TEXT 3,-9.8,7.2,-1,"Index Map - Topography" s1,,,,,TI RECT 3,-8,10,-6,13 s3 TEXT 3,-8.2,9.7,-1,"Survey Area" s1,,,,,TI MGRP Color_Bar,0,0 CBAR 6,-14,-8,1.2,0.6,s1 mag.agg,,,,-1 "Magnetics" "[nT]" DATT s1 MGRP Legends,0,0 TXTB 3,-6,20,0,,mag.leg s1 TXTB 3,-10,30,-1,,survey.leg s1 MGRP Titles,0,0 TITL 3,0,0,12 a,"Goldhunter",0,t2,.4 b,"Total Field Magnetics",0,t3,.3 b,"Northern Province",0,t2,.3 b,"Canada",0,t2,.3

Tutorial 7: Creating Custom Base Maps 165

MGRP AGGR

MGRP AGGR

MGRP AGGR

c,"Data collected by ",0,t1,.25 c,"Helicopter Magnetics System",0,t1,.25 c,"flown by",0,t1,.25 c,"Surveys 'R Us",0,t1,.25 d,"Gold Mapping Corp.",0,t2,.3,,,15 Mag,0,1 0 AGG_mag mag.grd,colour.tbl,3 Logo,0,0 2,-5,1,18,6,1 AGG_logo omontaj.tif(IMG;t=tif) IndexMap,0,0 3,-10,7,36,15,1 AGG_indexmap indexmap.jpg(IMG;t=jpg)

6. Open map04.con file in your text editor program (i.e. Notepad). 7. Experiment with the map04.con file. Adding a forward slash character “/” at the

start of a line changes the line to a comment. If a line has this type of character you can add any text for your informational purposes. Add a forward slash character “/” to the following lines at the end of the file. /MGRP IndexMap,0,0 /AGGR 3,-10,7,36,15,1 /

AGG_indexmap

/

indexmap.jpg(IMG;t=jpg)

8. Save the changes you made to the map04.con file as map04_no-index-map.con. 9. Create a new map using MAPPLOT, following the procedure in Step 1 above,

substituting map04_no-index-map.con for the control file name, and map04_-map.map for the map name. The indexmap JPG image (brown topographic map) will be missing. 10. Try other modifications. Click the Help (

) button from the MAPPLOT control file and load on current map dialog box. You can add any commands found in the MAPPLOT GX to the control file.

Tutorial 8: Batch Processing with Scripts 167

Tutorial 8: Batch Processing with Scripts Scripting refers to the act of creating and running a file that will carry out many operations in a row. Oasis montaj Scripts are ASCII files that define a series of processing actions to be performed on selected data in a database. You can run scripts interactively in Oasis montaj using the script toolbar buttons Scripting commands found under the GX menu.

or the

We will create a script file using the script file record option. This operation writes a script file (*.GS) by recording each GX that you run during this session – until you stop script recording (from the GX menu). The resulting (*.GS) file contains sufficient parameter and database information to run the selected GXs in the same sequence. We will try this by recording a script of three different GXs - create a map using MAPPLOT, add line path, and add line profiles - then run the file. For more information on using Scripts, see the Creating Scripts In Oasis montaj Technical Note, available online at: www.geosoft.com/resources/technotes/ T O C REATE

A

S CRIPT F ILE :

1. On the GX menu, select Scripting |Record Script. The Create Script File dialog is

displayed.

2. Specify a File name (Script_map) and then click the [Save] button. 3. On the Map Tools menu, select Base Map|MAPPLOT control file and then select

From Control File. The MAPPLOT dialog is displayed.

168 Tutorial 8: Batch Processing with Scripts 4. Using the [Browse] button for the Control File Name parameter, select the

control file map04.con. Then, from the Draw to dropdown list, select a new map. 5. Click the [OK] button and the New map dialog will be displayed.

6. Specify a New map name as (Script_map), and click the [OK] button and the

new map (Script_map.map) will be created and displayed in your current project. 7. On the Map Tools menu, select Line Path. The system displays the Line path plot

dialog box. The default settings will be used for this tutorial. Click the [OK] button.

8. On the Map Tools menu, select Profile. The Profile plot dialog is displayed.

Tutorial 8: Batch Processing with Scripts 169

9. Specify magedited from the dropdown menu for the profile channel, 50 units/mm

for the profile scale and 5000 for the profile base. Specify blue from the dropdown menu for the line colour. Click the [OK] button. 10. On the GX menu, click Stop recording.... The system stops recording your

actions. All of your actions were recorded and saved to the script_map.gs file. 11. On the Edit menu, click Edit a File. The Edit file dialog is displayed.

12. Click the [Browse] button and select the file Script_map.gs as the File you wish

to open to view the Script parameters that you just created. Click the [OK] button and the system opens up the file in your default text editor. Below is the Script_map.GS file. The three GXs that were recorded are shown beside the GX command: MAPPNEW, PATH, and PROFILE. For information about the scripting commands, please use the Help system and look under script commands. /-------------------------------------------------------/ LOG OPENED : Wed Mar 17 00:55:00 2004

170 Tutorial 8: Batch Processing with Scripts /-------------------------------------------------------CURRENT Database,"D:\Tutorial\tfmag.gdb" CURRENT Map,"d:\tutorial\Map_04.map" SETINI MAPPLOT.CON=".\\map04.con" SETINI MAPPLOT.NEW="1" SETINI MAPPLOT.MS1="" SETINI MAPPLOT.MS2="" SETINI MAPPLOT.MS3="" SETINI MAPPLOT.MS4="" SETINI MAPPLOT.MS5="" SETINI MAPPLOT.MS6="" SETINI MAPPLOT.MS7="" SETINI MAPPLOT.MS8="" SETINI MAPPLOT.MS9="" SETINI MAPPLOT.MS10="" SETINI MAPPLOT.MAP=".\\Script_map.map" GX mapplot.gx CURRENT Database,"D:\Tutorial\tfmag.gdb" CURRENT Map,"d:\tutorial\Script_map.map" SETINI PATH.LINE_COLOR="K" SETINI PATH.LINE_THICKNESS="0.15" SETINI PATH.TICKFLAG="0" SETINI PATH.LABEL_FORMAT="TL" SETINI PATH.LABEL_DIR="0" SETINI PATH.LABEL_COM="0" SETINI PATH.LABEL_LOCATION="1" SETINI PATH.LABEL_SIZE="2.5" SETINI PATH.LABEL_COLOR="K" SETINI PATH.LABEL_WEIGHT="0" SETINI PATH.H_OFFSET="2" SETINI PATH.V_OFFSET="0" SETINI PATH.GAP="0" GX path.gx CURRENT Database,"D:\Tutorial\tfmag.gdb" CURRENT Map,"d:\tutorial\Script_map.map" SETINI PROFILE.CHANNEL="magedited" SETINI PROFILE.SCALE="50" SETINI PROFILE.BASE="5000" SETINI PROFILE.LOG="0" SETINI PROFILE.LOGBASE="1.0" SETINI PROFILE.SMOOTH="0" SETINI PROFILE.COLOR="CM" SETINI PROFILE.THICKNESS="0.15" SETINI PROFILE.STYLE="0" SETINI PROFILE.PITCH="5" SETINI PROFILE.PFILCOL="N" SETINI PROFILE.NFILCOL="N" SETINI PROFILE.GAP="" SETINI PROFILE.="1" SETINI PROFILE.PLOTORDER="1"

Tutorial 8: Batch Processing with Scripts 171 GX profile.gx /------------------------------------------------------/ LOG CLOSED : Wed Mar 17 00:56:43 2004 /------------------------------------------------------13. The map script_map.map that was created in Step 2 is displayed showing the

custom base map, line path, and magedited profiles in the colour chosen. 14. Close script_map.map, as we will be re-creating it by running the script. 15. On the GX menu, click Run Script. The system displays the Run a script with

parameters dialog box.

16. Click the [Browse] button and select the Script file you wish to run

(Script_map.gs). Click the [OK] button. The system will begin to process the GS file containing the three GXs you recorded and display the map for you. 17. As an additional exercise, try modifying a parameter in the GS and run it again.

For example, in the editor change the parameter, PROFILE.COLOUR from “B” (blue) to “R” (red). .

172 Tutorial 9: Advanced Mapping and Gridding

Tutorial 9: Advanced Mapping and Gridding As more information becomes available in digital format, earth science specialists are recognizing that it is essential to work with a variety of data from different sources. This approach not only spreads resources as far as possible but it also enables professionals to pool their knowledge and interpret results more effectively and make more informed decisions. In this tutorial, we investigate the integration of geochemical data in to an environment that has focused on a single type of data (i.e. geophysical) only.

Creating a Second Database in a Project We are going to create a second database, in the same project you have open now (GeoDemo.gpf), that contains geochemical data covering the same area as the magnetic data. T O C REATE

A

N EW D ATABASE :


displayed. 2. Specify a New database name (geochem.gdb). Click the [OK] button. 3. The system creates a new database with the database name that you specified and

opens a Spreadsheet window with empty Channel Header and Data cells T O I MPORT D ATA I NTO A S ECOND D ATABASE : 1. On the Database menu, select Import and then click Geosoft XYZ. 2. The system displays the Import XYZ data dialog box.

3. Click the [Browse] button and select the geochem.xyz file located in your

Tutorial directory. Make sure the Import Template box is blank and click the [Template] button. 4. The system displays the Import dialog box with the name of the file you are

importing displayed along the dialog box title bar.

Tutorial 9: Advanced Mapping and Gridding 173

5. Highlight the Z1 channel, and in the Output Channel box change the Name from

Z1 to As. Repeat this procedure with the remaining Z* channels so that the channels have names as shown below.


6. Click the [OK] button to return to the Import XYZ data dialog box. A temporary

import template file (default.i0) is created with the settings you specified. Click the [OK] button to import the data.

7. An Import XYZ progress dialog box will be displayed on the screen while the

system imports the data into the database. The imported data should look like the picture below.


Processing Data in the Spreadsheet The following utilities allow the to apply formulas and perform database operations between channels. In the following example, we will take the Log10 of the As channel and store the results in a new channel called LogAs. T O A PPLY

A

F ORMULA TO

THE

D ATABASE :

1. Select (highlight) the first empty channel header cell, then right click and from the

popup menu, select New. The Create Channel dialog is displayed.

176 Tutorial 9: Advanced Mapping and Gridding 2. Specify the Name for the channel as Log_As and then click the [OK] button. The

system creates a new channel in the database and displays it in the spreadsheet window. 3. Click three times on the Log_As channel header cell to highlight the entire

channel. 4. Press the [=] key from the keyboard to activate the formula bar at the bottom left

hand corner of your screen and type Log10 (As) then press the [Enter] key from the keyboard. 5. The system applies the formula to the channel as shown below.

6. On the Database menu, select Save Database Changes to save your changes. 7. The Save Changes dialog is displayed, click [Yes] to continue.

Plotting Symbols, Colour Bars and Legends Oasis montaj provides the ability to create a variety of symbol type plots of spatially located Earth Science data. This functionality is ideally suited to the presentation of data sets that are not line-oriented, such as geochemical survey results. The types of symbol plots available in the system include:


An effective method for geochemical data is to plot coloured symbols on a map. Oasis montaj enables you to create fixed size coloured symbols or symbols that are sized in proportion to the data values. Colours can be based on a variety of colour files, including zone (*.ZON) , aggregate (*.AGG) , table (*.TBL) or image transform (*.ITR) . Symbols can have different fill and edge colours. The fill and edge colours are independent, so they can be set to different values for different channels. C REATE

A

M AP

1. Select (highlight) the geochem.gdb. 2. On the Map Tools menu, select New map and then select New map from X,Y. 3. The system displays the Data range to map dialog box. Click the [Scan data]

button to have the system query the geochem database for the data ranges and report the Minimum X,Y and Maximum X,Y coordinates. 4. Click the [Next] button. The system displays the Create a New Map dialog box.

Enter a Map name (geochem.map) and from the Map Template dropdown list, select (Portrait A4). 5. Click the [Scale] button. The system automatically chooses a scale that will fit the

data on the map template. Just to round the scale to a more efficient number (e.g. 75000). 6. Click the [Finish] button to open a new blank map. Note:

If no scale is specified, a scale will be chosen which will fit all of the data within the chosen map sheet.

T O P LOT L OCATION P LOT S YMBOLS :

The most basic type of symbol plotting in Oasis montaj is to draw location plot symbols on a map for all data points in the database. 1. Select (highlight) the geochem.map. 2. On the Map Tools menu, select Symbols and then select Location Plot.

178 Tutorial 9: Advanced Mapping and Gridding 3. The system displays the Symbol plot dialog box. Specify the parameters for your

symbols as shown below. Click the [OK] button.

4. The system plots and displays the symbols on your map. T O P OST D ATA V ALUES

ON A

M AP :

Assay data values can be posted next to sample locations on your map. 1. On the Map Tools menu, select Posting. The Post data values on a map dialog is

displayed.


2. Specify the parameters for posting the data as shown above. Click the [OK]

button. The map is redrawn with the As assay values posted. Note: By defining different Posting locations, it is possible to post the values of numerous elements for each sample location (for example, Au, As, Cu, and Pb). T O P LOT P ROPORTIONAL S IZED S YMBOLS : 1. On the Map Tools menu, select Symbols, then select Proportional size. 2. The Proportional size symbols dialog is displayed.

180 Tutorial 9: Advanced Mapping and Gridding 3. Specify the Data channel you wish to process (As), as well as the rest of the

parameters as shown above. The symbol Scale factor value indicates how many data units are represented by a 1mm wide symbol. For example, if you specify that the scale is 1000 then a symbol, which has a data value of 20000, is plotted 20 mm wide. 4. Click the [Symbol] button and the Symbol Attributes dialog is displayed.

5. Select the Symbol as a (circle) and then select (check) the Fill box to enable the

Fill Colour box and select the colour as (red). When you are satisfied with your symbol attributes, click the [OK] button to close the dialog and then click the [OK] button again on the Proportional size symbols dialog to display the symbols on your map. Note: If you specify a base value, the value is subtracted from the data before calculating the symbol sizes. Any negative values that are left after subtracting the base are not plotted.


T O P LOT Z ONE C OLOURED S YMBOLS :

You may wish to create a new map (geochem2.map) at a scale of about 75000 at this point since the map above already has many symbols plotted on it. 1. On the Map Tools menu, select Symbols and then select Zone Coloured. The

Coloured symbols dialog is displayed.


2. Select As as the Data channel and specify the rest of the plotting parameters as

shown above. Click the [OK] button. The system displays the Colour Symbol Tool dialog box.

3. You can select the Log Distribution and if you are satisfied with the colour

distribution click the [OK] button. The system plots the zone coloured symbols on the map.


T O P LOT C OLOUR R ANGE S YMBOLS :E RROR ! B OOKMARK

NOT DEFINED .

The Colour Range Symbols are the most flexible of the entire symbol tools collection. It allows for different ranges of data to be plotted using different symbols, colours and sizes. 1. Create a new map (geochem3.map) at a scale of 75000. 2. On the Map Tools menu, select Symbols and then select Colour Range Symbol. 3.

The system displays the Classified symbol plot dialog box.

184 Tutorial 9: Advanced Mapping and Gridding 4. Specify Au for the Classification channel box and the rest of the parameters as

shown above. Click the [Ranges] button. 5. The system displays the Specify Ranges dialog box.

6. Specify the extent of each range by entering the maximum value for each range as

shown above. Click the [Symbols] button. 7. The system displays the Specify Symbols dialog box.

8. Specify the desired symbol shape for each range. In this example, circles were

chosen for all of the ranges. 9. Click the [OK] button to return to the Specify Ranges dialog box, then click the

[Sizes] button.The system displays the Specify Sizes dialog box.

10. Specify the Symbol Size for each level.

Tutorial 9: Advanced Mapping and Gridding 185 11. Click the [OK] button to return to the Specify Ranges dialog box, then click the

[Colours] button. The system displays the Specify Fill Colours dialog box.

. 12. Choose the colours for the 5 levels and click the [OK] button to return to the

Specify Ranges dialog box. 13. Click the [OK] button to return to the Classified symbol plot dialog box. 14. Click the [Plot] button. The system plots the classified symbols for all 5 ranges

on the map. A close up picture of the range classified gold samples is shown below. The large yellow circles represent those samples that were greater than 100ppm.

This is a very useful tool. As an exercise, try using different symbols to classify the range of the Cu data.

186 Tutorial 9: Advanced Mapping and Gridding T O P LOT L EGEND S YMBOLS :

When you use classified symbols, you will most likely create a legend showing the symbol colours and size ranges used on the map. 1. On the Map Tools menu, select Symbols and then select Colour Range Symbol

Legend. The Classified Symbol Legend dialog will be displayed.

2. Click the [Locate] button. The Locate Legend dialog is displayed. Click the [OK]

button and your mouse will turn into a crosshair. Position the cursor on the map where you want the lower left corner of the legend to be located and click left mouse button. 3. The system redisplays the Classified Symbol Legend dialog box with the X and Y

Positions of where the legend will be located.

4. Specify a Title for Legend Au (ppm) and click the [Plot] button. The system plots

the legend on the map.


Note 1: When you select this option, the system automatically records the colour, symbol and size settings you specified when creating the range classified symbols. This makes generating a legend easy. Note 2: This option is also used for plotting legends for the zoned colour symbols where a (*.ITR) file must be specified. A (*.ITR) file is created when the zoned colour symbols are plotted. The default name is the channel-name.itr, e.g. Au.itr.

Gridding Random Data The random gridding method (RANGRID GX) fits a minimum curvature surface to the data points. For details on minimum curvature gridding, refer to the Help system. T O P ERFORM M INIMUM C URVATURE G RIDDING : 1. Select the geochem.gdb database. 2. On the Grid and Image menu, select Gridding and then select Minimum

curvature. The Minimum Curvature Gridding dialog is displayed.

188 Tutorial 9: Advanced Mapping and Gridding 3. Using the Channel to grid drop down list, select (As) and then specify the Name

of new grid file (As.grd) and a Grid cell size of (50). For more information on the Advance gridding parameters, click the Help ( ) button. 4. Click the [OK] button. The system processes the data and creates the output grid file (As.grd). Note:

5.

Experiment with the data you have generated so far by creating a map displaying the As.grd grid you just created with proportional size symbols displayed as well. This map will allow you to compare two ways of processing your data and the validity of both. The following map shows an example of what such a map would look like.

