Discover 3D Training Manual

Table of Contents

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Table of Contents Con tents 1

Introduction.. Introduction .............................................................................................. ............................................................................................1

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Discover 3D Data Formats.. Formats ...................................................................... ....................................................................3 3

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Discover 3D Menu in the 2D Environment .. ............................................ ..........................................7 7

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Discover 3D Interface I nterface.. .............................................................................. ............................................................................9 9 The 3D Interface........................................................................................ Interface........................................................................................9 9 Navigating in 3D ...................................................................................... ......................................................................................10 10 Exaggerating Exaggerating the scale ............................................................................ ............................................................................12 12 View Modes... Modes ............................................................................................. ..........................................................................................12 12 Menus...................................................................................................... Menus... ...................................................................................................13 13 Workspace Tree ...................................................................................... ......................................................................................13 13 Inserting datasets .................................................................................... ....................................................................................16 16 3D Session Session File File ....................................................................................... .......................................................................................16 16 Properties Properties Dialogs Dialogs ................................................................................... ...................................................................................16 16 Display 3D Axes Axes ...................................................................................... ......................................................................................18 18 3D Cursor Plane...................................................................................... Plane... ...................................................................................19 19 Feature Toolbar Toolbar... ....................................................................................... ....................................................................................20 20

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3D Raster Images ... .................................................................................. ...............................................................................23 23 View Map Map in 3D 3D ....................................................................................... .......................................................................................23 23 3D Display Wizard................................................................................... Wizard...................................................................................24 24 Overlay Image Image on Grid ............................................................................ ... .........................................................................25 25 Insert Image directly into 3D.................................................................... 3D... .................................................................25 25 Georeferencing Georeferencing Wizard ........................................................................... ... ........................................................................26 26 Multi Section Creator............................................................................... Creator... ............................................................................26 26

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View Vector Data as 3D DXFs ... .............................................................. ...........................................................29 29 Import 3D Vector Vector File .............................................................................. ..............................................................................29 29 Import Objects from Table or Selection................................................... Selection... ................................................30 30 Creating 3D Extrusions Extrusions ........................................................................... ...........................................................................31 31

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View 3D Point and Line Data ... ................................................................ .............................................................33 33 View 3D 3D Point Data ................................................................................. .................................................................................33 33 View 3D Line Data................................................................................... Data...................................................................................35 35

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Gridded Surfaces ... .................................................................................. ...............................................................................37 37 What is a Surface Surface Grid? .......................................................................... ..........................................................................37 37 Configuring Configuring Grid File Formats Formats ................................................................. ... ..............................................................39 39 Create Surface Grid ................................................................................ ... .............................................................................40 40 Input Input Tab ............................................................................................ ............................................................................................41 41 Modify Grid Appearance.......................................................................... Appearance... .......................................................................43 43 Assign Grid Values to Vector Vector Layers ...................................................... ......................................................45 45 Surface Profile over a Grid or Contour Plan... ......................................... 46 Contouring Contouring a Grid File File ............................................................................. ... ..........................................................................48 48 Grid Query Query using Multiple Ranges Ranges .......................................................... ... .......................................................49 49 Convert Grid to New Grid Format............................................................ Format... .........................................................51 51 Importing a Grid Surface Surface ......................................................................... .........................................................................51 51 Clip Grid................................................................................................... Grid...................................................................................................52 52

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Encom Discover 3D Workshop Manual

Reproject Reproject Grid .......................................................................................... ..........................................................................................54 54 Gridding Geochemical Geochemical Data ..................................................................... ... ..................................................................54 54 Inverse Distance Distance Weighting Weighting ................................................................ ................................................................58 58 Kriging Kriging ................................................................................................. .................................................................................................61 61 Grid Calculat Calculator or ......................................................................................... .........................................................................................61 61 Gridding Geophysical Data ...................................................................... ... ...................................................................63 63 Filtering a Surface Surface .................................................................................... ....................................................................................64 64 List of Available Grid Utilities.................................................................... Utilities... .................................................................65 65 Displaying Surfaces Surfaces in 3D ........................................................................ ........................................................................66 66

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2D Drillholes ... ........................................................................................... ........................................................................................71 Introduction............................................................................................... Introduction...............................................................................................71 71 Steps to Create Create Drillhole Sections ........................................................... ...........................................................72 72 Drillhole Data Format ............................................................................... ...............................................................................73 73 Collar Table......................................................................................... Table.........................................................................................73 73 Downhole Survey Survey Table ...................................................................... ......................................................................73 73 Downhole Data Tables........................................................................ Tables........................................................................74 74 Create Drillhole Project ............................................................................ ............................................................................75 75 Data Validation Validation... ......................................................................................... ......................................................................................77 77 Create Drillhole Sections and Plans......................................................... Plans... ......................................................79 79 Display Downhole Data on Section.......................................................... Section... .......................................................82 82 Create Drillhole Drillhole Colour Pattern Pattern ................................................................ ... .............................................................84 84 Using the Drillhole Section Manager... ..................................................... .....................................................86 86 Adding a Drillhole Drillhole Section to a Layout Layout ..................................................... ... ..................................................88 88 Extracting Maximum Maximum and EOH Assay Values Values for a Drillhole .............. ..............89 89 Drillhole Log Display................................................................................. Display.................................................................................90 90 Digitizing Boundaries Boundaries and Exporting Exporting to 3D DXF ...................................... ... ...................................92 92 Calculating Sectional Resources ............................................................. .............................................................93 93 Data Compositing..................................................................................... Compositing.....................................................................................94 94 Compositing by Unique Unique Attribute ........................................................ ........................................................95 95 Compositing by Cut-off Grade............................................................. Grade... ..........................................................96 96 Compositing by Elevation and Downhole Depth................................. Depth... ..............................96 96 Calculate 3D 3D Coordinates Coordinates ........................................................................ ........................................................................96 96 Drillhole Project Management Management .................................................................. ... ...............................................................96 96

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3D Drillholes ... ........................................................................................... ........................................................................................97 Drillholes................................................................................................... Drillholes...................................................................................................97 97 Drillhole Sections...................................................................................... Sections......................................................................................99 99 Drillhole Logs......................................................................................... Logs.........................................................................................100 100 Drillhole Selections................................................................................ Selections................................................................................101 101 Display Downhole Data......................................................................... Data.........................................................................101 101 Section Boundaries Boundaries ............................................................................... ...............................................................................107 107

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Voxel/Block Models.... Models............................................................................. .........................................................................109 109 Opening a Voxel Model Model.... ......................................................................... .....................................................................109 109 Voxel display options............................................................................. options.............................................................................110 110 Import and Export of Voxel models models ....................................................... .... ................................................... 112 Creating a Voxel model model ......................................................................... .........................................................................113 113 Examining the data distribution distribution ........................................................ ........................................................ 114 Gridding numeric numeric data ...................................................................... .... ..................................................................115 115 Gridding geological geological data .................................................................. .... ..............................................................117 117

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3D Digitization Digitizati on and Solid Generation .... ................................................ ............................................119 119 Digitization............................................................................................. Digitization.............................................................................................120 120 Feature editing 121





