Gridding Geochemical Data There are four potential methods to use for gridding data:

Tutorial 9: Advanced Mapping and Gridding 189 1. Bi-directional

Suitable for highly sampled data surveyed along regular lines. Can work well with potential field geophysical data. 2. Random

Suitable for randomly oriented data with a relatively large number of samples. Can work well with geochemical data from comprehensive regional and local surveys. 3. Kriging

Suitable for clustered data in which clusters are characterized by a relatively large number of samples and may be widely spaced. Can work well with geochemical data from stream sediment surveys and similarly sampled data. 4. Tinning

Suitable for randomly oriented data with a relatively large number of samples, or clustered data in which clusters are characterized by a relatively large number of samples and may be widely spaced. Can work well with geochemical data. Based on these very general criteria, random gridding and kriging are the optimal methods for statistical data such as that from geochemical surveys. Since geochemical data are statistical in nature and have a high range from sample to sample, it may also be appropriate to reduce the range of data through standard processing (i.e. application of a logarithmic transform). In this brief tutorial, we provide an overview of kriging and describe how to select an initial model (variogram, or more strictly, a semi-variogram) for creating a grid. Selecting a variogram model is the key to obtaining high-quality results – the actual gridding process is relatively routine. We also provide summaries of how to apply kriging in Oasis montaj and create a map of your final results. Kriging – Quick Overview This statistical gridding method uses the method of Kriging to determine a value at each grid node based on the located data you provide. A significant by-product of Kriging is the ability to estimate the error of the data at each grid node. In Kriging, the approach is to first calculate a variogram of the data, which shows the correlation of the data as a function of distance. Simply speaking, the further apart the data points become, the less correlation we expect between points. A variogram shows this phenomena for a given dataset, and based on the variogram, you are able to select a model that best defines the variance of the data. There are five types of variograms you can generate in the system, including: • Power • Sphere • Gaussian • Exponential • -defined


The technique of Kriging uses the model you select to estimate the data values at the nodes of the grid. In geochemical applications, the sphere and gaussian model are typically most effective. The spherical model is mathematically simpler and we typically recommend this model as your starting point. Advanced s may want to experiment with gaussian and -defined variogram models. Geosoft s ordinary Kriging as well as universal Kriging. Universal Kriging differs from ordinary Kriging in that it allows the data to contain a regional trend. For a more in-depth understanding of geostatistical analysis and Kriging, refer to Mining Geostatistics written by A.G. Journel and C.J. Huijbregts, 1978. Importing Data for Kriging For the purpose of this tutorial, we provide a specific dataset called krigsample.csv. This dataset contains clustered data suitable for this method. T O I MPORT S AMPLE D ATA: 1. Create a new database and call it Kriging.gdb. 2. On the Database menu, select Import and then select Geosoft XYZ. The Import

XYZ data dialog is displayed.

3. Using the XYZ data file [Browse] button, locate the krigsample.xyz file. Accept

the default import template and import mode. 4. Click the [OK] button and the system imports the data into the database.


Calculating and Displaying a Variogram Model After importing data, the next step is to calculate a semi-variogram (referred to as a variogram for convenience in Geosoft). The variogram shows the correlation (semivariance) of the data as a function of the distance away from the sampling point. The further apart the data points become the less correlation we expect between points. In this tutorial, we will create a variogram to represent this correlation and then use it to determine the grid values. The normal procedure for creating a variogram is to: • Create a variogram file (*.var) of the channel you wish to display • Select a variogram model • Plot the variogram • Repeat this process for other models. In general, you must specify a geochemical data channel, output variogram file, log option, log minimum and variogram model. In addition, depending on the model you are using, you may have to set additional parameters as follows: Power

Specify a power value to use.

Spherical, Gaussian and Exponential

Specify the Range/Slope, Nugget and Sill.

-defined

Specify an input grid containing your custom variogram model and select the -defined Variogram model.

T O C ALCULATE

A

V ARIOGRAM M ODEL :

In this procedure, we will use the default model (linear) to simply generate a variogram of our data that we can then use to select the optimal variogram model and parameters.

192 Tutorial 9: Advanced Mapping and Gridding 1. On the Grid and Image menu, select Gridding and then select Kriging. The

Kriging dialog is displayed.

2. Complete the entries as shown above and then click the [Advanced>] button. The

Krigging – Advanced options dialog is displayed.

3. In the Name of output variogram file box, specify (Cu). We will leave the

remaining parameters to the defaults. 4. Click the [Variogram Only] button. The system creates a variogram and displays

it in a map in the current project.


In this example, we see a variogram based on the data with a linear model superimposed. The variogram shows the anticipated increase in variability as distance increases. At the right end, it may appear to decrease but this is usually the result of too few pairs for the statistics to be valid. Normally the variogram reaches a point (sill value) at which the semivariance plateaus. The corresponding h value is called the range value – beyond this distance there is no similarity in samples. We also see a plot of sample pairs. This latter plot shows how many sets of samples occur within specified distances of each other – this curve may help you to refine your variogram in the selection of the data points used to visualize your model curve. Here, most of the data occurs within 10 000 m and data beyond this point should not be given as high an emphasis when building your variogram. Selecting Variogram Model and Parameters Selecting a model and parameters is the toughest part of your kriging decision and requires considerable experience. Typically, you would use kriging to grid data within clusters accurately and then truncate the model between clusters so that clusters do not affect the gridding of neighbouring clusters. In this application, data integrity is maintained both within and between clusters and you can examine the error grid to that this effect is maintained. For a spherical model, typically you will have the following values: • Nugget (starting value): The nugget is the average error in each data point, and is indicated by the intersection of the variogram model with the h=0 axis. The default is 0 indicating that there are no repeated samples.


• •

Sill: This is the value corresponding to the point at which the variogram becomes uncorrelated and reaches its plateau point (or goes flat). Range/Slope: The range is the distance at which the variogram model reaches the sill value. Beyond the range, the data is uncorrelated. T O S ELECT

A

V ARIOGRAM M ODEL :

1. After displaying the starting linear model, evaluate the data and that the

spherical model is appropriate. 2. On the Grid and Image menu, select Gridding and then select Kriging. 3. The system displays the Kriging dialog box, click the [Advanced>] button and

specify the following settings on the dialog: • Select spherical for the Variogram model. • Specify a different Name of the output variogram file such as Cu_spherical.VAR. • Specify the Range/Slope value from inspection of the variogram and pairs graphs (4000) • Specify the Nugget value from inspection of the variogram and pairs graphs (0.06) • Specify the Sill value from inspection of the variogram and pairs graphs (0.16) 4. Click the [Variogram Only] button. The Cu_spherical_variogram.VAR is plotted and displayed in your current project.

5. You are now ready to grid the data using the model.

Tutorial 9: Advanced Mapping and Gridding 195 T O G RID

THE

D ATA:

1. On the Grid and Image menu, select Gridding and then select Kriging. The

Kriging dialog is displayed.

2. Select the Cu Channel to grid and the Name of new grid file as Cu.grd. Click the

[Advanced>] button to display the Kriging – Advanced Options dialog.

3. The system displays the Kriging dialog box. Specify the information as shown

above and click the [
current project.


Plotting Krigrid Data As an exercise, try displaying your krigrid grid. The basic steps are as follows: 1. Create a new map 2. Display the grid 3. Display the variogram (using the Grid/Gridding/Plot Variogram menu option) 4. Display sample locations 5. Draw the Base map

Your completed map containing the Krigrid data should look something like this:

Tutorial 10: Advanced Imaging 197

Tutorial 10: Advanced Imaging It is often helpful for interpretation to combine multiple types of data together using special colour schemes. Two common methods of combining grid images are: • Using a grey-shade for one type of data, and full colour for another (for example, grey shaded topography with colour magnetics). • Using a ternary diagram presentation – three data grids using either a cyanmagenta-yellow (CMY) or red-green-blue (RGB) colour model (commonly used with airborne radiometric data). As we have seen previously, it is possible to create maps and add images to them, including single colour grid images, colour-shaded grid images, and JPG files. In addition, the system also s a variety of advanced options that you can access via the Grid|Display Grid. Following are examples: G REY S HADED M AGNETICS

WITH

C OLOUR A U :

1. Open the geochem.gdb database and the tfmag.map map. (Note: if your

tfmag.map does not have all these groups (path, profile etc.) you will not need to hide them. However, if your tfmag.map does not have a base map add this now.) 2. Click the View/Group Manager button (

) and hide all Data groups except the

coordinates group.

. 3. On the Grid and Image menu, click Display grid and then click 2-grid composite. 4. The system displays the Display 2.grid composite on map dialog box. Specify the

parameters for the dialog box as shown below (if you do not already have an As.grd file, create one using minimum curvature gridding).

198 Tutorial 10: Advanced Imaging

5. Click the [Current Map] button. This procedure loads the grey-shaded image of

the total field magnetics, plus a colour image of the gold channel, As. The map appears as follows:

3-G RID T ERNARY P LOT : 1. Before you begin this tutorial, you must have grid files, (*.grd) for the Au, Cu

and Pb channels from the geochem.gdb database. If you have not already gridded this data please do so now using the minimum curvature gridding method.

Tutorial 10: Advanced Imaging 199 2. Open the geochem.gdb database and the tfmag.map map. Click the View/Group

Manager button (

) and hide all data groups except the coordinates group

3. On the Grid and Image menu, click Display grid and then click Ternary image. 4. The Ternary colour image dialog is displayed. Enter the parameters for this

dialog as shown below.

5. Click the [Current Map] button. The system processes and displays the ternary

image of the Pb-Au-Cu grids, using Red-Cyan for Pb, Green-Magenta for Au, and Blue-Yellow for Cu.

6. On the Grid and Image menu, click Display grid and then click Ternary legend.

200 Tutorial 10: Advanced Imaging 7. The system displays the Ternary Colour Legend dialog box. Enter the parameters

as shown below and click the [OK] button.

8. The system displays the Locate Legend dialog box. Click the [OK] button and

locate an area on the map to display the legend

9. The system creates and displays the ternary legend on you map.

Tutorial 11: Coordinate Systems 201

Tutorial 11: Coordinate Systems Oasis montaj features "smart projections" that reprojects data "on-the-fly" as it is displayed. This functionality enables maps to have several views; each containing a different set of projected coordinates. In addition, dynamic links between maps and data are maintained, even if different coordinate systems are used.

What is a Map Coordinate System? A map coordinate system is a systematic construction of features on a plane surface (a map) that represents corresponding features on a spherical (or curved) surface (the earth). Coordinate systems include actual objects (highways, coastlines) as well as constructs (meridians, political boundaries). For more information on coordinate systems see the Appendix: Understanding Spheroids and Datums page 269. Parts of a map Coordinate System Understanding how coordinate systems work requires a basic knowledge of the different components. When working with coordinate systems, you should be familiar with some . The below represent different components of a coordinate system: • Ellipsoid: A solid figure (shaped like an egg or oval) for which every vertical cross-section is an ellipse. • Spheroid: A spheroid is an oblate ellipsoid of revolution (basically an ellipsoid) that is used to model the surface of the earth for the purpose of making maps. • Datum: A reference value to which other measurements are referred. Also, an arbitrary reference level to which measurements are corrected. For example, a datum for elevation would be sea level. • Local Datum Transform: A datum adjusted for use in a specific location on the earth. Earth centre offset, rotation, scale factor relative to the WGS84 datum. • Projection Method: The mathematical algorithm used to transform points on a spheroid to their relative locations on a flat surface (i.e. Transverse Mercator, Lambert Conformal).

202 Tutorial 11: Coordinate Systems

Understand Geosoft Coordinate Systems When dealing with map coordinate systems, it is important to be aware that the geographic map location (X,Y) of any objects are either an implied or a known map coordinate system. If you do nothing to define map coordinate systems in your data, Oasis montaj will assume that all locations (X,Y) are in the same map coordinate system, which is unknown. However, you must define map coordinate systems if you want to: • Annotate maps with longitude, latitude locations. • Convert the location of information (data or grids) from one map coordinate system to another. • Display information on a map that is in a different map coordinate system. • Defined a warped coordinate system to fit data to a desired map coordinate system. Note: If you do not need to do any of these things, you do not have to deal with map projections. For more information on projections see the Appendix: Understanding Spheroids and Datums page 269. In Oasis montaj, working with map coordinate systems requires that the map coordinate system information be attached to coordinate information of a database, grid or map. Once you have attached a map coordinate system to a set of coordinates, Oasis montaj will deal with any re-projections that may be required to properly display data together on maps. Map coordinate systems can be defined for any pair of channels in a database, for a grid coordinate system, and for a data view in a map. In most cases, all that is required is to define the map coordinate system of the "X" and "Y" channels of an original database. This map coordinate system will then be ed on to grids when data is gridded, and map views will inherit this coordinate system when they are created. Map coordinate systems of data channels, grids and views can also be viewed and modified at any time, although the modification of map coordinate systems does require specific and accurate knowledge of the projection information.

Define a Coordinate System in Oasis montaj In Oasis montaj a coordinate system is always attached or applied to something. This can be a coordinate pair on a database, a grid, or a map view. Before you can apply a coordinate system, you will need to know the following information about your data. The type of projection coordinates that contain the location information for your data: For more information on coordinate systems see the Appendix: Understanding Spheroids and Datums page 269. • Projected (x,y) The coordinates are in a known projected coordinate system, such as UTM, or some other map-based coordinate system. • Geographic (long,lat) The coordinates are longitudes and latitudes in degrees. Only a datum is required. • The coordinate subset to use (e.g. UTM, USA State Plane).


The units of measurement you want to use (e.g. feet, metres). • The Datum (or ellipsoid) to use (i.e. WGS 84 / UTM zone 44N) and local datum to use. Important Note: When you define (or modify) a coordinate system the coordinates of the data (database, grid or map view) remain unchanged. This process only sets the “coordinate system label”. However, when you reproject data into another coordinate system the numerical representation of the coordinates will change. •

Define X, Y channels Once your data has been successfully imported into Oasis montaj you can set the coordinate system and projection information for your database. One of the first steps in setting a coordinate system is defining your X and Y channels. (This can be done during the import process, or will be automatically set if your coordinate channels are called X and Y by default.) Note that, you cannot create a map until your X and Y channels are defined. In Oasis montaj we have introduced "current" X and Y (and Z) channels. This feature enables s to select the channels that they would like to use as the current X and Y (and Z) channels (for example, East, North, and Relative Level). Markers have been added to the channel header to indicate which channels are currently defined to be the "current" X, Y (and Z) channels. The markers are little rectangles on the right side of the header cell, and contain "x", "y" (or "z") in reversed display (like the triangle protection symbol on the left). When you alter the current coordinate channels, these markers change too. Normally, s will just get "x" and "y", but if you have a "Z" channel it will get the "z". The "z" will be used in Wholeplot databases, where DH_EAST = "x", DH_NORTH = "y" and DH_RL = "z". Note:

All grids, maps, and databases derived from a database that has coordinate system information attached to it, will also include the coordinate system information. T O D EFINE X

AND

Y

CHANNELS :

1. When you first import your data, your X and Y coordinate channels may be called

East and North (or any other valid naming system). 2. To define X and Y channels select the Coordinates/Set Current X, Y, Z,

Coordinates menu item. The Set current X, Y channels dialog box is displayed.


3. Select your X and Y channels (in this example, you would select the East and

North channels) from the database, and click [OK]. 4. Your database now has set X and Y channels (titled East and North) which can be

seen by the inverse x and y on the right side of the channel header cell.

Set a Coordinate System to a Coordinate Pair in a Database The Oasis montaj Coordinate System interface has been redesigned to make creating, editing or viewing coordinate systems a simple, one-step process. Oasis montaj uses a single dialog to set and modify coordinate system settings. The Coordinate System tool also now s ESRI projection files (PRJ). B EFORE

YOU BEGIN …

To define a coordinate system, you must know the type of coordinate system that is used for the data. If the wrong coordinate system type is specified, Oasis montaj may return strange results or take an unusually long time to process the data. A coordinate system can be defined from any pair of channels in a database. These two channels must contain coordinate information. Normally, the X and Y coordinate channels are used. s can define coordinate system from any of the following sources: a. Projected (x,y) b. Geographic (long,lat) c. No Projection d. Copy from channel e. Copy from a grid f. Geosoft PRJ file (projection file) g. ESRI projection files (PRJ). h. Geosoft warp file


Setting a Projected (x,y) coordinate system to a database You would use the Projected (x,y) coordinate system if your database coordinates are in a known projected coordinate system, such as UTM, or some other map-based coordinate system. T O S ET

A

P ROJECTED (X, Y) C OORDINATE

SYSTEM FOR

D ATABASE C HANNELS :

1. Open a Database (geochem.gdb) that contains at least two channels with

coordinate information (X, Y). 2. On the Coordinates menu, click Set Projection. The Georeference database

channels dialog is displayed.

3. Select the X and Y coordinate channels that you will use to set the coordinate

system, and select Set as current X,Y? as Yes, then click the [Projection] button. The Coordinate System dialog is displayed. This dialog displays the current coordinate system information for the database. If the database contains no coordinate system information, the Unknown radio button is selected in the Coordinate System section of the dialog.


Whenever you work with coordinate systems in Oasis montaj, the coordinate system information for the current database, grid, or view is displayed in this dialog. When the fields in the dialog are shaded grey, you can only view the information. If the dialog box fields are white, you may edit the values. 4. In the Coordinate System section of the dialog, select the coordinate reference system for the data. For example, if the data in your database is organized by X and Y locations, you would choose the Projected (x,y) option, however if the data in your database is organized by latitude, longitude locations, you would choose Geographic (long,lat). For more information on setting a Geographic (lat, long) coordinate system see the following topic; To set a Geographic (long,lat) Coordinate System for a Database page 211. Note:

5. The Coordinate System section also includes a [Copy from] button that displays

the Copy Coordinate System From dialog.

Tutorial 11: Coordinate Systems 207 6. Use this dialog to copy a coordinate system from another file. The file types

ed include, Database, Grid, Geosoft Voxel, Geosoft projection (*.prj), ESRI projection (*.prj), Geosoft warp (*.wrp), Geosoft polygon (*.ply) and GMSYS model. 7. In our case, as our data is organized by X, Y locations we will select the

(Projected (x,y)) radio button to set the coordinate system reference system. The appropriate dialog parameters will become enabled.

8. Using the dropdown lists you can select the Datum, Local datum transform and

Projection method. Note that, the Local datum transform dropdown list provides all the local datum transforms, which apply to the selected Datum. 9. For our tutorial data, select the following coordinate system parameters:

Datum: NAD 27 Local datum transform: [NAD 27] (8m) Cnaada (Northwest Territories; Nunavut; Saskatchewan Coordinate System: Alaska CS27 zone 7 Note:

If the coordinate system method you want to use does not exist, but you know the parameters for it, you can click the Projection method dropdown menu ( ), which along with displaying the Projection method information includes a [New] button that displayes the New Projection Method dialog.


Use this dialog to create a new (custom) coordinate system method. 10. Your Coordiante System dialog should now look like the following:

Tutorial 11: Coordinate Systems 209 11. You will note that the Length units have been set to match the units used by the

coordinate system, in our case (US survey foot) and should not usually be changed. 12. You can use the dropdown menus (

) to display the detailed information for each of the coordinate system parameters, as shown below:


13. If all the coordinate system settings are correct, click [OK] to apply the

coordinate system.


Setting a Geographic (long, lat) coordinate system to a database You would use a Geographic (long, lat) coordinate system if your database coordinates are in longitudes and latitudes degrees and only a datum is required. Important Note: When you select a “Geographic (long,lat)” coordinate system the geographic coordinates will be displayed as a Cartesian system with units of degrees. This means that you will not be able to display latitude and longitude annotations in the base map because the X, Y coordinate system of the map will be represented by the long, lat coordinates. TO

SET A

G EOGRAPHIC (L ONG , L AT ) C OORDINATE

SYSTEM FOR A

D ATABASE :

1. Open a Database that contains at least two channels with geographic coordinate

information (long, lat). For example, create a new database (projtest.gdb) and then import the XYZ data (projtest.xyz). Using the Edit Channel dialog rename the East and North channels to Longitude and Latitude, ing to specify the display Format as (Geographic), as shown below:

If your Longitude, Latitude channels display double astricks (**), that only indicates that the channels are too narrow to display the data. Widen the channels and the data will be properly displayed. 2. On the Coordinates menu, click Set Projection. The system displays the Georeference database channels dialog box.

Note:


3. Select the X and Y coordinate channels that you will use to set the coordinate

system (Note that, in this case the selected X, Y coordinate pair are called Longitude and Latitude) and then click the [Projection] button. The Coordinate System dialog is displayed.

Whenever you work with coordinate systems in Oasis montaj, the coordinate system information for the current database, grid, or view is displayed in a dialog box similar to the one above. When the fields in any dialog box are shaded grey, you can only view the information. If the dialog box fields are white, you may edit the values. 4. Using the Coordinate system radio buttons, select the coordinate reference system for the data. For example, if the data in your database is organized by latitude and longitude locations, you would choose the Geographic (long,lat) option, however if the data in your database is organized by X, Y, you would choose Projected (x,y). For more information on setting a Projected (x, y) coordinate Note:


system see the topic; To set a Projected (x, y) Coordinate system for a Database page 205. 5. In this case, as our data is organized by Longitude, Latitude locations and we will

select the (Geographic (long,lat)) radio button to set the coordinate system reference system. The appropriate dialog parameters will become enabled.

6. Using the dropdown lists you can select the Datum and Local datum transform.

Note that, the Local datum transform dropdown list provides all the local datum transforms, which apply to the selected Datum. 7. For our tutorial data, select the following coordinate system parameters:

Datum: NAD 27 Local datum transform: [NAD 27] (8m) Cnaada (Northwest Territories; Nunavut; Saskatchewan 8. Your Coordiante System dialog should now look like the following:


9. You will note that the Length units have been set to match the units used by the

coordinate system, in our case (degree POSC) and can not be changed. 10. You can use the dropdown menus (




coordinate system.

Define the map coordinate system of a grid When you create a grid from a database that already has location (coordinate) channels with a defined coordinate system, the coordinate system information in the database is automatically applied to the grid. Note: To ensure consistency between your databases and grids it is good practice to define a coordinate system in your database before creating grids from it. T O M ODIFY

OR

D EFINE

THE

M AP C OORDINATE

SYSTEM OF A

G RID :

1. On the Grid and Image menu, select Properties. The Grid Properties dialog is

displayed.


2. Using the Browse (

) button, locate the grid you want to modify. Click the [Next>] button to display the Grid Properties dialog. This dialog reports all of the basic information about the selected grid.

3. Click the [Modify] button to display the Modify Grid Properties dialog. This

dialog displays the information that is used to locate the grid in a real coordinate system. Note that, changing anything in this dialog will have the effect of moving or changing the apparent size of the grid when displayed on a map.


4. Click the [CoordSys] button to modify (or define) the map coordinate system of

the grid file. 5. The Coordiante System dialog is displayed. This dialog displays the current

coordinate system information for the grid. As this grid has no coordinate system information set, the Unknown radio button is selected.

6. Whenever you work with coordinate systems in Oasis montaj, the coordinate

system information for the current database, grid, or view is displayed in this


dialog box. When the fields in any dialog box are shaded grey, you can only view the information. If the dialog box fields are white, you may edit the values. 7. Using the Coordinate system radio buttons, select the coordinate reference system

for the data. In this case, as the data in our grid is organized by Longitude, Latitude locations we will select the (Geographic (long,lat)) radio button to set the coordinate system reference system. The appropriate dialog parameters will become enabled.

8. Using the dropdown lists you can select the Datum and Local datum transform.

Note that, the Local datum transform dropdown list provides all the local datum transforms, which apply to the selected Datum. 9. For our tutorial data, select the following coordinate system parameters:

Datum: NAD 27 Local datum transform: [NAD 27] (8m) Cnaada (Northwest Territories; Nunavut; Saskatchewan 10. Your Coordiante System dialog should look like the dialog above. 11. . You will note that the Length units have been set to match the units used by the

coordinate system, in our case (degree POSC) and can not be changed. 12. You can use the dropdown menus (



13. If all the coordinate system settings are correct, click [OK] and the Modify Grid

Properties dialog will again be displayed. Click the [OK] button to apply the changes to the grid file and the Grid Properties dialog will be displayed. Click the [Exit] button to close the dialog.

Defining the map coordinate system of a map view In Oasis montaj maps have several views that contain information about the map. Coordinate system information for a map is contained in a data view. Base map information is contained in the base map view. There are two choices available when you create a new map, from X, Y or from latitude-longitude coordinates. When you create a new map the system either reads the manually entered coordinates, or scans a ’s specified database or grid file and attaches their coordinate system and coordinate attributes to the specified map view.

220 Tutorial 11: Coordinate Systems Note:

The projected base map created from a latitude-longitude range will be windowed based on lines of latitude and longitude, not X and Y, and the data window will be oriented so that North is up at the centre of the map.

Create a new map from X, Y coordinates Use the New map from x,y menu item to create a new blank map to fit the data range specified. The data range can be entered manually, or it can be determined from the range of selected data in a database or from a grid range. T O D EFINE

A

M AP C OORDINATE

SYSTEM FOR A

N EW M AP

FROM

X,Y

1. The first step is to create a new map using the coordinate system from an existing

database or grid. On the Map Tools menu, select New Map|New map from x,y. The Data range to map dialog will be displayed.

2. This dialog shows the data range (coordinate), units and coordinate system

information from the last coordinate system that was used. To change the coordinate system information, you will need to scan an existing database or grid for the coordinate system information. To scan a database for the data range and coordinate system information: a. Click the [Scan Data] button. b. The system will scan the current database open in your project. c. The system will re-display the Data Range to Map dialog box showing the new data range, and coordinate system information obtained from the database. To scan a grid for the data range and coordinate system information: a. Click the [Scan Grid] button. b. The system will prompt you to specify a grid file that contains coordinate system information. c. Select a grid file, and click [OK].


d. The system will display the Data Range to Map dialog box showing the new data range, and coordinate system information obtained from the grid. 3. Click the [Projection] button to view the coordinate system information. The

Coordinate System dialog is displayed. This dialog will display the known coordinate system information as defined in the scanned database or grid file. The example below shows the coordinate system information for a map containing no coordinate system information.

Whenever you work with coordinate systems in Oasis montaj, the coordinate system information for the current database, grid, or view is displayed in the Coordinate System dialog. When the fields in any dialog box are shaded grey, you can only view the information. If the dialog box fields are white, you may edit the values. 4. For information on defining a coordinate system using the Coordinate System dialog go to Step 4 of the Setting a Projected (x,y) Coordinate System on page 205. Note:

5. Once the coordinate system has been defined, the Coordinates System dialog will

display the coordinate system information. Note to display the Datum, Local datum transform and Projection method details, as shown below, click the dropdown menus (

).



coordinate system and the Data range to map dialog will again be displayed.


7. Click the [Next>] button to continue. The Create a New Map dialog box will be

displayed.

8. Specify a Map name for the new map. You can also select a Map template to use

for your map layout. To automatically calculate the map scale, click the [Scale] button. 9. The default scale that will fit the defined data range to the specified template will

be displayed. You can modify this value to a more appropriate scale (e.g. 60000). 10. Click the [Finish] button when you are done. The system will create a new

(blank) map with coordinate system information in the Data View. New map from Latitude – Longitude coordinates To create a new map from Latitude-Longitude requires a database that has a Projected (x,y) coordinate system. When using latitude-longitude degrees as the coordinates of your data and/or a geographic coordinate system you need to use New map from x,y menu item The resulting map will have latitude and longitude displayed in a right angled Cartesian coordinate system. Note that, with a Projected (x,y) coordinate system, you can display Latitude and Longitude annotations on the basemap of a new map created from x,y coordinates.

224 Tutorial 11: Coordinate Systems T O D EFINE

A

M AP C OORDINATE

SYSTEM FOR A

N EW M AP

FROM LAT / LONG :

1. The first step is to create a new map using the coordinate system from an existing

database or grid. On the Map Tools menu, select New Map|New map from lat,long. The Data range to map dialog will be displayed.

2. This dialog shows the data range (coordinates), units, and coordinate system

information from the current (selected) database in your project. To change the coordinate system information, click the [Projection] button and the Coordinate System dialog will be displayed. To scan a database for the data range and coordinate system information: a. Click the [Scan Data] button. b. The system will scan the current database open in your project. c. The system will re-display the Data Range to Map dialog box showing the new data range, coordinate information and coordinate system information obtained from the database. To scan a grid for the data range and coordinate system information: a. Click the [Scan Grid] button. b. The system will prompt you to specify a grid file that contains coordinate system information. c. Select a grid file, and click [OK]. d. The system will display the Data Range to Map dialog box showing the new data range, coordinate information and coordinate system information obtained from the grid. Note: After creating a map from Longitude/Latitude the data view of the new map will have a warp attached to it. This is because when we create a Longitude/Latitude map we warp the view so that North is at the top and centred. If you remove the warp on your map, new elements may not be positioned correctly.


Displaying data with different Coordinate Systems on a map Since grids, images, data and maps can have different coordinate system information, you may want to display one or more types of coordinate systems on a map. The following is a list of data types that you can attach coordinate system information to and place on a map: • • • • • • •

A grid or image Located data ArcGIS LYR ArcView SHP MapInfo data Vector files such as DXFs etc

When displaying different coordinate systems on a map: 1. Identify the coordinate system for each data type (i.e. grids, images, maps, or located data). Data types with different coordinate systems can be placed on the same map. However, make sure the data cover the same geographical area. 2. Data that is imported into a map is re-projected into the map coordinate system when it is displayed. For example, if you place a grid with latitude/longitude coordinate system coordinates on a map defined in UTM coordinates, the system will display the grid on the map in the map’s coordinate system while preserving the grid’s coordinate system information. In this example, the lat/long meridians on the grid would appear curved, while the UTM meridians would appear straight.

Applying a warp to a grid Warping is useful when you have an un-referenced grid file in an unknown coordinate system or an un-referenced image. •

To relocate data, define one control point.

•

To scale and rotate data, define two points.

•

To scale in X and Y and rotate, define 3 control points.

•

To perform a quadrilateral warp, define 4 control points.

T O D EFINE

A

W ARP :

1. On the Coordinates menu, select Georeferencing|Define a Warp. The Warp file

Creation dialog is displayed.


2. Specify an Output Warp file name (.wrp) and from the dropdown lists select the

Warp type and Definition Mode. Note that, the 4-point warp requires the points are in a clockwise order. The multi-point warp (more than 4 points) is best for small translations relative to the units of distance on the map. Note: The Semi interactive mode is a good method, it enables you to select the points on the map that you are warping from (for example, the corners of a bitmap) and then manually input the points (in UTMs) that you are translating to. If you find that you cannot accurately select these points, try the other modes (interactive and manual) to enter the four points. , that you can use the right mouse menu to zoom, shrink, and pan around the map while you are selecting the points. 3. Click the [OK] button. The Map projection dialog is displayed, asking if you want to “Define the output coordinate system”.

4. At this stage, you can define the coordinate system of the map, for the purposes of

this tutorial, we will click [No] button to continue applying the warp. The Define Warp control points dialog is displayed.

5. This dialog tells you to click on the point location for each point in your warp file,

and then specify the new “warped” location in the following dialog. Click the [OK] button to continue.


6. The cursor will change to a crosshair (

) enabling you to locate the first point. Once you have located the first point, the Assign new coordinate 1 of 4 dialog(s) will be displayed.

7. Specify the New X Y coordinates and click the [Next>] button to specify the next

coordinate point location. Continue this until you have specified the 4 coordinates. Note: Temporary circles will be placed on the locations that you select with the crosshair cursor. These circles will be removed once all of the control points have been set and the warp control file has been created. 8. To apply the warp to the grid, on the Coordinates menu, select Georeferencing|Warp a grid. The Warp a grid dialog is displayed.

9. Using the dropdown list, select the Grid file to warp. Using the Browse () button,

locate the Warp definition file (.wrp) from your project directory and then specify a New warped grid file. Click the [Next>] button to continue. The New warped grid dialog is displayed.


10. If all of the parameters are correct, click the [Finish] button to warp the specified

grid file. Warping image files If you want to warp an image file (i.e. tiff, bmp) and the file is large, you may only want to attach the warp to the file. "Attaching" the warp is suitable if you have a very large file that is stored on a CD, for instance. The warp process is repeated every time you display the file to a projected map but the original file remains unchanged. When you warp an image, the warped output image must be a Geosoft COLOR grid (*.grd) File type in order to keep the colours of the original image. If the image of the new warped grid appears twisted or is an incorrect size, check the warp points are in a circular order and the points are correctly located within the defined map area. Converting Elevations The Geoid height menu option enables you to convert GPS elevations to elevations relative to the geoid. Geoid height (GEOID GX) will create a channel of the geoid height relative to the GRS 80 spheroid for a given pair of coordinate channels. This GX requires a grid of the geoid model, which is the elevation of the geoid in metres relative to the GRS 80 spheroid, which is found in the Oasis montaj/etc directory. For more information, see the GEOID GX help topic.



Coordinate system concepts and FAQs A "Datum" defines the earth model used to represent the "Geoid", which is effectively the surface that would be defined by the sea level throughout an area being mapped. At this point, we should all understand that the "geoid" undulates according to the gravitational field; hence, it cannot be defined perfectly by a simple mathematical expression. The business of cartography is to map features that exist on a local geoid to a flat piece of paper. Q 1.) How do we get from a geoid to a map? A 1.) The first step is the "datum". The datum consists of an ellipsoid, a prime meridian, and a specific part of the earth for which the datum applies. The datum ellipsoid is a perfect mathematical surface that best approximates the shape of the earth over the area of a datum. Latitude, longitude locations on a datum is the closest match of the geoid location to the datum ellipsoid surface. For example, latitude, longitude coordinates on the NAD27 datum use the Clarke 1866 ellipsoid with Greenwich as the prime meridian. One should note that the mapping of the geoid shape to the ellipsoid is not perfect because of the afore-mentioned imperfections in the geoid. At this point, it is worth pointing out that many datums share the same ellipsoid. The difference between them is that a specific datum only applies to a specific area of the earth, and the geoid of that area is implied by the datum name. For example, "Luzon 1911", "Mound Dillon" and "NAD27" are all datums based on the "Clarke 1866" ellipsoid, but are used to map the geoid from the Philippines, the island of Tobago, and the North (and central) America respectively. Once we have a longitude, latitude on a specific datum, it is the job of a map coordinate system to convert the latitude, longitude of the round earth to a Cartesian X,Y coordinate for a flat piece of paper. The next piece of the puzzle is to understand why we need a refinement of the datum into what Geosoft calls "local datums". The advent of GPS and satellite mapping required the definition of a single datum that best approximates the entire earth. After a bit of evolution, we have settled on WGS 84, which is truly a "perfect" datum that represents an exact ellipsoid, and the centre of that ellipsoid is at the gravitational centre of the earth. A fundamental problem in modern cartography is how to convert a latitude, longitude on the WGS 84 datum to, say, NAD27 so that a location can be used on NAD27 maps, or vice versa. Because datums like NAD27 represent a geoid, and WGS represents a perfect ellipsoid, we need a way to convert the imperfect geoid shape of NAD27 to the perfect WGS27. The best way to do this is to measure the difference between known latitude, longitude locations on the NAD27 datum and the WGS84 location that one receives from a GPS measurement. This has been done throughout Canada to produce the NTv2 model of NAD27, and throughout the United States to produce the NADCON model. This process is also being carried out at continental scale in other parts of the world. Both NTv2 and NADCON are implemented as gridded corrections


models, that given a location, one can look up the correction (both are ed in Geosoft). A second way to make the correction is to force the surface of the WGS 84 ellipsoid to lie as closely as possible to the surface of the datum ellipsoid (which in turn approximates the geoid), such that a simple mathematical conversion is within acceptable accuracy. This can be done by adjusting the location of the centre of the earth of the datum ellipsoid relative to WGS84, which is the basis of the Molodenski and Bursa Wolf corrections (parameters are in datumtrf.csv). However, such simple conversions are only accurate over a relatively small part of the datum, depending, of course, on the complexity of the geoid of that datum. For datums that cover a large region, such as NAD27, one needs many different adjustments depending on which part of the NAD27 datum you are on. For example, the very large area approximations such as "MEAN Canada" are much less accurate in the Yukon than "Canada (Yukon)". Both are less accurate than the NTv2 correction lookup. Q 2.) When I buy a topographic map of Canada (of say B.C.) it says it uses the NAD27 ellipsoid. It doesn't say what local transformation it uses? A 2.) First, NAD27 is a datum, not an ellipsoid, and the NAD27 datum uses the Clarke 1866 ellipsoid. You must choose which local datum transform is most appropriate for your needs. We would recommend always selecting the local transform that is most specific to your area, in this case "[NAD27] Canada Alberta; British Columbia". You could also choose "[NAD27] Canada NTv2 (20 min)" if the highest accuracy is required, but this is slower and more demanding of system resources. In our "Datum" list, we also include the names of all the common earth ellipsoids (with a "*" prefix). This is because practitioners have commonly confused ellipsoids with datums, and one often only knows the ellipsoid. By including the ellipsoid names in the list, we make life a bit easier for you when you receive a map and the information that it is "Clarke 1850, UTM 42S". However, if you need to do a local datum transform, you must determine (or guess) at the real datum name, which is also why we list the local transforms by area of use. Q 3.) I found where the ldatum.csv file calls the datum for say [NAD 27] Canada (Ont.&Man.) but couldn't find the call to the appropriate datum for [NAD27] Canada (BC/AB). Did I just not look hard enough? A 3.) Yes, these transforms are in the tables. When maintaining the tables, we load the tables into Excel and use the Data/Sort function to sort by datum or area of use (or any column) to help find things. The ldatum.csv file is used only by the coordinate system wizard to provide a list of the available coordinate systems by datum and by area of use. This file refers to the actual local datum transform name and parameters in “datumtrf.csv”. Note that, the tables are only used to construct the coordinate system information the first time something requires a coordinate system. Once constructed, the parameters become part of the object in question, and changing the tables later has no effect.


You can find more information on how the tables are constructed and related in the Coordinate System help.

Tutorial 12: Database Maintenance Utilities 233

Tutorial 12: Database Maintenance Utilities There are a number of utilities available for data maintenance. These are available to allow the to check the status of the database, generally in a troubleshooting or preventative maintenance role. The following is a list of the data maintenance utilities: • Database details • database • Defragment database • Grow database • Repair database

Checking Database Details From time-to-time, you may want to examine the database details. T O C HECK D ETAILS

OF A

D ATABASE :

1. Select the geochem.gdb database. 2. On the Data menu, click Maintenance and then click Details. 3. The system displays the About Database dialog box.

4. We are mostly concerned with whether we are close to exceeding the limits of our

Elements (Groups or Lines, Channels, Blobs, Block Size, Compression and File

234 Tutorial 12: Database Maintenance Utilities

Size). Another area of concern is what the Statistics show us. Statistics let us know at a glance how large the GDB is and whether the space is being used efficiently. If the Unused or lost space seemed excessive (say greater than 20%) we might consider Defragmenting the database (to follow). For more information about these statistics please refer to the Help System. 5. Click the [OK] button to close.