Table of Contents

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Movie Making .... ....................................................................................... ...................................................................................125 125 3D Fly-Through Fly-Through Animation .................................................................... .... ................................................................125 125 How Fly-Through Fly-Through Animation Animation Works ................................................. .... .............................................125 125 Create 3D Fly-Through File................................................................... File.... ...............................................................127 127 General Playback Options ............................................................... ...............................................................128 128 Add capture points and event event details details ............................................... .... ........................................... 129 Output Output Formats Formats ................................................................................ ................................................................................131 131

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3D Printing and Output Options .... ........................................................ ....................................................133 133 Print Directly from from Discover 3D 3D ............................................................. .............................................................133 133 Export 3D View as Raster Image Image .......................................................... ..........................................................134 134 Add 3D View to MapInfo........................................................................ MapInfo........................................................................134 134 Save to Packag Package e ................................................................................... ...................................................................................134 134 3D Workspace Workspace File ................................................................................ ................................................................................135 135

Appendix A Menus and Toolbars.... Toolbars ................................................................. .............................................................137 137 File Menu............................................................................................... Menu...............................................................................................137 137 View Menu............................................................................................. Menu.............................................................................................138 138 Insert Menu............................................................................................ Menu............................................................................................138 138 Tools Menu............................................................................................ Menu............................................................................................139 139 Utilities Menu......................................................................................... Menu.........................................................................................140 140 Main Toolbar.......................................................................................... Toolbar.... ......................................................................................141 141 Data Objects Toolbar ............................................................................ ............................................................................141 141

Workshop Notes .... ............................................................................................ ........................................................................................143 143









































































Introduction

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Introduction Encom Discover 3D is a separate add-on module designed to work seamlessly with Encom Discover. The module is automatically disabled in the Discover menu unless the Discover 3D module has been purchased. Surfaces representing topography, geochemistry and geophysics, drillhole sections containing assays or lithological data or any other mapped data combinations created using MapInfo/Discover can be transferred to the Discover 3D interactive three-dimensional environment. Additional objects such as 3D DXFs, grid surfaces and raster images plus point and line data can be added to the 3D displays from MapInfo or independently. Discover 3D enables data to be viewed interactively with zooming, panning and flythrough capability. capability. View orientations can also be taken from Discover 3D back into MapInfo and displayed in a layout for presentation purposes. Discover 3D operates seamlessly seamlessly with Encom Discover. If you know how to create a map, a drillhole project and sections in Discover, this is all you need to operate Discover 3D. No additional project specification or data setup is required since the displays within MapInfo, created by Discover, are passed directly to Discover 3D for presentation and interactive use. The Discover 3D display below is typical of the type of displays derived from various data types.

Complex view with surface, drillholes and 3D objects displayed











































































Discover 3D Data Formats

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Discover 3D Data Formats The Discover 3D module comprises both a Discover 3D menu within the 2D/MapInfo interface, interface, as well as its own separate 3D interface/window. interface/window. These allow a 3D display to be created both from datasets already open within 2D MapInfo/Discover interface, and/or by opening applicable data directly into the 3D window. This allows a large range of data formats to be created and supported by Discover 3D.

Images The content of any map window open within MapInfo/Discover can be displayed within the 3D environment as a geo-located image, using the View Map in 3D menu option. This produces a .PNG image with an accompanying .EGB file (georeferencing (georeferencing header file). All data sets visible in the map window (e.g. grids, images, vector data) will be incorporated into the image. The image’s RL can be assigned manually, or it can be ‘draped’ over a gridded surface (e.g. a DEM grid). Drillhole sections and Drillhole Logs can also be displayed as images using the View Sections and View Logs options. Images can also be directly opened and georeferenced in the 3D window, using the Georeferenced Image Creation Wizard. This wizard supports .BMP, .PNG, .TIF, .GIF and .JPG image formats. Images with an existing .EGB file can also be opened directly from within the 3D window. A lot of data can can be easily displayed displayed in 3D as as an image, image, but the data cannot be modified or interrogated.

DXF/Vector Objects MapInfo vector data such as points, lines and polygons can be displayed in Discover 3D as DXF files. The View Objects in 3D menu option allows any vector dataset open in MapInfo to be converted into a DXF file and placed into the 3D environment. This could include infrastructure (roads), contour lines (created from a gridded surface using the Surfaces>Contour a Grid menu option) or orebody boundaries interpreted on drillhole cross sections (display in 3D using the View Section Boundary option). Existing DXF files (eg the output from modelling programs) can be opened directly into Discover 3D via a number of menu options, or by simply dragging and dropping the DXF from Windows Explorer. DXF’s are a very efficient way of displaying a large amount of vector data, particularly points and polylines; however they have limited display options.





































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Displaying flight lines coloured by date.

Displaying data in 3D as Points or Lines therefore gives the user a great deal of display control and options; however instigating these options on large datasets can severely affect 3D rendering performance.

Gridded Surfaces Grids created using either the Discover>Surfaces menu or other products (eg topographic topographic or geochemical surfaces in formats such as Geosoft, ER Mapper, Surfer etc.) can displayed in Discover 3D either directly or via the View Surface in 3D menu option. A large range of grid types are supported. Support is also provided for the draping of ER Mapper ECW and .ALG files.

Drillholes Drillholes present in an open Discover Drillhole Project can be displayed in Discover 3D using the View Drillholes menu option. Alternatively, the relevant collar, survey and downhole data .TAB files can be opened directly into Discover 3D if they are assigned to a Discover Drillhole Project. The display of 3D drillholes can be modified by colour and thickness modulation, as well as labelling and annotation options. Images of cross-sections and drillhole logs created in Discover can also be displayed in 3D. Interpretative linework digitized into cross-sections can be exported into 3D as DXF objects. Discover 3D can also directly open Geosoft drillhole databases (usually with a suffix .GDB).

Drillhole Selections A selection from from a drillhole drillhole project (eg (eg all downhole downhole intervals with Au>50ppb Au>50ppb in a subset of drillholes) can be displayed as a DXF file in Discover 3D.

Voxel Models Discover 3D can create, display and manipulate Voxel block models (eg IP resistivity), supporting formats formats such as UBC, CEMI, and Noddy, as well as preliminary support for Datamine, Surpac, Vulcan and Gocad Voxet.

Feature Database Points, polylines and polygons can be digitized and attributed directly into the 3D environment as part of a Feature Database. Additionally, dxf vector or MapInfo





































Discover 3D Data Formats

Movies and Fly-Throughs The Fly-Though Wizard allows the creation of both Encom .FLY files for reuse within the 3D environment, as well as .AVI movie files.

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Discover 3D Menu in the 2D Environment

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Discover 3D Menu in the 2D Environment To open the Discover 3D menu in the 2D MapInfo/Discover interface select Discover>Discover 3D. This will place a Discover 3D option on the MapInfo Professional menu bar.