Defragmenting the Database As you work with data in the database, new and modified data are saved to the end of the database file and to space freed within the database before the last time you saved the project. As the database grows you can lose space due to fragmentation or from simply erasing data. T O D EFRAGMENT Y OUR D ATABASE 1. Make sure you have backed-up the database before packing. 2. On the Data menu, click Maintenance and then click Defragment. The system

removes all unused space by repacking the data as efficiently as possible and reduces the database file (*.GDB) size by the amount of freed space.

Growing, ing or Repairing your Database: If you find that the original size limits that were selected for your database (lines/groups and channels/fields), were too small, you can increase these limits using the Grow command. If you wish to check the integrity of your database, you use the command. If your database has been corrupted (for example, if the computer failed during a Defragment operation) you can run the Repair utility to try to recover some or all of the data. For each of these three commands, please refer to the detailed explanations in the Online Help System.

Adding Database Comments Comments about your data can be added to the comment block of a database. Comments are useful as a place to hold information about the data collection procedures, instrumentation and surveyors used, any specific problems and the solutions to them, and other bits of information that may have formerly been kept as field notes, ree files, or other notes. The comment block is an RTF file that can be edited with the Windows Wordpad application, or another text editor. T O A DD C OMMENTS

TO

Y OUR D ATABASE :

1. On the Data menu, click Database comments. This launches your editor and

opens the file _dbcmnt.RTF which is stored in your database. Edit this file however you wish, adding text, pictures, etc. When you are done editing, close the editor. You will be prompted to save the file. Click the [Yes] button.

Tutorial 12: Database Maintenance Utilities 235 2. On the Data menu, click Database comments again. You will see the comments

that you entered at Step 1.

Tutorial 13: Exporting and Printing Maps 237

Tutorial 13: Exporting and Printing Maps The Oasis montaj Mapping and Processing System provides the ability to export interim processed data to another systems for additional manipulation or to a GIS system for creating final map products and integrating with other sources of data. Required tools for exporting data to Geosoft XYZ and other formats are also provided. Oasis montaj uses your installed Windows system drivers to create printer or plotter output. Depending on your installed driver, you may find it does not produce the highest quality output or that it takes a long time to produce a plot. Geosoft provides a special printer configuration capability that enables you to initalize an internal raster engine that performs most of the print/plot processing and es it to the driver for final output. If you are not satisfied with your driver's performance, you can try selecting this option. Normally, with high-quality drivers, you should not have to use this option but it can help with problem drivers or PostScript printing.

Exporting Maps to a File Geosoft recognizes the need for the ability to move data, grids and images easily to other software systems. ed export formats for maps include: Enhanced Metafile ArcView Shapefile CGM Plot Bitmap PCX PNG Encapsulated Post Script TIFF Compressed Geosoft COLOUR Grid ER Mapper RGB ER Mapper ECW Compressor

MapInfo TAB Geosoft Plot file DXF AutoCAD DXF AutoCAD v12 JPEG JPEG High Quality TIFF GeoTIFF MapInfo TIFF ArcView TIFF

For more information on exporting data, refer to the Exporting and Archiving topic in the Oasis montaj Online Help system. T O E XPORT M APS

TO A

F ILE :

1. Select an open map in your project. 2. On the Map menu, click Export. The Export Map dialog is displayed.

238 Tutorial 13: Exporting and Printing Maps

3. Specify the Region to Export (Viewed Region, Full Map or Selection). 4. Select the Output Format, the Image Resolution and where to Export the map to

(File or Clipboard). 5. Using the Options dropsown list, select (Cluster Dither, Error Diffusion or No

Dither). 6. Click the [OK] button. If you selected to export to a file the system will display

the Exported file name dialog box. Specify a name for the file and click the [Save] button. 7. The system exports the map. T O E XPORT

TO

GIS, S PREADSHEET

AND

D ATABASE A PPLICATIONS :

1. On the Data menu, click Export and then click the Geosoft XYZ. The system

displays the Export XYZ data dialog box.

2. Specify the XYZ data file to export as Geoexport and click the [Template]

button. The Export XYZ Template dialog box is displayed.


3. All of the channels automatically included to be exported. If you wish to remove

certain channels from the export process highlight the channels in the Channel box and click the [Remove] button. Click the [OK] button to once you have selected the data you wish to export. The system will return you to the Export XYZ data dialog box. Click the [OK] button again and the system exports the data. Note: The Include Comment Header option is not default, but may contain important information that pertains to the database you are exporting. The Include Dummies option allows you to omit dummy values when exporting.

Printing Maps By default, the system is set up to use your current Windows driver. When you start printing maps for the first time, you will most likely accept the defaults. Depending on your driver’s performance however, you may want to add a new configuration that uses a more advanced printing option, such as Geosoft bands, Geosoft bands and dither, or HP-RTL. Refer to the on-line help system for a complete discussion on the pros and cons of the different printing modes. Printer and Page Setup For optimal printing, you may have to experiment with printer settings and properties. Different drivers allow different selections (paper size, orientation, dithering patterns and colour controls). However, they can be very slow especially for large plots.

240 Tutorial 13: Exporting and Printing Maps T O C ONFIGURE

YOUR

P RINTER

AND

P AGE ::

1. Make sure your GeoDemo.gpf project is open. 2. On the File menu, click Printer and Page Setup. The Page Setup dialog is

displayed.

3. Use this dialog to specify your page setup, i.e. Paper Size, Paper Source,

Orientation (Portrait or Landscape), and Margins. 4. Click the [Printer] button to configure your printer settings.

Tutorial 13: Exporting and Printing Maps 241 5. Use this dialog to select your printer and to modify your printer properties. Click

the [OK] button twice to exit these dialogs. Change or Add New Printer Configuration Use the Change Printer Configuration/Add Printer Configuration dialog(s) to change the configuration of your printing mode, colour scaling and other print options. T O A DD

A

N EW P RINTER C ONFIGURATION :

1. On the Print dialog, click the [Add Config] button. The Add Printer

Configuration dialog is displayed.

2. If you want to use Windows drivers for printing make sure Windows is selected

for the Print Mode. 3. If you are having problems with your Windows drivers and want to optimize your

printing speed, select the Geosoft bands or Geosoft bands and dither Print Mode. 4. Select the Geosoft HP-RTL device if you have this type of printing device. 5. If you want to adjust the Colour Scaling, change the CYMK colour values. 6. If you want to adjust the Image print resolution change the default dpi value. 7. Click the [OK] button and the system will save your new configurations and

initializes it for use. Note: To change your printer configurations click the [Change Config] button from the Printer Setup dialog box.

242 Tutorial 13: Exporting and Printing Maps

Print Preview Use the Print Preview dialog to display the active map, as it would appear when printed. T O P REVIEW

A

M AP B EFORE P RINTING :

1. On the File menu, click Print preview. The Print preview dialog is displayed.

2. From this dialog you can specify the Region to Plot, the Plot Scale, Overlap and

Layout of the file you wish to print. Click the [Preview] button. The system displays a preview of how your map will look when printed on paper. 3. Click the [Print] button if the map is ready for printing or click the [Close] button

to return to the Print Preview dialog box. Print a Map Use the Print dialog to specify how you want your print job to appear and to send a job to the printer. T O P RINT

A

M AP :

1. Select (highlight) the map that you would like to print. 2. On the File menu, click Print. The Print dialog is displayed.


3. Specify the Region you want to print (current Viewed Area or the Entire Map). 4. Specify the Plot Scale. To maintain the map scale, select the Use Scale Factor

option and specify a value, (1 = 100 per cent). If you use this option, the map may require more than one page depending on the media to which you are printing or plotting. 5. If the plot is being led, specify either the All s option or the Range of

s option to print. If you are printing multiple s, you can specify an overlap in mm. This helps you to match s later. 6. Specify the number of Copies to be printed. 7. If required, select the Print to File option box and specify a filename. 8. Select the Centre on Page option box to centre the plot on the page. To centre the

plot on a paper roll select the Fit On Roll option box. 9. To move the map from its origin (lower left corner of page or plot), specify an

offset distance in mm. 10. Click the [Print] button to send the map or plot to the currently configured printer

or plotter. Printing in Batch For high efficiency automated printing and plotting, Geosoft provides a batch printing capability. This capability allows a number of plots to be printed sequentially without any hands-on intervention.

244 Tutorial 13: Exporting and Printing Maps T O P RINT

IN

B ATCH :

1. On the File menu, click the Batch printing. The Print Multiple Maps dialog is

displayed.

2. In the Maps to Print box, specify the maps you want to print. To specify more

than one map, map names should be separated by a ‘|’ (vertical bar) character. You can also select multiple files by clicking the [Browse] button. In the Maps to Print dialog box press and hold the [Ctrl] key and while clicking the left mouse button to select the maps you wish to print. 3. Specify the other parameters as required. For more information about Batch printing options click the Help (

) button.

4. Click the [OK] button. The system sends the maps to the installed printer or

plotter.

Tutorial 14: 3D Viewer 245

Tutorial 14: 3D Viewer The 3D Viewer has been redesigned to streamline your workflow and enhanced usability. The 3D Viewer provides all of your 3D-mapping tools, functions and settings in one integrated 3D environment. When you display a 3D view, either by using the 3D/Open 3D Viewer menu option, or by selecting (doubling-clicking) a 3D view in the View/Group Manager Tool, or by simply double-clicking a 3D view in an open map file, the 3D view will be displayed in the 3D Viewer. The 3D Viewer consists of an interactive dialog, with five main Menus (Add to 3D, Utilities, Settings, Export and Help), a 3D Viewing window, a 3D Tools window and the bottom Status Bar.

3D Views in Oasis montaj Oasis montaj 3D views are a representation of a 3D drawing space on a standard Geosoft map. The 3D capabilities enable you to display multiple surfaces, each with its own relief and contents, and each with its own orientation in 3D space. To create 3D views requires the licensed processing engine, but 3D views on an existing map can be viewed and manipulated in the Oasis montaj free Viewer. Geosoft Maps use Views to organize and display information. Most Geosoft maps contain both a Base view and a Data view, but some maps may have more views for different purposes. Views contain Groups, and these groups in turn contain drawing

246 Tutorial 14: 3D Viewer

elements. All Groups within a 2D View are drawn in the coordinate system of that View. The Base view uses coordinates in millimetres relative to the final printed paper, and the Data view uses a coordinate system that can represent a projected or geographic coordinate system on the earth, or simply an arbitrary X, Y Cartesian coordinate system. 2D Views contain one flat drawing surface, which is defined by the View’s coordinate system. Like 2D Views, a 3D view also represents coordinates, but in this case in X, Y AND Z. 3D Views may contain Voxel (3D Grids) and any number of drawing planes. Any Group or drawing object that can be drawn on a 2D View can be drawn on a Plane in a 3D View. Each plane in a 3D view can be oriented independently in the 3D coordinate system. A Plane in a 3D view can be flat or it can have a surface relief defined by a grid file. Planes will normally share the X, Y coordinates of the 3D view, and flat planes will have a constant Z value representing the vertical location of the plane. However, a plane coordinate system may be oriented in any direction in the 3D space for special applications. If a plane does have a relief View, the axis of the relief is always in the Z direction of the plane. 3D views appear on a 2D map as a standard view, except that what you see is the 3D representation of the view from a fixed viewing location. You can manipulate a 3D view using the 3D Viewer. To do this, select the 3D view (note that you must be in Map View Mode to select a view), right click and select 3D Viewer from the popup menu, or simply click the Open 3D Viewer icon ( ), and the 3D view will be displayed in the 3D Viewer. When viewing the 3D view in the 3D Viewer, you can change the orientation of the View relative to your point of view by rotating the coordinate system horizontally and vertically, and you can zoom and pan into the view, and you can modify certain display parameters such as delete planes, and adjust plane transparency using the 3D Tools. The 3D Tools enable you to modify the 3D parameters, display characteristics and the appearance of your 3D view in the 3D Viewer. The 3D Tools are available in the window on the left side of the 3D Viewer. Additional options are available using the 3D Viewer menus, Add to 3D, Utilities, Settings, Export and Help. When you close the 3D Viewer window, the 3D View will be drawn on the 2D Map as it last appeared in the 3D Viewer. Display a New 3D View in 3D Viewer Using the 3D|Create a New 3D View menu option you can add a new 3D view to a new 3D map or a current map. The 3D Viewer provides an integrated 3D enviroment that includes all of the tools, functions and settings to create a 3D map. Using the 3D Viewer you can add any number of 3D and 2D views and groups to your map, including; planes, relief surfaces, grids, voxels, isosurfaces, drillholes, 3D symbols, a variety of 2D map tools, and 3D import file formats.

Tutorial 14: 3D Viewer 247 TO

OPEN A NEW

3D

VIEW IN THE

3D V IEWER :

1. On the 3D menu, select Create a New 3D View (

). The Create a 3D View

dialog will be displayed.

2. In the View name text box, specity a name for your new 3D view (default is 3D). 3. Then, using the radio buttons (

) in the Display In section, select to display the new 3D view in a New map or the Current map (map_name.map). Note that, the map name that the 3D view is to be added to is displayed to the right of the Current map radio button.

4. When you select New map, the Map name and Map template parameters will

become enabled. Specify the parameters as Map name (3D map.map) and Map template (landscape letter), and click the [OK] button. A new empty 3D view will be created and displayed in the 3D Viewer.

248 Tutorial 14: 3D Viewer Note:

Note:

An empty 3D view will display the following message in the 3D view area, "This 3d View contains No Surfaces or 3D Groups." You can use the Add to 3D menu options to add items to your 3D view.

It is extremely important that when you create a new 3D view that you create a new name for the view rather than selecting a name from the dropdown list. The dropdown list is presented to enable you to see what view names you may already have. Do not overwrite one of the existing 2D views, unless you want to replace it.


To add a Plane to an Existing 3D View A 3D View may contain any number of planes and new planes can be added to any 3D View. TO

ADD A

P LANE

TO AN

E XISTING 3D V IEW :

1. With the 3D Viewer open, select the Add to 3D|Plane menu option (or click the

Add Plane ( ) button) and the Add a new drawing plane to a 3D view dialog dialog will be displayed.

2. Enter the Name of new plane in 3D view or for our purposes you can use the

default name (Plane1) (Note: if you enter the name of an existing plane, that plane will be replaced) and specify the Plane elevation as (10). You can also select a Surface Relief grid (optional) if you would like the plane to have relief. For more information, click the Help (

) button.

250 Tutorial 14: 3D Viewer 3. Click the [OK] button. The new plane is added to the current 3D view in the 3D

Viewer.

4. Using the Navigation tools and the 3D Tools in the 3D Viewer window you can

orientate the view to the desired perspective and when you are satisfied with the orientation close the 3D Viewer. 5. The 3D view is placed in the center of the current map. Using the standard 2D

map tools, you can move and size the 3D view into the desirable position on the map. Draw a group directly onto a plane in an existing 3D View You can draw groups including grids, images, contours, and symbols to a plane in a 3D view just like drawing to a 2D view. After creating a 3D view, it becomes your Default Drawing View so that the next group you plot will be drawn on the Default Drawing Plane which is the most recent plane in the view unless you have set it otherwise. You can also use the clipboard to cut/copy groups from other maps to the default drawing plane of a 3D view.

Tutorial 14: 3D Viewer 251 TO

MAKE A PLANE THE DEFAULT DRAWING PLANE :

1. Select the emplty 3D View in your open map (3D map.map), making sure you

are in View mode by selecting the Map View Mode (

) button.

2. Right click and from the popup menu select 3D Viewer. The emplty 3D view

created in the previous procedure will be opened and displayed in the 3D Viewer. 3. With the Planes & Surfaces item (Plane1) selected (

) and highlighted in the 3D Viewer, on the Add to 3D menu, select 2D Map Tools|Grid and Image Display|Colour-Shaded Grid. The Colour-shaded grid image dialog will be displayed.

4. Using the Browse button you can select the Grid name, (tfmag.grd) from your

working directory. Note that, there is a large variety of grid and image formats available for import. 5. You can leave the remaining parameters to the intelligent defaults and click the

[Current Map] button.

252 Tutorial 14: 3D Viewer 6. The colour-shaded grid will be displayed on the current drawing plane (Plane1)

in the 3D Viewer. Note that, when you close the 3D Viewer your 3D view will be displayed in the centre of the map file.

To Plot 3D Colour Range Symbols Oasis montaj provides a range of options for visualizing your data in three dimensions including; displaying multiple surfaces, each with own relief and contents, and each with its own orientation in 3D space. The 3D colour range symbol plotting option enables you to plot 3D symbols with fixed or variable colours to a 3D map. The colours can be varied based on the values from another data channel. This example uses the sample data (geochem.gdb) found in the \Geosoft\Oasis montaj\data\various directory. T O P LOT 3D C OLOUR R ANGE S YMBOLS : 7. Open the database (geochem.gdb). Then, on the 3D menu, select Create a New

3D View (

). The Create a 3D View dialog will be displayed.

8. In the View name text box, specity a name for your new 3D view (default is 3D)

and then using the Display In radio buttons (

), select New map.

Tutorial 14: 3D Viewer 253 9. Specify the Map name as (3D geochem.map) and the Map template as

(landscape letter) and click the [OK] button. A new empty 3D view will be created and displayed in the 3D Viewer. 10. On the Add to 3D menu, select 3D Symbols. The 3D Coloured symbols plot dialog

is displayed.

11. Using the dropdown lists, select the Z channel as (Cu). We can leave the Mask

channel blank and select the Symbol as (sphere) and the Symbol size (mm) as (50). 12. If you would like to colour your data using the values from a secondary channel,

select Colour option as (Variable colour) and select the Variable colour:Colour data channel as (As) (note that, for information on these or any dialog parameters, click the Help (

) button).

254 Tutorial 14: 3D Viewer 13. As this is Geochemistry data, the Colour table zone method can be selected as

(Log-linear). Click the [OK] button to plot the 3D colour range symbols to the 3D Viewer.

14. The 3D Viewer enables you to change the point of view and work with all the

attributes that make up the 3D view by using the controls available with the 3D Tools.

Tutorial 14: 3D Viewer 255 15. When you close the 3D Viewer the view will appear on the associated 2D map

just as it last appeared in the 3D Viewer.

Displaying a Voxel in a 3D View Use the Add to 3D|Voxel menu option to place a Voxel in a 3D View. A "voxel" is just another word for a 3 dimensional grid. You can create a Voxel using the Voxel Gridding option on the 3D menu (see page 122, for more information on creating a Voxel). T O D ISPLAY

A

V OXEL

IN A

3D V IEW :

1. On the 3D menu, select Create a New 3D View (

). The Create a 3D View

dialog will be displayed. 2. In the View name text box, specity a name for your new 3D view (default is 3D)

and then using the Display In radio buttons (

), select New map.

3. Specify the Map name as (Voxel.map) and the Map template as (landscape

letter) and click the [OK] button. A new empty 3D view will be created and displayed in the new map in the background and in the 3D Viewer in the foreground of your project. 4. On the Add to 3D menu, select Voxel. The Place a Voxel in a 3D View dialog is

displayed.

256 Tutorial 14: 3D Viewer

1. Using the Browse (

) button, select the Voxel file, included with the tutorial data files, copied to your project directory as (Tutorial_Assay_As.geosoft_voxel).

2. We can then leave the remaining parameters to the intelligent defaults, click the

[OK] button and the Voxel file is displayed in the 3D Viewer. 3. By selecting (highlighting) the 3D Object (VOX_tutorial_assay_as) the 3D tools

become enabled. Using these controls enables you to change the different attributes that make up the 3D View. For example, slide the Transparency slider to the centre (50%). 4. When you close the 3D Viewer, the Voxel will appear on the 2D map

(Voxel.map) just as it last appeared in the 3D Viewer. Plotting Voxel Isosurface (Contour) Use the Add to 3D|Isosurface menu option to extract an isosurface from a voxel and plot it to a map. T O P LOT V OXEL I SOSURFACE

TO A

3D M AP :

1. Make sure the Voxel map file (Voxel.map) created in the previous step is open.

), double-click the 3D voxel view, or rightThen, while in Map View Mode ( click and select 3D Viewer from the popup menu, to display the 3D Viewer. 2. On the Add to 3D menu, select Isosurface. The Plot Voxel Isosurface dialog is

displayed.


3. Using the Voxel file (

) button, select (Tutorial_Assay_As.geosoft_voxel).

4. Specify the Surface value as (10). The surface value is the 3D “contour” value.

Click in the Colour box to display the Color tool. Select a suitable colour for the Isosurface, such as light yellow (

).

5. Click the [OK] button and the Isosurface will be plotted to your current 3D View. Note:

For a better view of the Isosurface, in the 3D Tools window uncheck the Voxel (Tutorial_Assay_As.geosoft_voxel) or move the Transparency slider for the Voxel to the right until you can see both the Isosurface and the Voxel.

258 Tutorial 14: 3D Viewer 6. Repeat the steps 2 to 5 above, adding Surface values (contour levels) to best

display your data as (10, 20 and 30). 7. The 3D Voxel map shown below has had Isosurfaces plotted at 10, 20 and 30 and

the Voxel has been deselected (unchecked).

Working with the 3D Viewer The 3D Viewer has been redesigned to streamline your workflow and enhanced usability. The 3D Viewer provides all of your 3D-mapping tools, functions and settings in one integrated 3D environment. When you display a 3D view, it will be displayed in the 3D Viewer. The 3D Viewer consists of an interactive dialog, with five main Menus (Add to 3D, Utilities, Settings, Export and Help), a 3D Viewing window, a 3D Tools window and the bottom Status Bar. For more information on each of the menu options, click the ) button on the dialog of interest. Note: For more detailed information on the 3D Viewer select (highlight) the 3D Viewer and press the Help menu, or use the Search tab in the Oasis montaj help system to locate the 3D Viewer help topic(s). Help (

The Geosoft 3D Viewer provides an interactive 3D view of your data and is used along with the 3D Tools and menu items to interactively control the appearance of your 3D view. When you are satisfied with the appearance of your 3D view in the 3D


Viewer, simply close the 3D Viewer window (click the 3D view will be displayed on your current map.

top-right corner) and the

Once a 3D view has been added to a map the 3D view can be modified by opening the 3D view using the Open 3D Viewer ( ) button and the 3D view will be opened for edit. When you are satisfied with your changes, closing the 3D Viewer saves your changes and displays the updated view on the current map. 3D Tools The parameters available in the 3D Tools window are dependent on the type of 3D group currently selected. Each group enables you modify different aspects of the 3D view within the 3D Viewer. For more information on the individual 3D Tools options, see the “What can I do with the 3D Viewer Tools?” section in the About the 3D Viewer Help topic (click the Help menu on the Geosoft 3D Viewer). 3D Viewing Window

The following interactive viewing buttons are provided on the toolbar directly above the 3D Viewing window.

For more information on the individual 3D Viewing options, see the “What can I do in the 3D Viewing Window?” section in the About the 3D Viewer Help topic (click the Help menu on the Geosoft 3D Viewer). Status Bar The Status Bar across the bottom of the 3D Viewer, displays helpful navigation hints, along with the current 3D view's coordinate system, the shadow cursor location, the view's inclination, declination and look-at point (center of rotation). Notes about 3D Views 3D Views are rendered coarsely when interactively changing the orientation or point of view. When you release the mouse in any of these modes, the objects will be refined in a way that is optimum for the given point of view. The time it takes to refine the picture depends on processor speed, your 3D Graphics capabilities, the complexity of the 3D object being drawn (number of planes, number of groups, relief resolution, etc.), and the amount of RAM on your system. If a plane has a relief View, the groups drawn on the plane will only appear where the relief View is defined. Groups drawn on flat planes (those without relief Views) will be drawn to the extents of the group. 3D Views may have clipping areas just like 2D Views. In 3D, the clip area is applied vertically relative to the X, Y coordinate of each plane.

260 Tutorial 15: Seeker

Tutorial 15: Seeker The Geosoft Seeker tool was designed to retrieve spatial data stored on global and corporate spatial servers – Geosoft DAP servers, USGS servers, from the many WMS and ArcIMS Image servers currently available, as well as retrieve data from the Web and locally from your desktop, using Geosoft's Desktop Cataloger. For more information about Desktop Cataloger, visit http://www.geosoft.com/pinfo/free/desktop-cataloger.asp From the Seek Data menu, select Seeker to deploy the new Seeker tool, designed to minimise your spatial data discovery efforts.

3 easy steps: 1 – Search – using easy to advanced search tools, locate the data you are seeking 2 –View Results – view metadata, quick thumbnail views or full preview map 3 – Cart Selections – directly into open map or project

For more information on DAP servers, see the Geosoft DAP section on page 264.

Tutorial 15: Seeker 261

To a Dataset The Seeker tool enables you to find, view and a dataset in 3-easy steps. To begin open a projected map in your Oasis montaj project. The Seeker will search for and display data that is within the open map’s extents. 1. On the Seek Data menu, select Seeker. The Seeker tool will be displayed in the

Search step. If the AOI displayed in the Interactive Map window is not the same as your open map, click the Update Area of Interest from Open Map ( ) button from the Navigational tools bar. To narrow the search to a specific region or data type, you can specify a text string in the text box, such as (Magnetics) and press <Enter>. 2. The Results step is opened, displaying your default DAP server search results.

You can view other data source results by clicking the data source on the Server Manager Menu. The data results are also available in three views (Tree, List and Thumbnail). When viewing the results in tree or list view, if you hover your cursor over the data icons (e.g. , , ) a popup thumbnail image with a View Metadata link will be displayed. To select ( ) a dataset Check the box in front of the file name, click the Preview Map tab, and the selected datasets will be displayed in the preview map window. When you are satisfied with your data selections, click the Cart step. 3. The Cart step enables you to select a dataset for , and to display a

selected dataset in the globe data explorer, Dapple. To specify options, click the Options tab. This tab enables you to specify options for all the datasets and for individual datasets. When you are satisfied with the settings, click [Retrieve] and the selected datasets will be ed directly to you open map. Click the Close

button to close the Seeker tool.

Step 1: Search The Seeker's Step 1: Search step enables you to query your data sources to determine what data is available that matches your area of interest (AOI). Available data sources include, DAP, WMS and ArcIMS image servers, the Web and your Desktop (see Geosoft's Desktop Cataloger online for more information: http://www.geosoft.com/pinfo/free/desktop-cataloger.asp). When you open the Seeker tool the initial Search extents are based on your current open map. If you do not have an open map, the AOI is the whole world. For advanced metadata query, click the Advanced tab located top-right on the Search step. S EARCH T OOLS

The Search Tools include the Set Default Browser Map and Regions menu, Text Search, Area of Interest Search and Advanced Search.


Set Default Browser Map and Regions – use the Set Default Browser Map and Regions

menu to select your default DAP server (data source) from a list of DAP servers, or add a new DAP server to the list. The default DAP server sets the default browser map (area extents) and the sets the parameters for the Regional selection dropdown list. Text Search – specify text strings to filter your Search criteria so that only datasets

that intersect your AOI and/or contain text that matches a text string will be displayed on the View Results step. Use the text box to add new text strings or to modify text already included on the list. You can type in multiple words and use wildcards (*) and logical operators (AND, OR, AND NOT). Area of Interest Search – includes the Regional Selection List, which is provided

through the default DAP Server (see the Set Default Browser Map and Regions option above). This can be a very handy list that can include countries, province/state boundaries, or mapsheet/quadrangle names. The Interactive Map window enables you to view and redefine your AOI. Use the Navigational tools or Geographic (long, lat) search to redefine your AOI interactively while you view the changes in your interactive map. Advanced Search – enables you to select the intersection of the datasets with the AOI,

as Overlapping or Entirely within the area of interest. The Advanced tab also provides Structured Metadata Query tools that enable you to design a structured query, using Boolean operators and predefined dropdown lists made available through the selected data Source. Your structured search criteria can be Saved for future use and then Loaded to reapply the same search criteria at a later time. Note that, DAP v11.2 s structured metadata query. For more information click the Seeker tool.

button on the

Step 2: View Results The Seeker's Step 2: View Results step enables you to view the results of the current search for all your data sources; DAP, WMS and ArcIMS Servers, the Web and your Desktop (see Geosoft's Desktop Cataloger for more information). You can view the search results using easy-to-navigate tabs in Tree view (with folders), List view, and Thumbnail view. Each of the data sources will be presented on the Server Manager menu bar. Select a data source (DAP, Web, Desktop, WMS, or ArcIMS) to view the results, you will also be presented with the statistics for the number of results found per data source. V IEW R ESULTS T OOLS

The View Results Tools include the Server Manager Menus, Viewing Result Tabs, Preview Map Window and a Metadata Window. Server Manager Menus - select the server search results you wish to view (DAP, Web, Desktop, WMS, or ArcIMS). When you select a data source the result statistics, with the number of results found per data source are presented. The statistical results can


be found to the right of the file name in Tree view and below the Server Manager menus in List and Thumbnail views. Note: Depending on the data source some views may not be available. When this occurs, you will be notified with an appropriate message. Viewing Result Tabs – enable you to view your search results in Tree View, List View and Thumbnail View. The available views depend on the data source (DAP, Web, Desktop, WMS, or ArcIMS) you are viewing, not all data sources can be displayed in all data views. Check ( ) a dataset, in any view, will display an image of the dataset in the Preview Map window, display the dataset's metadata in the Metadata window, and add the dataset to the Cart step for . Preview Map Window – displays a preview image of a selected

dataset from the Results step. The Preview Map included Navigation Tools that enable you to zoom in, zoom out and zoom to fullmap and toggle the AOI and Browser Map. Metadata Window - Metadata (data about data) is captured by Oasis montaj from the

first time the data is touched. The metadata information, which is based on ISO 19139 standards, is stored inside the data (if ed) or as a companion XML file. For more information click the

button on the Seeker tool.

Step 3: Cart Selections The Seeker Step 3: Cart Selections step displays all the datasets you currently have selected for . The list can include data from different servers. For additional options, select the Options tab. To a file, select (highlight) the file to and click the [Retrieve] button. To select multiple files for use the <Shift> or keys while selecting files. For additional options, click the Options tab located on the top-right of the Cart step. D OWNLOAD C ART S ELECTION T OOLS

The Cart Selection tools includes a List of Selected Data for , an Options tab, and [Retrieve] and [Dapple] buttons, as detailed below. ed data will be displayed in your current open map, or if you do not have a map currently open, the ed data will be displayed in a new auto-generated map (when applicable). List of Selected Data for – derived from all selected

data from the Results step. Datasets from multiple data sources (DAP, WMS and ArcIMS Servers, the Web and your Desktop) may be displayed in the list of selected data. Options - enables you to specify options for “all” or “individual datasets”.

Select (highlight) a dataset in the Cart list to enable the Individual Datasets options. [Retrieve] - click to (or open, if the data source is the Desktop) the selected

datasets to a new or current map, if applicable.


[Dapple] - click to launch Dapple, Geosoft’s globe data explorer. Selected datasets

should automatically appear on the 3D globe. For more information click the button on the Seeker tool.

Dapple Geosoft’s globe data explorer Dapple, is a free utility that enables you to browse, discover and display graphically rich data from global and corporate spatial servers – Geosoft DAP servers, ArcIMS image servers and the many WMS servers currently available. The Dapple project is an open-source activity sponsored by Geosoft and derived from the NASA World Wind (http://worldwind.arc.nasa.gov/) open source project. Dapple represents our effort to make this powerful technology accessible and useful to professional earth scientists. For more detailed information about Dapple, visit http://dapple.geosoft.com/default.asp Dapple includes a set of menus (Tools, Servers, View, Settings, and Help), an interactive Globe Explorer window that displays the selected data layers, a Search window that enables you to define your ‘Area of Interest’ via Servers or the Web based on spatial extents and keywords, a Data Layers window that displays the selected data, an Overview Map window that displays your current spatial extents, and a Metadata window that displays the metadata for the currently selected Data Layer. For more information or to Dapple, visit; http://dapple.geosoft.com/

Geosoft DAP Geosoft DAP fits into a service-oriented architecture (SOA) and provides the technology for catag, managing, delivering and visualizing large, spatial earth science data. With Geosoft DAP your data is instantly accessible and easily shared among all the people and teams that need exploration data to make decisions within your organization. How it Works Geosoft DAP is a publishing service that makes spatial data placed on a file system available to a networked environment, and accessible via a web browser or web client application, such as ESRI’s ArcIMS. Once published to a DAP Server, data can also be accessed from a variety of desktop (‘thick’ client) applications including Geosoft’s Oasis montaj, Target and Geosoft Extensions for ArcGIS. You now have two options for accessing data. You can use the new Seeker option, Geosoft's next generation in spatial data retrieval, which enables you to Search for


data stored on global or corporate servers, web servers, and locally from your desktop, or you can use Dapple Geosoft's globe data explorer. Geosoft has also developed plug-ins to DAP-enable ArcGIS and MapInfo. s benefit from easy and transparent access to all available data from their desktop. Thin clients, like Geosoft’s DAP Data Explorer use a web browser to browse, view and extract data from a DAP server. Visit http://www.geosoft.com/pinfo/dap/trydap.asp and see how it works! DAP’s main features include: •

Broadest connectivity to mineral exploration data and information sources including ESRI and AcQuire Technology Solutions.

•

Scales to enterprise requirements for cataloguing, managing and accessing 100's of thousands of spatial and subsurface datasets.

•

Simplifies how you find, use and manage your exploration data.

•

Connects all data stores to industry leading exploration applications including Geosoft Oasis montaj, Target, ESRI ArcMap, MapInfo, and Dapple.

Use the Seek Data option to launch Seeker, Geosoft’s DAP data retrieval tool.

Desktop Cataloger The Geosoft Desktop Cataloger is a free utility that helps you build a catalog of your spatial files from your local drives, and lets you easily find that data when using the Geosoft Seeker tool, or Dapple, Geosoft’s globe data explorer. With Desktop Cataloger, you build a My Data catalog of spatial files by selecting folders on your computer or external drives (can not catalog network drives). You can also specify data types to be cataloged from a preset list of spatial data set file types. The list of ed data types includes ECW, ERS, GDB, Geosoft VOXEL, Geosoft GRD, ArcGIS LYR, ArcGIS SHP, MapInfo TAB and GeoTIF Images. For more information or to Desktop Cataloger, visit http://www.geosoft.com/pinfo/free/desktop-cataloger.asp

Authorizing Your Internet Communication Settings The Authorize Internet Communication dialog box enables you to authorize what communication takes place between your Oasis montaj system and the Geosoft Internet Server. The Internet Trust Relationship dialog box enables you to select the default setting for authorizing all future communication with the server. All communication with the Geosoft Server is encrypted for your privacy and security.


Authorize Internet Communication Dialog This dialog box is displayed when Oasis montaj tries to communicate with an internet server. For example, when you try to locate data on the DAP server. • Click the [Authorize] button to authorize the communication and the data. • Click [Deny] to cancel the communication. The data will not be ed. • Click [Security] to view the Internet Trust Relationship dialog box and change your default authorization setting (see below). Internet Trust Relationship Dialog This dialog box enables you to set the type of access you want when communicating with an internet or external server to and install software components. You can select from three levels of access that will define how the Geosoft Server will communicate with your computer: Trusted This setting will automatically authorize all communication with the server. This means that you will not be prompted to each time you data from the DAP server. All communication with the server is saved in a log file on your local computer so that you can check to see what information was sent and received.

This setting will ask you to all communication with the server before proceeding with a . This means that whenever you query the DAP server, the server will show you what is being requested and ask you to authorize it. Click the [Accept] button to give permission to connect to the server or click the [Deny] button if you do not want toconnect. All communication with the server is saved in a log file on your local computer so that you can check to see what information was sent and received. This is the default setting.

Restricted This setting will not authorize any communication with the server. This means that you do not want any communication with the server to take place. With this setting, you will not be able to connect to the server.

Tip:

You can modify your Internet Trust Settings at any time by selecting the Internet option from the GX|Global Settings menu.


Metadata Tool The Metadata Tool is used for viewing metadata, including metadata associated with DAP datasets. Metadata is information about data. Metadata can be simple or complex and the descriptive needs of different kinds of data are infinitely diverse. To allow for this and provide flexibility, Geosoft metadata is stored in a hierarchical data structure called a "meta". The Metadata Tool will display the meta structure (also called a "schema") and the metadata information of a specific data source. Each branch of a metadata structure may contain a set of Attributes with associated Values, and other branches. Following is an example of the metadata that Geosoft may store with Oasis montaj grid files:

Data: The Data branch contains all metadata associated with any spatial data type. The information at the "Data" level is common to all types of spatial data. Grid: This example describes a grid of data, hence there is a "Grid" branch, which contains metadata that is specific to grids. Display: Grids may contain display information about the grid data set, which is stored in the "Grid/Display" branch.


Statistics: Grids may contain statistical information about the grid data set, which is stored in the "Grid/Statistics" branch. Location: The information that locates a 2-D grid array within the "Data" coordinate system is stored in the "Grid/Location" branch.

Tutorial 16: Trend Enforcement Gridding Tool 269

Tutorial 16: Trend Enforcement Gridding Tool This tutorial is designed to demonstrate how you can use the Trend Enforcement Gridding Tool to alleviate a traditional problem in gridding geophysical data, i.e. the aliasing problem that occurs due to the presence of more samples “along the lines” than across lines. This problem leads to obvious effects including ellipsoids or ellipsoidal “beads” between lines in gridded data. There are various solutions to these types of effects including filtering and gridding along trend directions. However, these techniques may reduce geologic signal or obscure local trends. In this tutorial, you will first grid a database and examine the resulting grid. You will notice that there are areas of the grid that have “jagged” edges which can be misinterpreted as faults and that may complicate geologic interpretation. These effects occur as an artefact of the gridding process and are independent of the method (i.e. line-based gridding or random gridding). In the case of random gridding (i.e. using RANGRID), the result would be a “bull’s eyes” effect rather than jagged edges (i.e. from BIGRID). A traditional solution is to add a trend line. This method works as long as you match high values and low values. The Trend Enforcement algorithm is designed to perform this process automatically – smoothly ing highs to highs, and lows to lows. The algorithm also makes sure that the highs and lows do not cross (i.e. backtrack).