Discover 3D Menu Options

The Discover 3D menu allows a range of data types open within the MapInfo/Discover environment to be displayed in the 3D environment. It contains the following f unctionality: unctionality: •

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Open 3D Window - Open Discover 3D program from MapInfo/Discover Open/Save 3D Workspace - Open or save 3D Workspace. A 3D workspace saves the current MapInfo and Discover 3D session into a single workspace file. Refresh All 3D Data – Update data in MapInfo/Discover and send changes through to Discover 3D without having to close down. View Map in 3D – Display a MapInfo map window view as a georeferenced 3D bitmap image.







































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View Drillholes - Display drillholes in 3D. This option loads the entire drillhole dataset. View Sections - Display drillhole sections as georeferenced 3D bitmap images. View Logs - Display drillhole logs as georeferenced 3D bitmap images. View Section Boundary – Display section orebody or lithological boundaries boundaries as 3D DXF vector files. View Drillhole Selection - Display only selected drillholes in 3D. This option does not load the entire drillhole dataset. 3D Display Wizard – Display an entire map window view or objects from a table through an easy-to-use wizard interface. 3D Extrusion Wizard - Extrude 2D bodies in 3D to aid in visualisation of fault planes, veins or mine infrastructure. 3D Utilities – Use the Multi Section Generator to register multiple images as sections using a series of lines or points. Use the Overlay Image on Grid to drape a raster image over a gridded surface using the original raster resolution. Toggle Auto 3D Selection - Turn the Auto 3D selection option On or Off. Options – Various user-defined system and display settings to customise Discover 3D such as temporary directory directory location, surface display and compression options, XYZ indicator, map projection, images resolution, etc.





































Discover 3D Interface

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The main screen items of Discover 3D

To open the Discover 3D window, select the Discover 3D>Open 3D Window menu option from the Discover 3D menu in the 2D MapInfo interface. The 3D window will open after a short time. Alternatively, the Discover 3D window window can be accessed accessed when a mappable mappable MapInfo





































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The Workspace Tree on the left of the display window may appear as a separate window or it can be placed or docked where convenient. This tree provides a hierarchy view of all objects, data sources and controls of t he various displays. Workspace Tree contents alter when a dataset is accessed or a window is highlighted. The Workspace Tree can be removed from view and restored using the button shown left. It can be re-docked by double clicking on the title bar. The Interactive Help (called iHelp) may appear as a separate window or it can be placed or docked where convenient. This sheet provides online assistance for whatever display option is being used. The Interactive Help can be removed from view and restored using the button shown left. It can be re-docked by double clicking on the title bar.

Navigating in 3D Discover 3D has two modes for controlling for navigation and specifying view positions and movement, available through the following buttons:

Exercise 4.1

Manoeuvre within the 3D environment.

Data Location:

Encom Training\Training Training\Tr aining 3D\Structure

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From within Windows File Explorer, navigate to the above directory, and drag and drop the Interp_Structures_all_3D_iso.dxf into the 3D window.

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Experiment Experiment with the controls as detailed below.

The Navigate button is used generally to make windows active, control the 3D






































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Right mouse button with vertical movement zooms the image in or out of the display. The numeric keys (1-0) can be used to control the zoom speed, with 1 & 2 applying the slowest zoom speeds and 9 & 0 the fastest. Left and Right buttons depressed with cursor movement allows positioning of the view point in the X/Y plane. Moving the cursor horizontally pans the view (moving the view point left/right), whilst moving the cursor vertically moves the view point in a ‘fly-through’ operation. Keyboard entries with mouse manipulation can also be used to control 3D display operation. Available combinations include:

SHIFT key plus pressed left mouse button repositions the view point in the vertical axis and screen plane (this only operates in Navigate 3D mode). Holding the cursor near the view point reduces the speed of panning. CTRL key plus pressed left mouse button repositions/rotates the image view whilst maintaining the current current eye position. Nearer the centre of the view reduces the speed of panning.

Reset 3D View restores the 3D display to a default such that the first displayed object is centred and shown within the window. The Page Layout buttons are designed for use mainly within the Page Layout view. The Zoom In and Zoom Out controls allow adjustment of the overall zoom ratio of the page display, whilst the Pan button enables you to position the cursor in a display window and roam the view. These can be used within the 3D View, but the 3D Navigation control is recommended. The Fit to Page button is only available in Page Layout view, and automatically resizes the page to fit to the extents of the view.

Note

If you have a mouse with an ‘active’ wheel, you can also use this for zoom operations. This is only recommended for use in controlling the Page Layout





































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Exaggerating the scale

Bounding Box dialog

For Global scaling changes, the 3D Map Properties dialog contains options including: •

Add a title to the map window in Page Layout mode

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Display a bounding box around the 3D data in the map window








































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the placement of objects prior to printing. The size and orientation of the page is defined by printer settings specified in the File>Page Setup option You may switch between Normal and Layout views quickly by using the Page Layout button or from the Window menu option.

Menus Discover 3D contains the following pull-down menus; most of the menu functionality is duplicated in the related Toolbars : •

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File - File handling for project sessions and access to external databases is controlled using the options on this menu item. Setting of printing and exiting are also available. View - Options to display the various view modes, toolbars and control dialogs, status bar and property dialogs. Insert – Permits graphical objects to be inserted into existing 3D map window displays. These menu commands are also duplicated on the Data Object toolbar. and Export of vectors vectors in feature databases databases including DXF Features – Import and





































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Each branch of the tree is subordinate to a higher branch in the hierarchy such that control properties of a higher branch overrule the same properties of a lower branch when they occur. The Workspace Tree grows incrementally as various objects are added or changed. To the left of each subordinate branch is a small or box. These boxes indicate lower levels exist for that branch. By clicking on these boxes you can expand their content as shown here for the previous tree. When this is done, additional control branches and data sources appear. The icons to the left of each branch control control the visibility, editability, and selectablilty of each layer as the same as in the Discover Enhanced Layer Control window .






































Right mouse button control on

Menu display

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Options available

3D Map Branch Display properties of the 3D Map or any subordinate branches. Add axes or add additional data objects such as drillholes, raster images etc. Open the Fly-through Wizard.

Data Object Branch Properties and Delete options are available.

Surface Branch





































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Inserting datasets •

Data Objects – allows addition of various data types to 3D view.

3D Session File Sessions and project management is controlled by the File>Open Session, Save Session and Save Session As items. Discover 3D uses binary session files to save and restore projects. Within the session files the following information is stored: •

Path(s) to the necessary data source information.

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Path(s) to any used object, raster and bitmap files.

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Path(s) to drillhole databases.

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Configuration data for open windows and components, their attributes and properties.






































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Selecting any branch in the workspace tree and click the right mouse button. The Properties menu item accesses the relevant Properties dialog. Double click the relevant item in the Workspace Tree with the left mouse button. Select the Workspace Tree branch and then click the Properties button.

In most cases, the Properties dialog has tabs displayed at the top. Each tab controls a separate aspect of the item selected.







































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Show/Hide box. Turning off the visibility for an object branch will also turn off the visibility of any sub-branches.

Display 3D Axes Three dimensional displays are powerful tools that assist the understanding of the positions of such things as drillholes, sections, geological features, etc; but they require a clear understanding of their location both in easting/northing and depth. Discover 3D allows you to add axes in 3D displays to locate such features. Select the Insert>3D Axis menu option. The primary axes (East – X, North –Y and Depth – Z are drawn into the display.






































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3D Cursor Plane

The 3D Cursor Plane mode allows the user to identify the 3D coordinates of any point in the 3D window. Clicking the Show 3D Cursor Plane button will display the default Cursor Plane location surrounded by a bounding Focus Box.





