Before trend enforcement

After trend enforcement

The Trend Enforcement Gridding Tool algorithm is designed to provide a solution that preserves the character of local trends while eliminating aliasing effects. This tutorial will show you how to: • Create a project (page 270)

270 Tutorial 16: Trend Enforcement Gridding Tool

• • • • • • • • • •

Access the Trend enforcement menus (page 271) Open a database for manipulation (page 271) Grid your data using Bigrid (page 272) Display colour-shaded grid (page 274) Find trends with the Trend Enforcement Tool (page 275) Access trend line channels in the database (page 276) Plot trends (page 277) Add your own trends (page 278) Grid trend enforced data (page 279) Deselect/Select trend lines (page 281)

Before you begin This section describes how to begin working with the Trend Enforcement system in Oasis montaj. The topics discussed in this chapter include: • Create a project • Access the Trend Enforcement menus This tutorial uses sample data provided on the Oasis montaj CD and installed in your C:\Program Files\Geosoft\Oasis montaj\data\trend directory. Before you begin the tutorial you need to create a working directory to store all your data. To start this tutorial, please create a working directory called D:\Tutorial. A general rule to follow in working with Geosoft applications is to avoid working in the Geosoft directory. In these tutorials, we will follow this rule by keeping all the working data in our working directory D:\Tutorial.

Creating a project To work in Oasis montaj requires an open project. An Oasis montaj "Project" controls your working directory. When you create a project, the system assumes that all your project files are located in the same directory. T O C REATE

A

P ROJECT :

1. Start Oasis montaj. 2. On the File menu, select Project and then click New. The New Project dialog is

displayed.


Oasis montaj assumes that your data is in the directory containing this project (i.e. D:\Tutorial) 3. Specify a name and directory for the project. For example, name the project (Trend) and specify the working directory as D:\Tutorial. Note:

4. Click the [Save] button. The system saves the project and indicates it is open by

adding menus to the menu bar, adding buttons to the Standard Short-cut bar and by displaying the Project Explorer window. These are visual clues indicating that you are ready to start working with the system.

Accessing the Trend Enforcement menus The Trend enforcement menu can be accessed from the Grid and Image menu on the Oasis montaj main menu bar. TO

ACCESS THE

T REND E NFORCEMENT M ENU :

1. On the Grid and Image menu, select Gridding and then select Trend enforcement.

The Trend Enforcement menu will be displayed. (TRENDDB.GX) (TRNDPATH.GX) (TRNDDIGI.GX)

2. These menus items (GXs) will enable you to eliminate aliasing effects while

preserving the character of local trends.

Opening a Database In this exercise, you will be working with the database (trend_mag.gdb), which should be copied into your current working directory D:\Tutorial.

272 Tutorial 16: Trend Enforcement Gridding Tool T O D ISPLAY

A

D ATABASE

1. On the Database menu, select Open database. The Open database dialog is

displayed. 2. Select the (trend_mag.gdb) and click the [Open] button. The database is opened

and displayed in a spreadsheet window.

Gridding your data using Bigrid Gridding refers to the process of interpolating data onto an equally spaced “grid” of values in a specified coordinate system, such as X-Y. The Trend Enforcement Tool enables you to use either the Bigrid (Bi-Directional) gridding method for line-based data, and Rangrid (Minimum curvature) or Kriging (Statistical local estimation) gridding technique for random based data. In this exercise we will use the Bigrid method. T O A PPLY B I -D IRECTIONAL G RIDDING

TO

D ATA:

1. On the Grid and Image menu, select Gridding, then select Bi-Directional Line

Gridding. The Bi-directional gridding of line data dialog is displayed.

2. Using the Channel to grid dropdown list, select Mag. Specify the Output grid as

(trend) and specify the Grid cell size, as (25).

Tutorial 16: Trend Enforcement Gridding Tool 273 Note:

If no cell size is specified, the default is ¼ of the line spacing. For more

information, click the Help ( ) button. 3. To access the Advanced gridding parameters, click the [Advanced>] button. The Advanced Gridding options dialog is displayed.

4. You can leave these parameters to the intelligent default values. For more

information, click the Help (

) button.

5. To return to the Bi-directional gridding of line data dialog click the [

button. Click the [OK] button to grid the data. The grid (trend.gdb) is displayed in a temporary map.


Displaying a Colour Shaded Grid When working with the Trend Enforcement Tool system it is sometimes useful to display the data as a Colour-shaded grid. T O D ISPLAY C OLOUR S HADED G RID : 1. On the Grid and Image menu, select Display grid and then select Colour-shaded

grid. The Colour-shaded grid image dialog is displayed.

Tutorial 16: Trend Enforcement Gridding Tool 275 2. Using the Grid name dropdown list, select (trend.grd). Leave the remaining

parameters to the default values and click the [Current Map] button to display the Colour-shaded grid on the current map (trend.grd).

Colour-shaded grid displaying aliasing effects

Finding Trends A traditional problem in gridding geophysical data is the aliasing problem that occurs due to the presence of more samples “along the lines” than “across lines”. This leads to obvious effects including ellipsoids or ellipsoidal “beads” between lines in gridded data. T O F IND T RENDS : 1. On the Grid and Image menu, select Gridding|Trend Enforcement and then select

Find trends. The Find trend lines in a database dialog is displayed.


2. Using the Data channel for trends dropdown list, select (mag). In the Window for

Max-Min Search box, specify (500) and in the Preferred angle for trends box specify (125). Then, in the Allowable deviation in angle box, specify (30.0) and in the Maximum length for s box, specify (1000). You can leave the remaining parameters to the intelligent default values. For a detailed description of these parameters, click the Help (

) button.

3. When ready to continue, click the [OK] button. The system calculates the Trend

lines and places this information in your database. Note: When using Rangrid as your gridding technique, you must specify a value in the “Re-sampling interval along trends” parameter. If no value is entered, the Trend Enforcement Tool will not calculate the appropriate trend lines. For more information on Finding Trends click the Help (

) button.

Accessing Trend Lines in Database You may want to review your trend lines before you plot them on a map or regrid your data using the trend enforced data. T O A CCESS T REND L INES

IN

D ATABASE :

1. To access the trend lines select your database (trend_mag.gdb). 2. Click on the Line Header Cell (upper left cell). Click the right mouse button.

From the popup menu select List. Another popup menu will appear containing a list of the lines in the database. Scroll down the list and select R0:0 (the minima trend lines). The system displays the minima trend lines (start and end points) in the database.

Tutorial 16: Trend Enforcement Gridding Tool 277 Note:

When you click on a data value (X, Y or Z) in the database, you will notice that the linked map cursor moves to the selected location of the trend line on the map.

Linked data point

Plotting Trend Lines The Trend Enforcement Tool displays the trend lines in the original database. Two new lines will be added, R0:0 (Minima trend) and R1:0 (Maxima trend). T O P LOT T REND L INES : 1. On the Grid and Image menu, select Gridding|Trend Enforcement and then select

Plot trends. The Trend Line path plot dialog is displayed.

2. Using the Colour for minimum trends (R0, R2, etc) and the Colour for maximum

trends (R1, R3, etc), select (red) and (blue) and for Line thickness specify (0.15). (These colours are the opposite of the gridding convention so that these show up clearly on the map.) 3. Click the [OK] button. The No defined map scale dialog is displayed.


4. Note that, this dialog is displayed whenever drawing to a map for which a map

scale has not been defined. This situation most commonly occurs when a map has been opened just to display a grid image (as applies here). A map scale is required to determine appropriate scaling for drawing text, patterned lines, and other map graphic details. 5. Click the [OK] button to accept the default parameters, for more information

click the Help (

) button.

6. The trend lines are plotted on the current map (trend.map).

Trend lines, Maximum values (blue), Minimum values (red).

Adding Your Own Trend Lines The Trend Enforcement Tool may not find all of the trend lines in your database. You can interactively digitize a trend line from a grid and add it to the end of a line in the current database. You also have the ability to resample the trend line to a specified sample interval (necessary when using the random gridding techniques). T O A DD Y OUR O WN T REND

LINES :

1. On the Grid and Image menu, select Gridding|Trend Enforcement and then select

Add trend line. The Add new digitized trend line dialog is displayed.


2. Using the [Browse] button, locate the Grid to digitize as (trend2_s.grd) and from

the Output channel dropdown list, select (mag). In the Re-sample interval box specify (25). (It is recommended that the trend line be re-sampled at the same cell size as the grid.) 3. Click the [OK] button to continue. The Digitize to database dialog box is

displayed.

7. Click the [OK] button to begin digitizing. 8. Draw a Trend Line by selecting points (either minimum or maximum point

values) on the displayed grid. When you are finished each line, click the rightmouse button and select Done. 9. The digitized trend line data values, which have been interpolated to the specified

re-sample interval, will be added to trend line “R2” in the database. Additional trend lines added to the database will be added to the end of trend line “R2” separated by a dummy value ( * ).

Gridding Trend Enforced Data You can now re-grid your data, using the same parameters as the trend.grd. T O A PPLY B I -D IRECTIONAL G RIDDING

TO

T REND E NFORCED D ATA:

1. On the Grid and Image menu, select Gridding, then select Bi-Directional line

gridding. The Bi-directional gridding of line data dialog is displayed.


2. We will be using the same parameters as the original grid (trend.grd) except we

will change the name of the Output grid file to (Trend_2.grd). 3. Click the [OK] button to grid the data and display the grid in a temporary map.

Comparing the two grids We can display the two grids side by side to see the difference the trend enforced gridding has on the data (note that, the grid (trend_2.grd) should be displayed as a colour shaded grid to properly compare the two grids).


The original grid trend.grd (left) the Trended grid trend_2.grd (right). Note: The actual data values and locations are exactly the same in both grids. The Trend Enforcement Tool forces the gridding process to honour the trended data. Trend lines must be selected to be included in gridding. You can deselect the trend line(s) for other processes with the database.

Deselecting/Selecting Trend Lines You may want to deselect/select your trend lines for other processing applications. T O D ESELECT /S ELECT T REND L INES

IN A

D ATABASE :

To access the trend lines select your database (trend_mag.gdb). 1. Click on the Line Header Cell (upper left cell). 2. Click the right mouse button and from the popup menu, select Selections and then

select Selection Tool.


3. The Line Selection Tool dialog box is displayed.

4. Scroll down the list and highlight R0:0 then click the [Deselect highlight] button.

The check mark beside the line is removed. 5. Repeat the previous step for R1:0 and R2:0. Click the [OK] button to continue. 6. To select lines repeat above procedure clicking the [Select highlight] button and

a check mark will be placed beside the line.

Appendix 1: Understanding Spheroids and Datums 283

Appendix 1: Understanding Spheroids and Datums Spheroids A spheroid is an oblate ellipsoid of revolution (basically an ellipsoid) that is used to model the surface of the earth for making maps. A spheroid is defined by an earth radius, which is the major axis of the ellipsoid, and the flattening (f), which can also be expressed as the eccentricity (e) or ellipticity (l).

l = 1/f e = sqrt((2/l) - 1/(l*l)) e = sqrt(2f - f*f ) In the past, as cartographers created maps of different parts of the earth, spheroids were chosen to best approximate the shape of the earth in the region of the map. This led to a number of different spheroids or ellipsoids (such as Clarke 1866, Hayford 1910, etc.) that are in common use for different parts of the world. In some cases, maps of a particular region of the earth have been created with different spheroids and it is necessary to convert coordinates from one spheroid to another. This only works if both spheroids share the same earth centre, which they normally will for older maps. This is because map survey work has normally used gravity as the reference for the earth centre, and maps of the same area will clearly have used the same gravity field. Datums The problem with using spheroids alone to define an earth model becomes apparent when working with satellite locations from GPS receivers. GPS systems commonly base locations on a spheroid known as World Geodetic System 1984 (WGS 1984), which naturally places the centre of the earth at the true centre of gravity. Unfortunately, this differs from the earth centre that has been used for most local maps of the world because these maps use an assumed earth centre based on the local gravity field, which is perpendicular to the geoid at that location. To for this we need a datum. A datum includes a spheroid and an earth centre offset from WGS 1984. Some datums may also include a rotation of the minor axis of the spheroid relative to WGS 1984. Datums for various countries and regions of the world have been compiled and defined in the MAPPROJ.DTM file. W HAT

DOES THIS MEAN ?

What this means is that longitude/latitude in one datum is not necessarily the same as in another datum (there may be an offset and rotation). Before the earth centre was introduced, all we needed was a spheroid (ie. Hayford 1910). This worked fine for projections within the same country or region of the earth because the earth centre was the same. Note that Hayford 1910 is not a datum, it is a spheroid. If the spheroid

284 Appendix 1: Understanding Spheroids and Datums

alone is specified, an earth offset (X,Y,Z) of (0,0,0) with no rotation (see MAPPROJ.DTM) is required. Working with spheroids and datums A common mistake that is made when using coordinate systems in Oasis montaj is to mix coordinate systems based on a spheroid with coordinate systems that use a datum. For example, you may be in South America and you have data that is defined as using the Hayford 1910 spheroid, and you wish to convert this to a local map datum, say the Brazil Corrego Alegre datum, which is based on the International 1924 spheroid with an earth centre offset of (206,-172,6). In this case, your input projection datum should be HAYF1910 (Hayford 1910), and your output projection datum should be INT1924 (International 1924), NOT 55INT924 (Brazil Corrego Allegre). This is because you only know the spheroid of the input, not the full datum, so you must only use the spheroid of the output system and assume that both coordinates use the same earth centre, which is usually the case. The only exception is when dealing with GPS locations based on WGS 1984 as the input coordinate. Here, you in fact do know the full datum of the input because all WGS 1984 has a (0,0,0) offset. In this case, specify the input projection as WGS1984 and the output projection as 55INT924.

Understanding local datums Local datum transforms are used to convert coordinates between different map datums. For example, a local datum transform is required to convert longitude, latitude coordinates on the WGS 84 datum to longitude, latitude coordinates on the NAD27 (North American Datum 1927). The difference in location that arises between map datums can be up to several hundred metres. The key to understanding local datum transforms is an understanding of the geoid and its relationship to a Datum. A geoid is the actual shape of the earth at mean sea level, which is everywhere normal due to the earth’s gravitational force. Because of local and regional variations in the earth’s gravity field, the geoid is not a perfect mathematical form, but rather it has local variations. These variations are illustrated in the following diagram (from Verhoogan, John, Francis J. Turner, Lionel E. Weiss, Clyde Wahrhaftig, William S. Fyfe (1970), The Earth, Holt, Rinehart and Winston, Inc., New York.):

topographic surface geoid ellipsoid


To make maps, an ellipsoid is used to approximate the geoid for a specific region of the world. An ellipsoid is an ellipse rotated about its shorter axis (also called an oblate spheroid), which is what the geoid would be if the mass of the earth were uniformly distributed. A datum is the earth model that is used to map a specific region of the world. A datum includes an ellipsoid (described by the major axis and flattening), the prime meridian (location of 0 longitude, normally Greenwich England), and a tie point, which is the location on the earth at which the ellipsoid and the geoid are the same for the region that the Datum is used. The ellipsoid and tie point have been chosen so that the differences between the surface of the ellipsoid and the geoid are minimised. Most common mapping operations within the same datum are only concerned with the ellipsoid, which is why an ellipsoid name is often used interchangeably with a datum name. With the advent of satellites and later the Global Positioning System, it became necessary to define datums tied to the gravitational centre of the earth (as opposed to being tied to a location on the earth’s surface). Such datums are called geocentric, and the most common example is WGS 84. Most of the difference between an earth surface ties datum and a geocentric datum can be described by a shift in the location of the centre of the ellipsoid (the assumed earth centre). However, there can also be a small rotation difference caused by differences in the direction of North, and a scale factor caused by differences between the elevation of the tie point and mean sea level. In addition, local perturbations of the geoid that result from local gravity variations within a Datum will produce additional “residual” differences. To convert between datums requires knowledge about all aspects of both datums (the ellipsoids, prime meridians and the local perturbations of the Geoid). There are a number of methods used to transform coordinates between datums (see http://www.petroconsultants.com/products/geodetic2.html), although in practice, the following two methods ed in Oasis montaj are the most commonly used: Method 1 The most familiar method is to perform an earth centre shift, rotation and scale, commonly referred to as the Bursa Wolf 7-parameter transform (parameters are X,Y,Z offsets, X,Y,Z rotations and a scale factor). The Molodenski transform is a simplification that deals with three parameters only (X,Y,Z offsets). These transforms are only close approximations to the true perturbations, and datums that cover a large region often require a number of different "local" definitions (for example, NAD27 has at least 6 different transforms to WGS 84). The Bursa Wolf transform is ed in Oasis montaj. Parameters of the transform are listed in the file “datumtrf.csv” for different local datums, and the file “ldatum.csv” contains a reference list based on the common area of use for each datum transform.


Method 2 Some national mapping agencies have carefully measured accurate “residual” differences across a Datum. This is done by measuring the differences between local map coordinates and WGS 84 at numerous locations. Such differences are described by “correction "grids”, which contain longitude, latitude and elevation shifts as a function of location. Examples are NADCON in the US and NTv2 in Canada, both of which are ed in Oasis montaj (NTv2 in Oasis Montaj is a 20 minute approximation of the full NTv2 transform). Note that NADCON and NTv2 are not accurately defined for offshore areas and should not be used for offshore mapping purposes. In Oasis montaj, the residual grids are stored as compressed look-up tables in files with extension “.ll2” in the Oasis montaj/etc directory. The name of the table is found in the square brackets that are part of the local datum transform name. For example, the lookup tables used for local datum transform “*NAD27 NTv2 (20 min) [NTv2]” are found in the file “NTv2.ll2”. Note that Bursa Wolf transforms are very much faster than NADCON or NTv2, and will normally be accurate to the sub-metre level for local regions. In future, as more correction grid models are defined, they will be added to the model list.

Choosing a local datum transform A local datum transform is used to convert coordinates between different datums. The most common example of this is the conversion of GPS locations on the WGS-84 datum to a local map datum. The list below shows the options for the Choose local datum transform dialog box. Datum

The currently selected datum name is displayed for your information. You must go back to the previous dialog to change the datum.

Local datum transform

Select a local datum transform name from the list. Normally, the list will only include known local datum(s) for the Datum specified. If there are no local datum for the datum specified, all datums will be available in the list and the default transform will be “ ”. If you do not know the local datum transform to use, or if you will always be working the same datum, you will want to select the option in this box. When this option is applied, no local transform is used.

[List All]

If the specified datum has a set of known local datum transforms, these will appear in the list by default. However, if you have chosen the wrong datum, and you know the local datum transform, you may choose to list all known local datum transforms.


Local datum CSV files Local datum transforms are listed in the files “ldatum.csv”, which is the list used by this dialog. The local datum EPSG/POSC 1 name is referenced in the “Datum_trf” column of this file, and the “datumtrf.csv” file contains the actual local datum transform parameters. If you add your own custom local datum, it must be added to both files. Each local datum transform has an associated Datum (such as NAD27). If you choose a local datum transform that is for a datum different from the one selected previously, the datum will be changed. This is allowed, but under normal circumstances it means that there is probably something wrong about the coordinate system you are using. Changing the datum should therefore only be done with caution and an understanding of datum issues. Adding your own local datum transform You cannot add lookup-based local datum transforms. You can add your own 7parameter local datum transforms to the datum tables. For example, perhaps we want to define a special version of the “Luzon 1911” datum that we have used which is part of the Philippines. T O A DD

A

L OCAL D ATUM T RANSFORM :

1. To add this datum, you need to modify two CSV files in the Geosoft directory

using the following information: EPSG datum name

The name of the datum on which the local transform is based. This should be an accepted EPSG name, one of the datum names listed in the table “datum.csv”. In this case, the datum is “Luzon 1911”.