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The orientation of the cursor plane can be controlled via the options below. Up / Down (↑↓) keyboard cursor /arrow keys Left / Right ( ← →) keyboard cursor /arrow keys

Controls the dip of the cursor plane (rotates it about a line located in the XY plane) Controls the azimuth of the cursor plane (dip is constant)

PageUp / PageDown Shifts the cursor plane laterally (plane is kept parallel to but shifted left or right (or up or down) from it’s current position, maintaining dip and azimuth) keyboard buttons Switches the cursor plane between the X, Y and Z planes.






































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A Feature database (cosmetic or created) must be editable for the Feature toolbar to be enabled. The following controls are available:

Confirm New Feature - Option to display a dialog after each feature object is created to enable input of attribute data. Select Feature - Create a selection region to select all Feature Objects that intersect or lie within this region. This selection region is independent of the Cursor Plane. It is drawn in the screen plane and will select all objects below it. The selected object attributes are listed in the Data tab of the Information Sheet. The Select/Navigate mode on the Zoom Controls Toolbar can also be used





































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Snap to node – Allows the current object’s node (new object or editing an existing object) to be snapped to an existing object’s node. Upon activation, the cursor will change to a circle in the middle of the cross-hairs; when the cursor is close to an existing node, it will change to the standard cross hair; left click to snap to this node. To the right of the Snap toolbar button is a pull-down options dialog. This allows the Pixel Tolerance to be set (i.e. how close the cursor needs to be to an existing node before it can be snapped to that node). A high-pitched audible Beep (dee ) can also be enabled for when the cursor is within the set pixel tolerance, when the cursor moves outside the tolerance, a low pitched doh will sound. The Duration of these beeps can be set in milliseconds.







































3D Raster Images

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3D Raster Images

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To navigate around the 3D display, click the 3D Navigation button in the toolbar. Hold down the left mouse button and move the mouse to rotate the view about the viewing centroid. Hold down the right mouse button and





































3D Raster Images

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3D Raster Images

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Bivariate View The Bivariate view requires the user to define two input or key fields. In this instance a Scattergram is displayed in the Graph page for both key fields plotted against each other. A linear regression line is displayed as a blue line with a conditional expectation curve displayed as a green line. A purple quantile vs. quantile curve line from 5%-95% is also displayed. The statistics page presents summary statistics for the bivariate distribution as well as spreadsheet for the conditional expectation.

Variogram The Variogram view requires the user to define a key field which will be used in tandem with the spatial coordinates to compute a sample variogram. A variogram shows the degree of correlation between data in a spatial dataset in different directions and at different distances. If Kriging has been used as the interpolation method then a Model Variogram can also be created, edited and displayed. See the Discover Reference manual or On-line Help for more information on working with Kriging and Variograms . 12.

Click Cancel to exit the Statistics Explorer .

Inverse Distance Weighting Inverse Distance Weighting uses weighted average interpolation to estimate grid cell values and can be used as either an exact or smoothing interpolator. Each grid cell value in an output surface is calculated using a weighted average of all data





































Gridded Surfaces

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The IDW method is optimal when the data has a fairly uniform distribution of input points across the area to be gridded and some degree of smoothing is beneficial; for example, soil samples taken over a regular grid. With this type of data a repeat measurement at a point does not necessarily give the same results as the first measurement. If the input data points are not evenly distributed then using an oriented search ellipse may produce a more representative grid. Selection of the Inverse Distance Weighting method opens both the Search and Inverse Distance tabs. The weighting value assigned to each point within the search ellipse is determined by the distance from the data point to the grid node being interpolated. The further away a data point lies from the grid node the less the point value will contribute to the final value assigned to that node. The distance weighting parameters can be adjusted under the Weighting Model controls in the Inverse Distance tab. A search ellipse ellipse of fixed size and and orientation orientation can be defined; a grid grid cell value is then calculated from the weighted average of all data points that lie within t he ellipse centred on that cell.

Weighting Model The weighting of an input data point is (by default) inversely proportional to its distance from the grid node (a Power Weight Model). Four Power Weight models are available: •

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Linear – the weight of each input point is proportional to its Euclidian distance from the grid node being interpolated. Exponential – the weight of each input point is proportional to its distance from the grid node being interpolated raised to the specified power. Power – the default option – the weight of each input point is proportional to the inverse of its distance to the specified power from the grid node. Gaussian – the weight assigned to each input value is determined according to a 2D Gaussian function centred on the grid node.

Weighting Options The Elliptical weighting option is only available when the Elliptical Search option is enabled in the Search tab. It adjusts the distance weighting function for data points within the search ellipse depending depending on their relative position with respect to the elliptical shell. The Density corrections control dynamically adjusts the search algorithm to optimize grid cell interpolation in areas of data clustering. This can help to enhance detail in datasets where sample points are unevenly spaced (regional geochem sampling) and may produce a smoother more representative grid. The Exact hit distance is a tolerance distance for assigning actual input data values to coincident grid nodes. A certain number of grids nodes will coincide with the input data points. Where grid nodes and data points coincide the distance between them is zero so the data value is assigned a weighting of 1.0 and all other data points in the search radius are given a weight value of zero.





































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Search Tab By default Discover uses a circular search with a radius specified via the Search Distance option. If the node cannot be estimated from the points located within the search radius then the search radius can be incrementally increased and the searching repeated using Search Expansions . If the spatial distribution of the data points is not uniform (i.e. regional data captured at 2km intervals and localized data at 100m intervals) then the use of search expansions may not be enough to populate the grid successfully. The solution to this is to use additional refinement Grid Passes which grid the data multiple times at increasingly higher resolution. By default the search radius is isotropic creating a circular search area. Directional bias can be applied by enabling an Elliptical or anisotropic search.

Sample Selection Input points ‘close’ to the grid node may not be uniformly distributed – eg they may all be on one side of it. This will introduce directional bias into the estimation. This can be resolved by using search sectors of 1, 2 or 4. By adjusting the Number of search sectors and Minimum points required (in each sector) the appearance and smoothness of the output grid can be varied. If any of the sectors contain fewer than the minimum number of specified points the interpolated grid cell value for that node is assigned a null value. Specifying the Use nearest neighbours option enables you to use only the closest Maximum number of samples found within each search sector in each estimation. Contributions Contributions from other points within the search radius are ignored. Enabling the Customise gridding rule option allows a node to be gridded only if a specified minimum number of sample points are located in at least a specified minimum number of sectors.

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You can now experiment with Inverse Distance Gridding Method parameters to create an appropriate looking grid. Go back to the grid in the map window and measure the distance between the sample lines and the sample points along the lines. The grid line spacing is approximately 120m with some infill lines at 60m. The distance along the sample line is around 30m. Start with the default cell size of 15m and a search radius of 70m. Set the Maximum number of samples to 8





































Gridded Surfaces

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Alter the Search Expansions to 1 and observe the infill of the lines further south in the grid.

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In the Output Tab click the Smooth Grid box and change the Smoothing Factor to 5. Save the grid as an ERMapper grid to the same folder as the input points.

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Repeat the process for the Pb and Zn assay columns.

17.

When you are finished open the ELC and check/uncheck the Visibility box next to each grid layer to display the different grids. It is important important that the user has a good understanding of the geology and sample statistics when creating a geochemical grid otherwise the results may be interpreted incorrectly.

Kriging Kriging is a geostatistical gridding method which has proven popular across a variety of industries due to its flexibility and data driven approach to surface interpolation. Kriging is an advanced technique which is based on the assumption that the spatial variability in the measured property of a data set is neither due to totally random nor deterministic constraints. The main advantage of Kriging over simpler interpolation techniques such as IDW is that it uses a weighting model which is adaptive to the inherent trends in a data set rather than imposing a set of fixed conditions upon them. The process of using Kriging in interpolation interpolati on can be complex and requires an intimate knowledge of the structure and variability in the data set so that an appropriate sample model and set of gridding properties can be chosen.

Grid Calculator Use the Grid Calculator to perform any of the following operations: •

•

•

•

Subtract one grid from another – for example, base of weathering from topographic surface. The resulting grid shows the difference, which may be positive or negative values. Add one grid to another – for example, adding gridded Pb and Zn together to produce a combined base metal grid. Multiply or divide two grids together – for example, coal seam thickness multiplied by calorific value to return a grid showing economic product (in derived units). Stitch adjoining grids together to make one large grid. This is an addition operation, but where there is no overlap between the two grids. The output grid covers the combined area of both input grids, with null cell values filling the minimum bounding rectangle.

The Discover Grid Calculator can apply arithmetic operations, logic, comparative and Boolean operations directly to grids or between grids in any supported grid format.

Exercise 8.12

Merge the Cu, Pb and Zn geochemistry grids to create a new combined metal grid





































62


1.

Make sure the three grids created in exercise 8.11 are open in a map window.

2.

Select Surfaces>Grid Calculator .

Available grids grids are displayed displayed in the scrollable scrollable list at the top top of the dialog. dialog. This list is initially populated by all grids currently open. Further grids can be added to the list using the Load Grid button, and removed from the list using the Delete Grid button. Use the Information button to obtain details of a selected grid. Grids can be assigned an alias name to enable the shortening of complex file names for ease of use in the expression line. For example, instead of COMBINED_TMI_140403 COMBINED_TMI _140403 = X + Y we can use W = X + Y. To create a grid name alias, double click on the relevant cell in the Alias Name column and type the desired alias name. 3.

Assign each grid an alias name Cu, Pb and Zn by clicking in the Alias Name cell next to each grid.

The Grid Calculator requires a formula to be specified in the Expression line in the middle of the dialog. Complex grid operations such a Boolean and decision functions can also be applied. These grid operations are described in detail in Appendix H - Grid Calculator Syntax in the Discover Reference manual.

4.

In the Expression box enter a name for new grid to be created such as COMBINED_METAL followed by the “=” sign.

5.

Highlight the Cu grid from the Grids list and use the Add Grid button to move the grid down to the expression line. Add the “+” operator and repeat the process for the Pb and Zn grids.

6.

Use the Save As button to save the new grid to the Encom







































Gridded Surfaces

Note

63

Both grids used in the grid arithmetic operation must be registered in the same coordinate coordinate system. However, the two grids can have different cell sizes. The output grid has the cell size of the first input grid.

Gridding Geophysical Data Geophysical data can also be gridded in the same way as elevation data. Gridding of geophysical data can enable magnetic or gravity anomalies (high or low) to be distinguished from background values or enhance structural lineaments over a project area.

Exercise 8.13

Grid magnetic data and apply a grid filter

1.

Open the EL2290_CH_AMG table from the Encom Training\Copper Hill\Tenements folder and the COPPER HILL GROUND MAG table from the Encom Training\Copper Hill\Geophysics folder into a map window.

2.

Select Surfaces>Create Grid and highlight the COPPER HILL GROUND MAG table. Select the Corrmag field to grid and choose Minimum Curvature from the Method tab.

3.

Use the Statistics Explorer and Data Conditioning to remove any spurious data values from the dataset before we grid it.

The Minimum Curvature gridding method is widely used in many branches of science and research. This method creates an interpolated surface similar to a thin, linearly elastic plate passing through each of the data values defined in the input dataset. An important criterion in creating a surface is that it has a minimum amount of bending forced upon it to conform to the data points. The degree of bending is constrained by a ‘tension’ parameter and this can be specified both within the data area but also near the edges. Minimum curvature gridding generates the smoothest possible surface while attempting to honour the data as closely as possible. Like all gridding methods, minimum curvature gridding is not an exact interpolation and therefore some error at a majority of data points is observed. Minimum curvature attempts to fit a surface through all of the data points without putting any abrupt kinks in the surface. Between the fixed observation points, the surface bends according to the Interior tension. This parameter is used to control the amount of distortion on the interior with the higher the tension, the less the distortion. The Boundary tension controls the amount of distortion at the edges. By default, the boundary tension is set to 0.





































64


4.

Use the Minimum Curvature defaults and a Cell Size of 5.

5.

In the Output tab select the Concave Hull from the Clip option pull-down list and no smoothing. It may take a moment to redraw the preview window.

6.

Save the grid in ERMapper (.ers) format into the Encom Training\Copper Hill\Geophysics folder.

Filtering a Surface Grid filtering is a common method of applying digital image processing techniques to gridded data. Filters can be used to improve the general appearance of gridded images by smoothing or suppressing high frequency noise. Filters can also be used to enhance detail in an image by displaying the contrast between features (i.e. identifying edges). The Grid Filter is a power tool that provides the following functionality: functionality: •

•

•

Apply Convolution grid filters including smoothing, edge enhancement, sunangle and user-defined filters Apply Geophysical FFT filters including Reduction to Pole, Vertical Derivatives, Band Pass Apply Padding to grid to remove edge effects

The Grid Filter tool has an interactive dialog to allow you to see the effect of any applied filters. More than one filter can be applied with a cumulative result. The Grid Filter dialog contains three display windows. The top Input Grid window





































Gridded Surfaces

9.

65

Click the Save button to save the filtered grid to the Encom Training\Copper Training\Copper Hill\Geophysics Hill\Geophysics folder.

List of Available Grid Utilities The Discover Grid Utilities menu provides the f ollowing functionality: •

Classify – Classify each grid cell into one of a number of ranges

•

grid to the non-null non-null area of another grid grid Grid to Grid Clip – Clip a grid

•

•

Clip - Define a region using an irregular polygon or rectangle and remove the portion of the grid that lies within or outside this region. Convert - Input a data grid in one format and save to another grid format.





































66


•

•

•

•

•

•

•

Flip - Invert the rows or the columns of a grid in their location either horizontally horizontally or vertically. Merge – Merge several several grids grids to form a new grid Overlay - Modify grid cell values based on polygon boundaries in a specified TAB or MIF vector file. Replace - Allow specific grid values (such as Nulls or nominated values) to be replaced by another data value or Null. Reproject a grid into a new coordinate coordinate system Reproject – Reproject

Resample - Grids can be re-sampled to a new cell size using any of three available interpolation schemes. Rotate - A grid can be rotated about its defined origin by a specified angle. Interpolation processing is required for this procedure.

•

Shift - Apply an easting or northing offset to the origin location of a grid.