Transform name

Choose a name that describes the datum. Since your name is not an EPSG name, you must start the name with a “*” character. For example, “*Luzon special”.

Area of use

Describe the area of use so that the transform can be chosen based on the area. For example, “[Luzon 1911] Philippines -special”. By convention, we include the datum name in square brackets at the beginning of each area of use description.

dX,dY,dZ

Translation vector in metres to be added to a geocentric Cartesian coordinate point in the projection to produce WGS 84 geocentric Cartesian coordinates. For example, “130,-77,-50”. Note that the sign convention is important, and Geosoft conforms to EPSG convention as described

1

EPSG (European Petroleum Survey Group) / POSC (Petrotechnical Open Software Corporation).


here. The inverse sign convention is also in common use elsewhere. rX,rY,rZ

Rotations in arc-seconds (degrees/3600) to be added to a geocentric Cartesian coordinate point vector in the projection to produce a WGS 84 geocentric Cartesian coordinate vector. The sign convention is such that a positive rotation about an axis is defined as a clockwise rotation of the position vector when viewed from the positive direction of the axis. A positive rotation about the Z axis (Rz) will result in a larger longitude. Most transforms (all Molodenski based projections) will use “0,0,0”.

Scale

The scale correction to be multiplied by the geocentric Cartesian coordinate in the map projection to obtain the correct scale in WGS 84 coordinates. This scale is expressed in ppm so that the actual scale is (1 + scale/1,000,000). For example, “0.225”.

2. Once you have gathered this information, edit the file “datumtrf.csv” (this can be

edited in Excel or in a text editor). The first line of the file contains the column header that describes each data field as follows: DATUM_TRF,CODE,MAPINFO,AREA_OF_USE,DATUM,TARGET,DX,DY,DZ,RX,RY,RZ,SCALE

For the transform described in the example above, the line would be: “*Luzon special”,,,"[Luzon 1911] Philippines - special","Luzon 1911","WGS 84",-130,-77,50,0,0,0,0.225

The “CODE” and “MAPINFO” columns are used to reference the EPSG code and MapInfo code when exporting data to these systems. In this case, these codes are not known and are left blank. Unknown MapInfo codes can also be set to “0”. The “WGS84” is specified as the “TARGET” since these transform parameters are relative to WGS84 (by far the most commonly used geocentric datum). 3. Now edit the “ldatum.csv” file and add an entry so that the transform will be

visible to the in the projection wizard dialogue screens. This table contains the following columns: AREA_OF_USE,DATUM,DATUM_TRF

The new entry would be: "[Luzon 1911] Philippines – special ","Luzon 1911","“*Luzon special"

The DATUM_TRF in this file must match exactly the DATUM_TRF column in the “datumtrf.csv ” file.


Oasis montaj coordinate system files and reference tables This section is for s who want to develop their own coordinate systems or know the details of the coordinate system methods used in Oasis montaj. The section contains information on the various files used by Oasis montaj for coordinate systems. GI projection files (*.gi) Map views and databases have the coordinate system information imbedded in the file. Oasis montaj stores all the coordinate system information for a particular grid file (.grd) in a GI (.gi) file. For example, the grid file mag.grd, would have an associated projection file named mag.grd.gi. Important!

When copying a grid file to another directory, you must copy any existing (grd.gi) files associated with the data file in order to maintain the coordinate system information for the grid.

Projection table files Oasis montaj uses CSV files as lookup tables for projection information. These reference files are described in the list below: Reference Files

Description

ipj_pcs.csv

List of all known projected coordinate systems, provides the Transform and the Datum lookup names

transform.csv

List of known transforms of the world, and their parameters

datum.csv

List of known datums of the world, provides central meridian and the ellipsoid lookup

ellipsoid.csv

All known ellipsoids of the world and their parameters

datumtrf.csv

All known local datums, provides Datum lookup and the local datum transform parameters

ldatum.csv

A listing of local datums by area of use. This table is only used by the Projection Wizard

All names in the tables are POSC (Petrotechnical Open Software Corporation) compliant, unless they begin with an *. The asterix usually signifies that the projection is a custom projection.


Projection name tables The following tables are used to define a common set of key parameters for projections and units used in GXF. The first column of each table is a key name, which is unique within each table. Key names that are not POSC compliant start with an (asterisk) character. Table 1: Projection transformation methods This table identifies all defined projection transformation methods. The parameters are listed in the order required in the #MAP_PROJECTION data object. This table was compiled using EPSG (as of 2000/12/28)) as data sources. The order of parameters is based on the enumerated parameter order specified in the EPSG table "TRF_METHOD", with unused parameters omitted. Should EPSG add new methods in the future, GXF for those methods implied, and order of required parameters will be as defined by EPSG. EPSG "Transverse Mercator (South Orientated)" is the same as POSC "Transverse Mercator (South Oriented)", which corrects the spelling of "Oriented". P ARAMETER N OTES :

• • • • •

All distance references must be specified in metres. All geographic references (latitudes and longitudes) are specified in degrees. Longitudes in the Western hemisphere are negative. Latitudes in the Southern hemisphere are negative. Longitudes are relative to the prime meridian of the datum Projection method

Required parameters

Geographic

No parameters. This indicates that coordinates are longitudes and latitudes.

Hotine Oblique Mercator

Latitude of projection centre Longitude of projection centre Azimuth of initial line Angle from Rectified to Skew Grid Scale factor on initial line False Easting False Northing


Laborde Oblique Mercator

Latitude of projection centre Longitude of projection centre Azimuth of initial line Scale factor on initial line False Easting False Northing

Lambert Conic Conformal (1SP)

Latitude of natural origin Longitude of natural origin Scale factor at natural origin False Easting False Northing

Lambert Conic Conformal (2SP)

Latitude of first standard parallel Latitude of second standard parallel Latitude of false origin Longitude of false origin Easting at false origin Northing at false origin

Lambert Conformal (2SP Belgium)


Mercator (1SP)


Mercator (2SP)

Latitude of first standard parallel Longitude of natural origin False Easting False Northing


New Zealand Map Grid

Latitude of natural origin Longitude of natural origin False Easting False Northing

Oblique Stereographic


Polar Stereographic


Swiss Oblique Cylindrical

Latitude of projection centre Longitude of projection centre Easting at projection centre Northing at projection centre

Transverse Mercator


Transverse Mercator (South Oriented)


Equidistant Conic



Latitude of false origin

Polyconic

Longitude of false origin Scale factor at natural origin Easting at false origin Northing at false origin

Table 2: Length units The following table is compiled from the UNIT_OF_LENGTH table in the EPSG tables. The unit names are the abbreviations defined in POSC. This table is for convenient reference only, and the EPSG table is considered the primary reference. Unit

Description

Factor to metres

m

metre

1.0

ft

foot

0.3048

ftUS

US survey foot

0.3048006096012

ftMA

modified American foot

0.3048122529845

ftCla

Clarke's foot

0.3047972651151

ftInd

Indian foot (Clarke)

0.3047995102481

ftSe

foot (Sears)

0.3047994715387

lkCla

link (Clarke)

0.201166194976

lkBen

link (Benoit)

0.2011678249438

lkSe

link (Sears)

0.2011676512155

chBen

chain (Benoit)

20.1167824943759

chSe

chain (Sears)

20.1167651215526

ydSe

yard (Sears)

0.914398414616

ydInd

Indian yard

0.9143985539701

fathom

Fathom

1.8288

nautmi

nautical mile

1852.0

mGer

German legal metre

1.0000135965

dega

Degrees (angular)

n/a

294 Appendix 2: Geosoft Line and Pattern Styles

Appendix 2: Geosoft Line and Pattern Styles Geosoft provides a number of Line and Pattern Styles for use in Oasis montaj. The following table displays the “Family” name of each Line and Pattern Style and some examples. The following five pages include all of the available Line and Pattern Styles that are currently available in Oasis montaj and can be printed and used as a reference. L INE S TYLES Family Name

Examples

P ATTERN S TYLES Family Name

Standard

Solid fill

Fancy

Objects

Geology

Hatches

Arrows

Geology

Slashes

Shapes

Example Solid Orange

STANDARD PATTERNS Solid Line

Long Dash

Dotted

Short Dash

Long, Short Dash

Dash Dot

Pattern #7

Pattern #8

Very Short Dash

Pattern #10

Double Line

Bold Dots

Dots - 2 Pattern #148

Pickets Dash Down - 4

FANCY LINES

Equals

Railroad Dash - 4

Railroad Dash -2

Railroad - Dash

Railroad - 4

Railroad - 2

Railroad

Pattern #150

Pattern #149

Pickets Dash Up - 4

Pickets Dash Up - 2

Pickets Dash Up

Pickets Up - 4

Pickets Up - 2

Pickets Up

Pattern #130

Pattern #129

Pattern #128

Bold Dots - 2

Sidewalk #1

Sidewalk #2

Sidewalk #3

Stripe #1

Stripe #2

Stripe #3

Ecks

Ecks - 2

Ecks - 4

Ecks Line

Pattern #11

Pattern #12

Pattern #138

Pattern #139

Ecks Line - 2

Ecks Line - 4

Pattern #13

Pattern #14

Pattern #140

Pickets Down

Ecks Dash Ecks Dash - 2

Pickets Down - 2

Pickets Down - 4

Ecks Dash - 4

Ecks Dotted

Pickets Dash Down

Pickets Dash Down - 2

Ecks Dotted - 2 Dots

SLASHES

Forward Slash

Forward Slash #2

Forward Slash - Line Down

Forward Slash - Line Up

Forward Slash - Line #2 Down

Forward Slash - Line #2 Up

Backward Slash

Backward Slash #2

Backward Slash - Line Down

Backward Slash - Line Up

Backward Slash - Line #2 Down

Backward Slash - Line #2 Up

Hash

Pattern #501

Pattern #502

Pattern #503

Arrow Forward

Arrow Forward - 2

Arrow Forward - 4

Pattern #507

Dashed Arrow Forward

Dashed Arrow Forward - 2

Dashed Arrow Forward - 4

Pattern #511

Pattern #512

Pattern #513

Arrow Backward

Arrow Backward - 2

Arrow Backward - 4

Pattern #517

ARROWS

Dashed Arrow Backward

Dashed Arrow Backward - 2

Dashed Arrow Backward - 4

Arrows Up

Arrows Up - 2

Arrows Down

Arrows Down - 2

Pattern #525

Pattern #526

Pattern #527

Arrows Line Up

Arrows Line Up - 2

Arrows Line Up - 4

Arrows Dash Up

Arrows Dash Up - 2

Arrows Dash Up - 4

Pattern #535

Pattern #536

Pattern #537

Arrows Line Down

Arrows Line Down - 2

Arrows Line Down - 4

Arrows Dash Down

Arrows Dash Down - 2

Arrows Dash Down - 4

SHAPES

Empty Triangles Down - 2

Empty Triangles Down

Filled Circles #2

Filled Star of David

Filled Circles

Empty Circles

Empty Star of David

Filled Star of David - 2

Filled Diamonds

Empty Star of David - 2

Empty Circles #2

Filled Diamonds #2

Empty Diamonds #2

Empty Star

Filled Star - 2

Filled Star

Filled Triangles Up

Empty Star - 2

Empty Diamonds

Filled Triangles Up - 2

Filled Square

Empty Square - 2

Empty Square

Filled Square - 2

Filled Triangles Down

Filled Triangles Down - 2

Empty Triangles Up

Empty Triangles Up - 2

Fault

Shear

Pattern #203

Right Fault Line

Pattern #205

Right Fault Line - 2

Pattern #207

Right Fault Line 4

Pattern #209

Right Fault

Pattern #211

Right Fault 2

Pattern #213

Left Fault Line 2

Pattern #219

Left Fault Line 4

Pattern #221

Left Fault

Pattern #223

Left Fault 2

Pattern #225

Left Fault 4

Clastic Shear

Thrust

Thrust 2

Pattern #230

Thrust Line

Right Fault 4

Pattern #215

Thrust Line 2

Thrust Line 4

Left Fault Line

Pattern #217

Line Thrust

Geosoft GEOLOGY Linestyles - SHEET 1 of 2

Thrust Dash

Line Thrust - 2

Pattern #270

Half Circle Line

Half Circle Line - 2

Half Circle Line - 4

Half Circle Dash

Half Circle Dash - 2

Half Circle Dash - 4

Half Empty Circle - 2

Half Empty Circle Pattern #259

Pattern #280

Empty Half Circle Line - 2

Empty Half Circle Line

Line Thrust Down - 2

Half Circle Down - 2

Half Circle Down

Empty Half Circle Dash - 4

Empty Half Circle Dash - 2

Empty Half Circle Dash

Empty Half Circle Line - 4

Half Circle - 2

Half Circle

Dash Thrust Down - 4

Dash Thrust Down - 2

Dash Thrust Down

Line Thrust Down - 4

Line Thrust Down

Pattern #260

Pattern #258

Dash Thrust - 4

Dash Thrust - 2

Dash Thrust

Line Thrust - 4

Thrust Dash 2

Thrust Dash 4

Thrust Down

Thrust Down - 2

Pattern #240

Thrust Line Down

Thrust Line Down - 2

Thrust Line Down - 4

Thrust Dash Down

Thrust Dash Down - 2

Thrust Dash Down - 4

Pattern #248

Pattern #249

Pattern #250

Pattern #290

Half Circle Down Line

Half Circle Down Line - 2

Half Circle Down Line - 4

Half Circle Down Dash

Half Circle Down Dash - 2

Half Circle Down Dash - 4

Empty Half Circle Down

Empty Half Circle Down - 2

Pattern #300

Empty Half Circle Down Line

Empty Half Circle Down Line - 2

Empty Half Circle Down Line - 4

Empty Half Circle Down Dash

Empty Half Circle Down Dash - 2

Empty Half Circle Down Dash - 4

Geosoft GEOLOGY Linestyles - SHEET 2 of 2

Empty Circle Dash

Empty Circle Dash - 2

Filled Circle

Filled Circle - 2

Dip Dash Down

Dip Dash Down - 2

Dip Dash Down - 4

Anticline - 4

Anticline Dash

Anticline Dash - 2

Pattern #348

Pattern #368

Pattern #328

Pattern #329

Pattern #349

Anticline Dash - 4

Pattern #330

Pattern #369

Dip Line Up - 2

Stitch - 2

Stitch

Dip Line Up

Dip Line Up - 4

Stitch - 4

Filled Circle Dash - 4

Syncline Dash - 4

Syncline Dash - 2

Syncline Dash

Syncline - 4

Syncline - 2

Syncline

Pattern #370

Pattern #350

Filled Circle - 4

Filled Circle Line

Filled Circle Line - 2

Filled Circle Line - 4

Dip Dash Up

Stitch Dash

Filled Circle Dash

Dip Dash Up - 2

Stitch Dash - 2

Filled Circle Dash - 2

Empty Circle

Dip Dash Up - 4

Pattern #338

Anticline - 2

Anticline

Pattern #360

Pattern #359

Pattern #358

Stitch Dash - 4

Empty Circle - 2

Pattern #320

Pattern #339

Dip Line Down - 2

Dip Line Down

Pattern #340

Pattern #321

Empty Circle Line

Empty Circle Line - 2

Empty Circle Line - 4

Dip Line Down - 4

GEOSOFT FILL PATTERNS

Horizontal Lines

HATCH Alluvium

Vertical Lines

Half Diagonal Right

GEOLOGY

Schist

Diagonal Right

Half Diagonal Left

Horizontal Half

Random Conglomerate

Tuff

Diagonal Left

Conglomerate

Clastic 1

Igneous

Siltstone

Cross Hatch

Staggered Lines

Bricks

Diagonal Basket Weave

Basket Weave

Dolomite

Diamond

Diagonal Cross Hatch

Mudstone

Chert

Vertical Half

Clastic 2

Clastic 3

Volcanic 1

Volcanic 2

Volcanic 3

Hexagonal Triangles

OBJECTS Dots

Random Triangles

Plus

Hexagonal Dots

Random Dots

Diagonal Plus

X'es

Dashes

Boxes

Random Plus

Random Circle

Circle

Diagonal Boxes

Random Boxes

Triangles

300 Glossary

Glossary array channels

channels column database datum

desktop

Special channels in columns of the spreadsheet that contain multiple channels of data. Array channels are represented graphically by a curve in the spreadsheet. See also channels, sub-array channels. In the Oasis montaj spreadsheet, a channel is essentially a column that contains a specific type of data. In the Oasis montaj spreadsheet, a vertical line of cells that contain data. See Oasis database A reference value to which other measurements are referred. Also, an arbitrary reference level to which measurements are corrected. For example, a datum for elevation would be sea level. Background area in the Oasis montaj project. You can open and display a virtually unlimited number of Spreadsheet, Profile and Map windows in this area.

ellipsoid

A solid figure (shaped like an egg or oval) for which every cross-section is an ellipse.

fiducials

Points accepted as fixed bases of reference. Marks indicating the order in which each reading or sample reading was taken.

Geosoft Database (GDB)

A proprietary binary database architecture that stores spatial data in a format that enables rapid access, processing and analysis of high volume data (tested up to 10 gigabytes).

Graphical Interface

Interactive software environment where functions are performed by selecting graphic objects.

grid

Collection of points along rows and columns that define a two-dimensional rectangular area on some plan, usually a ground plan.

Grids or Grid file

groups

GX or Geosoft eXecutable images or image file

line local datum transform

Files containing location (X and Y) and data (Z) values. Values are typically interpolated to create a regular and smoothly sampled representation of the locations and data. A set of graphics elements that make up a graphic component of the map. For example, a line path plot, a contour plot or a profile plot would all be separate graphics groups within the Data View. Programmed process (identified by the *.GX file extension) used to process data in Oasis montaj. Files containing location (X and Y) and Colour values. The values are not interpolated. Standard PC file types created using imaging or electronic photoediting techniques. Linear array of observation points. A datum adjusted for use in a specific location on the earth. Earth centre offset, rotation, scale factor relative to WGS 84.

Glossary 301

main window

Map (*.MAP)

map description file (*.MDF)

menu (*.OMN) Oasis montaj

Project (*.GPF)

Projection Method

random xyz data

row spheroid sub-array channels template view

Primary tool used to create and maintain databases, display data and process data. Oasis montaj is a Graphical Interface (GUI) system that provides all functionality required to process and display virtually any type of Earth Science data. Geosoft-developed file that integrates all graphics elements (lines, polygons and text) and layers (base maps, data, grids, plots and images) constructed in Oasis montaj. File used when making a standard map that has a sheet size and margins inside which there is a map area with a specified origin and scale. Usually, MDF files are created with the MAPSET GX. MDF files may also be created manually by editing an ASCII file with extension .MDF. Graphical list of commands or functions that a may choose from. Oasis montaj is the core software platform that provides all functionality required to manage, manipulate, visualize and map spatially located Earth Science data. Binary file that defines a desktop environment. It is essentially an “electronic briefcase” that helps organise data and the activities related to a data processing project. The mathematical algorithm used to transform points on a spheroid to their relative locations on a flat surface (i.e. Transverse Mercator, Lambert Conformal). Located XYZ data that cannot be grouped naturally into separate lines. For example, regional gravity surveys or geochemical surveys are commonly considered random data because the locations appear somewhat random in nature. In the Oasis montaj spreadsheet, a horizontal line of cells that contain data. A spheroid is an oblate ellipsoid of revolution (basically an ellipsoid) that is used to model the surface of the earth for the purpose of making maps. Individual channels of data from an array channel. A file used to manage data in a particular format. Stored snapshot of the screen settings, current line, displayed channels and displayed profiles in Oasis montaj.