•

Slope - Assigns cell values of either maximum slope angle or direction

•

•

•

•

Split - Used for multi-banded grids, this operation outputs separate component grids of the individual single bands. Vectorize - Converts each grid cell into a polygon in the output TAB file and assigns each polygon a grey-scale value. Viewshed - Compute the view-shed of a tower of a specified height above the grid to an observer at a specified height above the grid. Volume – Calculate the volume between two grids

Displaying Surfaces in 3D The Add Surface button within the 3D Window adds a Surface branch to the Workspace Tree, from which the Surface Properties dialog can be accessed. This powerful control provides a number of surface visualisation options, including: Add Pseudocolour Pseudocolour Surface Surface Add Contour Contour Surface





































Gridded Surfaces

Data Location: and

67

Training 3D\Training 3D\Traini ng 3D\Geophysics\IP_Resistivi 3D\Geophysics\I P_Resistivity ty Training 3D\Training 3D\Structure 3D\Structure

1.

In the Discover 3D window, reopen the Interp_Structures.dxf Interp_Structures.dxf vector file from the Structure directory.

2.

Select the Add Surface button in the toolbar. This will add a ‘Surface 1 []’ branch to the Workspace Tree . Double click on this to open the Surface Properties dialog. Under the 3D Surface tab, click on t he Open File button, and browse to the Geophysics\IP_Resistivity Geophysics\IP_Resistivity directory. Open the IP_Collins file.

3.

Ensure the Auto Apply option at the bottom the Surface Properties dialog is ticked off.

4.

In the Surface Properties dialog, double click on the Surface sub-branch in the Grid Group window. Adjust the Offset slider to -500 and the Scale slider to 2. Click OK to display the gridded surface. This tab also contains options to apply Compression to the grid surface, increasing display efficiency and redraw speed in the 3D environment when display large grid surfaces.

5.

The 3D Surface tab allows the Transparency of the surface to be altered. It also provides controls to display the surface as with either Fill or Lines or both.

6.

The Colour tab provides 3 options for controlling the colouring of the grid surface. An RGB (Red Green Blue) or HSL (Hue Saturation and Lightness) Interpolation can be applied via the Advanced Colour Options button. End member colours for can be set for these, as well as the number of colours displayed. Alternatively, an existing LUT (Look-Up Table) can be selected from the pull-down list. For all of these options a range of Colour Mapping options are available at the bottom of the dialog: Linear, Band Pass and Histogram. Note that Band Pass and Histogram Colour Mapping can be applied simultaneously.

Exercise 8.15

Create a colour scale for the DEM.

1.

Select the Floating Colour Bar button on the Data Objects toolbar. Within the 3D view, draw a rectangle of the desired colour scale size. This can be modified after creation, by first select the shape, then either moving by







































68


white. Under the Arrangement tab, set the Padding to 70, and press OK. Resize the Colour Scale window to remove the excess space on t he right.

Exercise 8.16

4.

Double click on the Floating Colour Bar branch. In the Appearance tab , disable the Cell Colour Transparent option, and ensure that this is set to white. Under the Arrangement tab, set the Padding to 70, and press OK. Resize the Colour Scale window to remove the excess space on t he right.

5.

The Colour Scale can also be applied to other colour modulated datasets such as drillholes, voxel models, 3D points and feature databases.

Displaying multiple surface grids in 3D.

Data Location:

Training 3D\Training 3D\Trainin g 3D\Topography

1.

Additional grid surfaces can be added to the 3D environment in a number of ways. They can be added to the existing Surface branch (Grid Group) from within its Surface Properties dialog or via the menu command or shortcut button (add Surface). Alternatively, a new Surface branch can be added via right-clicking on the 3D Map branch, selecting Add Data>Surface, which will allow independent independent control of each surface’s visibility from the Workspace Tree rather than from within the Surface properties dialog.

2.

Use one of these methods to add the DEM_5m topographic grid to the display. Alter its visibility, and experiment with the options discussed in exercise 1 (Colour table, Compression, Colour mapping, Scaling, etc).

3.

If Scaling is to be applied globally across the 3D dataset, remember to do so by double-clicking on the 3D Map branch, selecting the Scale tab, and adjusting accordingly. The Lighting tab of the 3D Map Properties dialog can be used to adjust the sun angle/azimuth.

4.

Close all the Surface branches when complete.





































Gridded Surfaces

69

(eg geochemical or geophysical grids) should be exaggerated independently.

Exercise 8.18

Display a geophysical grid as contours over a topographic surface..

Data Location:

Training 3D\ Geophysics\Magnetics

1.

Within 2D open and create contours for the Mag grid; try using contour intervals of 50 and 100nT.

2.

Display these contours as vector objects in 3D, using the DEM_5m grid to define the Z value.

3.

In 3D, exaggerate exaggerate the Z scale by a factor of 5.









































































2D Drillholes

9

2D Drillholes

Drillhole menu and toolbar items

71





































72


•

Colour downhole data using colour pattern look-up tables

•

Display profiles of multiple surfaces in section view

•

Create section layout including map grid and titleblock

•

Log style display for individual drillholes, with up to 24 data columns

•

Digitize section interpretations eg lithological type or ore-body boundaries

•

Downhole data compositing by attribute, cut-off grade, elevation or depth

•

3D coordinates are calculated on-the-fly

•

Sectional resource calculator

•

Extract maximum and EOH downhole values

•

Display drillhole info tool

•

Export sectional interpretations interpretations to 3D DXF files

•

Export a section bitmap to Encom Profile Analyst

Steps to Create Drillhole Sections A drillhole dataset dataset is made made up of a series series of tables containing containing information information such as drillhole collar location and geometry, downhole survey measurements, downhole geochemical, geological or geophysical data and other related information. To create drillhole sections and plans use the following steps: 1.

Organize all drillhole data into a format recognized by MapInfo. File formats







































2D Drillholes

73

Drillhole Data Format The Drillholes module in Discover can use drillhole data captured in a number of different formats. Discover can use drillhole data stored in any database format that MapInfo can read, including Access and ODBC databases. Discover does not need to make any alterations or additions to the source data. Discover calculates 3D coordinates for downhole samples when it displays the drillhole, which mean means s that it is not necessary to store these coordinates coordinates in the original data tables. This improves improves ease of use with Microsoft Access database tables and read-only tables (such as Excel spreadsheets). Also, changes to the collar coordinates or to the downhole surveys do not require downhole coordinates to be recalculated. Drillhole data is stored in a number of related tables, with the Hole ID acting as the key to link the different tables. Some or all of the following data tables are used to define the project.

Collar Table The collar location table is a mappable table containing point objects for each drillhole collar. The collar table must include the following columns: HoleID





































74


•

Dip

Depth, Azimuth and Dip columns must be numeric and dip values may be positive or negative. It is unlikely that other data is included in this table and Discover does not check for any other columns. Drillholes having no downhole surveys are displayed as straight lines using the Dip, Azimuth and Total Depth values from the Collar table.

Note

The actual names and order of the mandatory columns is not important, as to the columns are nominated during project setup.

Downhole Data Tables Downhole data tables are non-mappable tables that contain geochemical, geological or geophysical data values for selected intervals down each drill hole. A drillhole project can contain multiple downhole data tables. The downhole data tables must contain the following columns: •

HoleID

•

Depth From





































2D Drillholes

75

Grid and Contour Surfaces Discover can extract profile information from gridded and contoured surfaces (such as surface topography and soil geochemistry) for displaying in the drillhole section. Grids can be in MapInfo, ER Mapper or Geosoft format. Contoured surfaces must consist of polylines attributed with the appropriate Z value.

Surface Geology To display a geology layer, an appropriate surface file must also be used. A gridded DEM surface provides the best surface profile however attributed contour data can also be used. When using contour data the surface geology (or polygon) layer is only shown in the area covered by the contour data. Discover does not extrapolate data outside the limits of the topography surface.

Create Drillhole Project Defining a drillhole project is the first step in processing and visualising your drillhole data in Discover. The drillhole project brings together all of the associated drillhole data tables (as described previously). Once a project is defined, select the project and all relevant tables will be automatically opened.

Exercise 9.1

Set up a Drillhole Project using Discover





































76


3.

The Project Definition dialogue box is displayed. In the Collar and Survey Tables section of the dialog box, click on the Collar Table pull-down list and select Open a Table. Choose the COLLARS table.





































2D Drillholes

77

7.

The Assign Spatial Columns dialog is displayed and you will need to ensure that the column names match those required for each table. After verifying that the information is correct, click OK. Do not click on the Down Dip is negative checkbox as the sample data does not have a negative sign preceding the dip value. The project setup is now complete.

8.

Training\Drilling folder there is an Access database In the Encom Training\Drilling containing downhole lithology data. Open the DH_LITHOLOGY table into







































78


•

•

•

Exercise 9.2

numbers can be be an Duplicate sample numbers – duplicate sample numbers indication of data entry errors and need to be identified.

Overlapping sample intervals – sample intervals do not usually overlap in a downhole data table and any such intervals must be identified. Sample interval gaps – although many drillholes do not have contiguous sample intervals from top to bottom, it is useful to list where gaps are located as part of the data validation process.

Validate drillhole project tables





































2D Drillholes

Create Drillhole Sections and Plans After defining a drillhole project project and validating the drillhole database, database, you can display the drillhole data in section or plan view. Three methods are available for specifying sections: •

Type in the required information

•

Manually select the required collars

•

Draw a line that will represent the section.

79





































80






































2D Drillholes

81





































82


the SURFACE_GEOLOGY layer draped over it to show the geological intersections at surface.

Use Data Display Setting allows you to apply downhole data display such as linegraphs, histograms histograms and text labels to the drillholes at the time the section is generated. Before you can use this function you will need to define a template for the downhole data using the Display Downhole Data form. Show Depth Ticks and labels down the hole. Discover can place a tick and a text label at nominated depths, for example every 50 metres, down the hole. This can be used as an aid to interpreting and correlating with other information. 7.

Click OK to exit this dialog and Plot Now in the main dialog. An envelope is







































2D Drillholes

•

83

Structure Ticks – Lines drawn across the drillhole trace showing the true or apparent dip of measured structures





































84


Create Drillhole Colour Pattern Drillhole colour patterns can be used for colouring either numeric data (ranged





































85

2D Drillholes

From

To

Colour

0

1000

Blue





































86






































2D Drillholes

87













































































































































































































































































































































































































































































































































































































































































































































































































































































































































118


6.

Set the cell Size to low resolution.

7.

Experiment with a number of different parameter combinations, and observe the resulting grids. A search distance of 20 with 3 Search Expansions is a good starting point. Obviously a larger search radius, larger number of search expansions, expansions, and less strict selection parameters parameters will result in a greater coverage coverage of calculated output cells. However this is likely to be at the expense of not preserving the original data points, and exaggerated/unreasonable data extrapolation. It is recommended to note the parameters used for each grid, for comparing the various grids effectiveness and validity.

8.

Colour the lithological model using the colour legend (DHgeology_Lithology) created in Exercise 10.5. Use the Colour tab of the VoxelModel Properties Properties dialog to select and apply this legend.

9.

This legend can also be used to control the display of individual lithologies/rock lithologies/rock types in the Isosurface and Threshold tabs . In the Lithology tab, use the browse button to select the DHgeology_Lithology legend, and press Apply. Then go to the Isosurface tab and set the top pull-down to Lithology, You can now control which individual lithologies lithologies to display, with individual transparency transparency settings for each.

10.

Alternatively, turn of the Isosurface display via the option under the Appearance tab . Then open the Threshold tab and enable the Threshold by option: multiple rock types can rapidly be displayed using this interface. Again try applying applying the Cloud view.





































3D Digitization and Solid Generation

12

119

3D Digitization and Solid Generation Attributed geological geological interpretations interpretations (such (such as mineralization mineralization or or alteration zones, lithological boundaries, boundaries, etc) can be digitized into 2D drillhole cross sections, as illustrated in exercises 9.9 & 10.7. These boundaries can then be displayed in 3D. However these interpreted boundaries are limited spatially to the vertical planes of the 2D cross sections. Alternatively Discover Discover 3D 2.5 now gives the user user the powerful powerful ability to digitize digitize and attribute points, polylines and polygons directly into the 3D environment as Feature objects. This functionality utilises the 3D Cursor Plane as a drawing plane; digitization is therefore free of the orientation constraints constraints imposed in the 2D environment. Digitization directly into the 3D environment also allows the user to visualise multiple datasets whilst digitising their interpretations, such as drillholes, voxel models, gridded surfaces, point datasets and vector models. 3D solid dxfs can then be wireframed from Feature Objects (whether these comprise 2D and/or 3D digitization) by using the 3D Solid Generator. This allows interpreted lithological or mineralisation outlines to be converted into coherent 3D models.

Exercise 12.1

Import 2D section boundaries into 3D as a Feature Database. Create solid dxf’s based on an attribute field.

Data Location: Location:

Note

Encom Training\Training Training\Training 3D\Drilling\Project 3D\Drilling\Project Files

1.

In the 2D interface, ensure that the Copper Hill drillhole project is open, and that sections 5300-5600 are open, including their respective ‘B’ layers

2.

Send these digitized section B layers to Discover 3D using the Discover 3D > View Section Boundaries menu option.

These may have been created previously as ‘FeatureExport.fdb’ (exercise 10.7). If so, then this could be opened directly from within Discover 3D using the Features>Open menu option. Alternatively these sections boundaries were also exported as dxf files: these could be imported via the Features>Import menu option, importing these vector objects into a new feature database.

3.

Change to the 3D interface.

4.

Examine the feature datasets attributes in the Features Spreadsheet (open the Information Sheet, and select the Features tab ; ensure that the FeatureExport.fdb FeatureExport.fdb is selected from the pull down list within this view).

5.

Open the 3D Solid Generator (Utilities>3D Solid Generator ). Assign the correct Feature Database in the top pull-down list; the Output file will automatically automatically be named after this with a .DXF suffix and placed in the source file directory (this can be altered).

6.

Assign the Feature_Code field as the Body ID Field. This will force the tool to generate a separate solid for each series of attributed objects





































120


7.

A number of End capping styles are available; in the majority of instances a Flat style is recommended (using None will prevent a volume calculation from being returned).

8.

Under the Algorithm Options button, untick the Structure Analysis option.

9.

Press Apply to run the tool. The preview screen will display a series of green lines indicating the join order of each series of feature objects, as well as the final wireframed solids. In the main 3D window, a new Vector branch will be added to the Workspace Tree, with a sub layer representing each attributed solid. The display of each sub layer can be independently controlled via the Surface tab of the Voxel Properties Properties dialog (fill and line colours, wireframe display).