302 Index

Index grids, 123

* *. See dummy values **. See column width

3 3D Mapping, 269 Tools, 269 Viewer, 269 Voxel, 266 3-D shading, 161

9 -9999. See dummy values

A Access. See Microsoft Access accessing online help system, 4 technical , 4 Acrobat PDF, 4 activating Image Colour Tool, 163 adding contours to maps, 124 database comments, 244 printer configuration, 251 advanced gridding, 178 mapping, 178 AGG. See Geosoft aggregate file aggregate, 136 applying formulas, 181 mask to a view, 142 ArcGIS MXD file, 44 ArcView Shapefile, 247 TIFF, 247 array channels, 312 ASCII comma delimited, 86 importing. See Microsoft Access ASCII files comma delimited, 85 editing, 169 attributes polygon, 150 Authorize Internet, 277 AutoCAD DXF, 247 Auto-Recolour

B base map control file, 168 surround, 101, 104 base maps creating, 99 custom, 168 figure style, 99 map style, 102 base view, 23, 135, 136 basic statistics, 63 batch printing, 254 processing, 173 bi-directional gridding, 113, 196 Bigrid Control File, 118 control file, 119 BIGRID GX, 113 control file, 119 dialog controls, 118 bitmap, 158, 247 Bookmark Snapshot, 125 bucket, 152

C CAD tools, 133 calculating basic statistics, 63 variogram, 199 cells channel header, 53 data, 53 CGM Plot, 247 changes discard, 80 saving database, 80 changing default settings, 37 line attributes, 146 Channel Master sample, 79 channel header cell, 53, 61, 64 channels, 312 array, 312 deleting, 70 editing, 71 hiding, 61 listing, 61 protecting, 67 spreadsheet, 20 statistics, 63 type, 88 unprotecting, 67

Index 303 working, 68 clipboard bitmap, 158 copying maps to, 157 creating montage maps, 156 EMF, 158 exporting graphics, 158 overview, 155 paste georeferenced, 156 pasting, 157 properties, 155 closing project, 47, 131, 159 colour interactive shading, 165 palette, 163 percentile groups, 165 polygon fill, 150 polygons, 152 shaded images, 161 spectrum, 165 zones, 163 colour bars plotting, 183 colour imaging interactive, 163 Colour Shading Tool, 165 colour tables for gridding, 122 coloured symbols plotting proportional size, 186 plotting simple, 184 column, 312 delimiters, 87 hiding, 61 width, 62 Comma separated value exporting, 85 importing, 86 comment header, 249 comments database, 244 compression database, 53 Computer Aided Drafting. See CAD computer ID eLicensing, 33 conditional expressions, 73 configuration printing, 250 configure printer and page, 250 configuring settings, 37 contouring methods, 124 Contouring Voxel Isosurface, 267 contours plotting, 124 control file

base map, 168 Bigrid, 119 for contouring, 124 MAPPLOT GX, 168 coordinate system datum, 211 coordinate system ellipsoid, 211 coordinate system Local Datum Transform, 211 coordinate system spheriod, 211 Coordinate system Warp, 235 coordinate systems, 211 copying from Powerpoint, 158 from Word, 158 georeferenced information, 156 maps to clipboard, 157 tutorial files, 45 creating base maps, 99, 102 channels, 69 database, 52, 178 lines from polygons, 147 map groups, 138 montage maps, 156 new channel, 68 new maps, 93 project, 46, 133 scripts, 173 working channels, 68 working directory, 45 CSV. See Comma separated value custom base maps, 168

D DAP Dapple, 276 Dapple Data, 276 Internet, 276 data cells, 53 comma delimited, 86 correlation, 199 displaying, 61 dynamic data links, 167 geochemical, 116, 178 gridding, 113, 203 gridding random, 115 importing, 58, 84, 178 importing for kriging, 198 interpolating, 75 plotting, 204 plotting profiles, 105 processing, 63, 181 range to map, 94 selecting, 92 semivariance, 199 spikes, 73 statistical, 116 Data

304 Index Dapple, 276 data channel, 186 Data Import Wizard, 86, 87, 88 data values, 184 posting on map, 185 data view, 23, 135, 136 database, 312 adding comments, 244 applying formulas, 181 channels, 53 compression, 53 creating, 52 creating second, 178 details, 243 drag-n-drop, 60, 90 editing, 71 exporting, 82 fields, 53 Geosoft, 18 groups, 53 importing data, 58 indivdual table, 82 lines, 53, 61 maintenance utilities, 243 Oasis, 18 proprietary, 18 relational, 18 saving changes, 61 single table, 83 size, 53 size limits, 244 database elements, 244 databases creating, 84 defragmenting, 244 discard changes, 80 growing, 244 importing, 84 importing tables, 84 packing. See defragmenting repairing, 244 saving changes, 80 ing, 244 datum, 312 Dbase, 81 default colour table, 38 error level reporting, 40 grid element type, 39 grid input fromat, 39 grid output fromat, 39 map font, 38 menus, 38, 48 settings, 37 symbol colour table, 38 Default settings SETTINGS GX, 38 default.i0, 60, 180 define x,y coordinate systems, 213 defining coordinate system, 213 defragmenting

database, 244 deleting channels, 70 delimited comma, 86 desktop, 312 details database, 243 dialog controls Bigrid, 118 discard changes, 80 disk space, 244 displaying grids, 122 interpretation map, 134 profile, 65 spreadsheet data, 61 drag-n-drop database, 90 grid, 124 xyz, 60 drawing base map, 99 map groups, 136 polylines, 143 symbols, 184 dummy values, 60 including in export, 249 interpolating, 75 DXF AutoCAD, 247 dynamic data links, 167 linking, 161 links, 11, 24, 27 process link, 30

E edge symbol colour, 184 editing ASCII files, 169 channels, 71 groups, 136, 139 legend boxes, 149 maps, 133 polygons, 149 scripts, 175 eLicense Park, 35 Transfer, 36 Update, 37 eLicenses Lock/Unlock, 37 Upgrade, 35 eLicensing, 33 Licensing management system, 33 ellipsoid, 312 Encapsulated Post Script, 247 Enhanced Metafile, 247 Enhanced Windows Metafile, 155, 157

Index 305 equal zoning, 163 ER Mapper ECW Compressor, 247 ER Mapper RGB, 247 error level reporting default, 40 Excel. See Microsoft Excel Explorer tools Tools, 13 export formats, 81 exporting graphics, 158 individual tables, 82 maps, 247 Microsoft Access, 82 single table, 83 to CSV file, 85 to database applications, 248 to GIS applications, 248 to spreadsheet applications, 248 expressions conditional, 73 eyedropper, 152

F fiducial, 71 fiducials, 312 figure style base maps, 99 file types .AGG, 44, 184 .CSV, 85, 86 .EMF, 155, 157 .GDB, 44 .Geosoft_Voxel, 44 .GI, 45 .GM, 45 .GPF, 45 .GRD, 44 .GS, 44, 173 .GX, 44 .ITR, 184 .MAP, 44 .MDB, 84 .MDG. See Microsoft Access .MXD, 44 .OMN, 44 .SMN, 44 .TBL, 184 .XML, 44 .ZON, 184 ASCII. See Microsoft Access files for tutorial, 45 fill patterns, 150 symbol colour, 184 filling polygons, 152 filling gaps using interpolation, 75

flight lines plotting, 104 formulas applying to database, 181 FoxPro, 81 full map, 110, 248

G gaps filling, 75 Gaussian value, 199 gdb drag-n-drop, 90 GDB. See Geosoft database file geochemical data, 116, 178 gridding, 196 georeference connections, 166 georeferenced objects pasting, 156 Geosoft aggregate file, 44, 184 colour zone file, 184 database file, 44 grid file, 44 image transform file, 184 map file, 44, 45 menu file, 44 project file, 45, 46 projection file, 45 Script file, 44 sub-menu file, 44 table file, 184 XML file, 44 XYZ files, 58 Geosoft Colour Grid, 247 Geosoft coordinate systems, 212 Geosoft eXecutables, 44, 312 description, 29 Geosoft plot file, 247 Geosoft script files. See scripts Geosoft_Voxel. See Geosoft_Voxel file GeoTIFF, 247 Get Colour tool, 152 GI. See Geosoft projection file GM. See Geosoft map file GPF. See Geosoft project file Graphical Interface, 312 graphics exporting, 158 high-resolution, 37 grd drag-n-drop, 124 GRD. See Geosoft Grid file grid, 312 creating new, 120 drag-n-drop, 124 grid coordinate system, 225 grid element type default, 39

306 Index grid file. See Geosoft Grid file grid image exporting, 158 grid input format default, 39 grid output format default, 39 gridding, 91 advanced, 178 bi-directional, 113, 196 data, 113, 203 description, 113 dialog, 118 dialog controls, 119 displaying grids on maps, 122 kriging, 197 krigrid, 115 minimum curvature, 114, 194 random, 196 random data, 194 tinning, 197 trend-enforced, 117 using colour tables, 122 Gridding Voxel, 266 grids, 312 colour shaded, 161 contouring, 124 displaying, 122 Grids recolour, 123 groups, 312 copying, 156 creating new, 138 definition, 23 editing, 136, 139 hiding, 140 in maps, 23 in spreadsheet, 20 masking, 141, 142 moving, 141 on map, 136 pasting georeferenced, 156 selecting, 136, 139 growing databases, 244 GS, 173, See Geosoft script file file GX. See also Geosoft eXecutables dialog box, 29 GX Developer, 29 GXs BIGRID, 113, 118, 119 KRIGRID, 115 MAPPLOT, 168, 169, 171 RANGRID, 115, 194

H header cell, 61 help accessing online, 48, 50 hiding

channels, 61 groups, 140 high-resolution graphics, 37

I Image Colour tool, 163 images colour shaded, 161 images or image file, 312 imaging, 161 interactive colour, 163 interactive colour shading, 165 import formats, 81 import template, 60 importing ASCII data, 81 data, 58 data for kriging, 198 database tables, 84 databases, 84 Excel data, 81 from CSV file, 86 into second database, 178 XYZ data, 178 XYZ files, 58 indentifying linear features, 143 Install , 34 eLicense, 33, 34 Installing Oasis montaj, 34 interactive colour imaging, 163 colour shading, 165 shadowing, 163 Internet communications, 277 connectivity, 277 interpolating data, 75 interpretation map displaying, 134 Isosurface 3D contour, 267

J JPEG, 247

K kriging, 115, 197 overview, 197 krigrid plotting data, 204 KRIGRID GX, 115

Index 307

L last map view, 110 layers moving, 136 on map, 136 legend ternary colour, 209 legend boxes editing, 149 legend symbols, 193 legends plotting, 183 Line Command Toolbar, 67 line path plotting, 104 Line Selection Tool, 93 linear features indentifying, 143 linear zoning, 163 lines, 312 changing attributes, 146 creating polygons from, 147 database maximum, 53 non-parallel, 115 on map, 136 plotting survey, 104 polylines. See polylines selecting, 67, 92 selecting by range, 93 snapping to, 145 linking, 161 data, 27 data points, 167 dynamic, 27 objects, 27 links dynamic process, 30 list channels, 61 loading menus, 48 local datum transform, 312 log contour, 124 log10, 181

M main window, 313 maintenance database, 243 maker, 30 manuals accessing online, 48, 50 printing, 51 map. See also maps Map Base view, 23 creating, 93 Data view, 23 default font, 38

description file, 313 description of, 23 full, 110 groups, 23 last view, 110 navigating, 107 object, 136 origin, 157 panning, 109 redraw, 110 shrink, 110 Snapshot, 125 surround, 135 templates, 93, 97 views, 23 zooming, 108 MAP. See maps Map (*.MAP), 313 map coordinate systems, 211 map style base maps, 102 Map view coordinate system, 229 MapInfo TAB, 247 MapInfo TIFF, 247 mapping, 91 advanced, 178 selecting data for, 92 tools, 133 Mapping 3D, 269 MAPPLOT GX, 168, 169 control file, 168, 171 maps adding contours, 124 adding grids, 122 adding profiles, 105 adding survey lines, 168 base map, 99, 168 base view, 135 batch printing, 254 clipboard, 155 creating groups, 138 data view, 135 editing, 133 exporting, 247 exporting graphics, 158 function, 135 groups, 136 interpretion, 134 linking data, 167 montage, 157 offset, 157 opening, 134 parts of, 135 pasting georeferenced, 156 pasting graphics, 158 print preview, 252 printing, 247, 250, 253 scale, 157 shaded relief, 161 mark statistics, 63

308 Index masking apply to view, 142 groups, 141, 142 rectangular, 141 math formula tool, 73 new channel, 69 maximum groups, 53 lines, 53 value, 65 MDB files. See Microsoft Access menu, 313 menus loading, 48 setting default, 48 Metadata Tool, 279 viewing data, 279 Microsoft Access, 81, 83, 84 database file, 84 exporting to, 82 Microsoft Excel exporting to, 85 importing from, 86 minimum curvature gridding, 114, 194 interpolation method, 76 montage maps using clipboard, 157 moving groups, 141 multiple coordinate systems on map, 235 MXD. See ArcGIS MXD file

N navigating map, 107 new channel, 69 database, 53, 84, 178 group, 138 project, 133 new channel, 68 normal zoning, 163 north arrow, 23, 99, 135 nugget, 201

O Oasis database. See database Oasis montaj, 313 default settings, 38 integrated environment, 9 Mapping and Processing System, 7 starting, 43 Viewer, 7 oasis.omn, 48 object maker, 30 objects

pasting georefenced, 156 ODBC. See Open Database Connectivity offset, 157 OMN. See Geosoft menu file online help accessing, 4 Manuals, 48, 50 Technical notes, 48, 50 Tutorials, 48, 50 opening maps, 134 project, 161 output format, 248

P packing databases. See defragmenting panning map, 109 Paradox, 81 parameters variogram, 201 pasting georeferenced groups, 156 on map, 158 patterns copying, 152 polygon fill, 150 PCX, 247 PDF Acrobat file, 4, 51 percentile groups colour, 165 plotting. See printing colour bars, 183 contours, 124 krigrid data, 204 legend symbols, 193 legends, 183 profiles, 105 proportional coloured symbols, 186 range classified symbols, 190 simple coloured symbols, 184 survey lines, 104 symbols, 183 zone coloured symbols, 188 PNG, 247 points snapping to, 145 Polygon Fill tool, 152 polygons creating from lines, 147 editing, 149 fill patterns, 150 polylines drawing, 143 poster using clipboard, 157 posting data values, 184, 185 power value, 199 Powerpoint. See Microsoft Powerpoint previewing printing, 252

Index 309 printer drivers, 250 printing batch, 254 configuration, 250 maps, 247, 250, 253 online tutorials, 51 options Geosoft bands, 250 Geosoft bands and dither, 250 HP-RTL, 250 previewing, 252 setup, 250 processing data, 63, 181 selecting data for, 92 using scripts, 173 processing speed, 53 profile view, 71 profile window, 22, 65 profiles, 22 displaying, 65 linking data, 167 options, 66, 77 plotting, 105 scale, 66, 77 variables, 22 project closing, 47, 131, 159 creating, 46, 133 opening, 161 saving, 47, 131, 158 Project, 12 project coordinate, 214 Project Explorer, 12 projected long,lat, 221 projected x,y, 215 projecting data, 211 projection method, 313 Projection method, 211 Projects *.gpf files, 13 proportional size symbols, 184, 186 protecting channels, 67

Q quick contour, 124

R random gridding, 196 random data gridding, 194 random xyz data, 313 range classified symbols, 184 range/slope, 201 RANGRID GX, 115, 194 recolour

grids, 123 recording scripts, 173 rectangular mask, 141 redraw map, 110 relief image, 161 rendering map groups, 136 order, 23 repairing databases, 244 resolution map, 157 rows, 20, 313 running scripts, 177

S sample interval, 21 saving databases, 80 project, 47, 131, 159 scale bar, 23, 98, 99, 135 scaling profile windows, 66, 77 Script file, 44 scripts, 173 creating, 173 editing, 175 recording, 173 running, 177 sample file, 175 second database, 178 selecting current view, 156, 157, 158 data, 92 groups, 136, 139 lines, 93 variogram model, 201, 202 semivariance, 199 semi-variogram. See variogram setini, 175 setting default menus, 48 settings configuring, 37 default, 37 setup printing, 250 shaded images, 161 shadowing interactive, 163 show profile, 65, 71 shrink map, 110 sill, 201 size database, 53 SMN. See Geosoft sub-menu file Snap to line, 145

310 Index Snap to point, 145 snapping mode, 157 Snapshot bookmark, 125 Map, 125 spectrum colour, 165 speed, 53 spherical model nugget, 201 spherical value, 199 spheroid, 313 spikes removing, 73 spreadsheet, 20 column width, 62 columns. See channels components, 20 description, 52, 61 displaying data, 61 linking data, 167 processing data, 181 view, 20, 61 window, 20, 66, 70, 182 statistics channel, 63 marking, 63 report, 63 saving, 64 sub-array channels, 313 survey lines parallel, 113 plotting, 105 tie, 113 surveys plotting lines, 104 symbol colour table default, 38 symbols colour legend bars, 184 horizontal colour legend bars, 184 legend, 184, 193 plotting, 183 proportional size, 184, 186 range classified, 184, 190 zone coloured, 184, 188

T template, 313 map layout, 97 xyz import, 60 ternary colour legend, 209 tie lines gridding, 113 TIFF, 247 TIFF Compressed, 247 tinning, 197 Tool Metadata Browser, 279

trend-enforced gridding, 117 tutorial files list, 45 tutorials accessing online, 48, 50 printing, 51

U unprotecting channels, 67 utilities database maintenance, 243

V value dummy, 60 variogram calculating, 199 parameters, 201 selecting model, 201 spherical model, 201 variogram model selecting, 202 variograms, 197 calculating, 199 displaying, 199 ing databases, 244 view, 313 View/Group Manager, 139 View/Group Manager Tool, 136 viewed region, 248 Viewing Metadata, 279 views applying a mask, 142 base, 135 changing, 157 copying, 156 data, 135 pasting, 156 Visual Basic, 29 Voxel *.Geosoft_Voxel file, 44 3D Grid, 266 3D Kriging, 266 Isosurface, 267

W Warp Coordinate system, 235 Warp Image file, 238 Windows clipboard, 155 printer driver, 250 working channels creating, 68 working directory creating, 45

Index 311

X XML. See Geosoft XML file xyz drag-n-drop, 60 XYZ data importing, 58, 178

Z zone colour symbols, 184, 188 zoning, 163 data, 163 zooming map, 108

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