Digitization Exercise 12.2

Digitize and attribute features into a new database and edit.

Data Location:

Note

Training 3D\Drilling\ Project Files

1.

Ensure that the Copper Hill drillhole project is open in 3D, with the holes modulated by both geology and assay fields.

2.

Create a new Feature Database by selecting the Features>Create menu option. In the first dialog of the following wizard, assign the database a name ‘Digitization’ and place it on the \Encom Training\Training 3D\Drilling directory.

3.

The second wizard dialog allows the names and types of the various feature database database fields to be set. By default this includes a Description field that can hold character attributes; however generally it is recommended to create a user specific specific attribute field. Use the button to add a new ‘Geology’ ‘Geology’ field, with a text width of 30 characters. Press Finish to complete the database.

4.

Feature Objects can only be digitized digitiz ed into an editable database, and only one database can be editable at a time (as in MapInfo). In the Workspace Tree, make the ‘Digitization’ feature database Editable ; the Cursor Plane will be displayed. The Cursor Plane provides the drawing reference plane for feature objects; turning off the Cursor Plane will make the editable layer uneditable.

5.

Manoeuvre the Cursor Plane (controls discussed in Chapter 4 i.e. the keyboard arrow and Page Up/Down keys) into a desired location.

The Cursor plane can also be snapped to the plane of an existing feature object. Ensure the FeatureExport.fbf is open and make it Selectable in the Workspace Tree. Enable the Select tool, and double click on one of the existing polygons in this database. The Cursor plane will align to the orientation of this polygon.

The Cursor plane can also be snapped to the plane of an image by enabling the Bond to Image Select tool





































3D Digitization and Solid Generation

121

6.

Experiment with the Object creation buttons on the Feature toolbar. Note that holding down the mouse button whilst drawing a polyline or polygon will create a continuous series of nodes. Double-click the mouse to finish either of these object types.

7.

Objects can be attributed directly after digitization by enabling the Confirm Feature button. A browser dialog will appear; click twice (slowly) to edit the Geology field.

8.

The amount of 3D data displayed either side of the Cursor Plane can be controlled via a Clipping Plane, duplicating the functionality of section envelopes in 2D. This allows digitization based on, for example, only drillhole traces within 50m of the cursor plane, rather than all data behind the cursor plane. Open the Cursor Plane Properties dialog (via the button on the Cursor Plane toolbar). Set the Clip option to Envelope , with a clip distance of 50m (i.e. 50m of data either side of the Cursor Plane will be displayed). displayed). Also set the Step interval to 10m; each press of the keyboard Page Up/Down buttons will shift the cursor plane laterally 10m.

9.

Setting the Clip option to Slice will display only the specified distance of data behind the cursor plane. The Clipping plane can be toggled On/Off using the Clipping Plane button.

Experiment digitizing a series of attributed polylines/polygons into adjacent planes. Generate solids from these.

Feature editing Object editing requires one or more objects to be selected in an Editable feature database databa se (ensure the Editable icon is enabled in the Workspace Tree). Enable the Edit mode button on the Feature Toolbar ; all nodes/vertices on the selected objects will be displayed. Double clicking on a editable object will also enable the Edit mode for the object: The following Editing functionality is available with the Select button enabled: •

•

•

Moving an object within the cursor plane – hold down the keyboard SHIFT key whilst dragging the object to its new location. The object will be moved within the cursor plane. If more than one object is selected, all objects will be moved parallel to the plane of the last selected object (i.e. the object to which the cursor plane has snapped)

Offsetting an object with respect to its cursor plane – first hold down the keyboard CTRL and SHIFT keys, then place the cursor over the selected object, ensuring that the cursor does not change to a directional cursor. Left click and drag the object to the new location. The object will be positioned and remain parallel parallel to its initial orientation, i.e. it will be offset. If multiple objects are selected, they will be offset to the plane of the last selected object. Deleting an object- with or without the Edit mode enabled, press the keyboard Delete button to remove an object. Alternatively, right click on the object (not a node) and select the Delete option from the pop-up menu.





































122


•

•

•

•

Note

Exercise 12.3

Repositioning a node – placing the cursor over a node will change the cursor to Move cursor. Click and drag the node to it’s new location within the cursor plane. Add a node – placing the cursor over a polyline/polygon segment will change to cursor to an Add Node cursor. Click to add a node at this location; this node can then be repositioned as above. Alternatively, rightclick when the cursor is over the segment and choose Insert Node from the pop-up menu. Delete a node – select a node by clicking on it (the cursor plane cross-hairs will converge on the selected node) and press the keyboard Delete key. Alternatively, right right click on the node and choose the Delete option form the pop-up menu. Elastic movement of nodes – Moving a node whilst the the Activate Elasticity button is enabled will move its neighbouring nodes. The Radius of this options affect is set via the arrow button adjacent to the Elasticity button. This dialog also contains options controlling how the affected nodes are moved: this affect is represented graphically next to each option (Gaussian, Square, etc).

Feature Datasets can be exported using the Feature>Export menu option as a number of formats, including dxf’s and ESRI shape files.

Create a bifurcating solid

Encom Training\Training 3D\Geology 1.

Import the Bifurication_Initial.dxf Bifurication_Initial.dxf into a new feature database using the Feature>Import menu option.

2.

Generate a solid (no Body ID) and note the handling of the separation (bifurcation). (bifurcation). Also note the polygon not utilized.

3.

In order to handle bifurcating bifurcati ng solids, intermediary shapes are required to guide the algorithm. Import the Bifurication_Final.dxf as a new feature database, and note the extra polygons guiding the separation of the body.

4.

Generate a solid using the Bifurication_Final.fdb. Bifuricati on_Final.fdb. Ensure that the Structure Analysis Algorithm Option is enabled to handle non-overlapping polygons.







































Example Exercises

13 Exercise 13.1

123

Example exercises Convert a series of drillhole fault intercepts into a 3D fault plane DXF.

Encom Training\Training 3D\Drilling\Project Files 1.

Open the Copper Hill drillhole project into both 2D & 3D. A number of drillholes contain contain a ‘Fault2’ intercept; In 3D, colour the drillholes so that only the Fault2 lithology is displayed: -

In the Drillholes Fields tab, having set the lithology field and appropriate colour legend (created previously for this field), open the Field Data Conditioning dialog.

-

Use the Browse button to open the ‘Only_Fault2.edc’ file located in the Project Files directory. This is a list of all lithological units in the Copper Hill project except the ‘Fault2” attribute; all units listed here will be converted to Null intercepts. Apply this null list.

We would like to create a fault plane encompassing these intercepts, but without manual digitization. digitization. Instead we will grid this data in 2D to create a grid surface 2.

In 2D, desurvey the geology table (creating X, Y and X From and To coordinates). coordinates). Select out the Fault2 attributed intercepts, and save this as a new table called Fault2_points. Open this table.

3.

We want to model our fault plane on the mid-point of these intercepts. Create 3 new columns (eg X_mid, Y_mid and Z_mid) and populate these with the average of the appropriate From and To fields using Table>Update Column, as below:





































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DEM grid with the Grid Calculator, using the syntax pictured below. View this surface in 3D.

7.

If desired, the depth and lateral extents of the Fault_new grid could be clipped with a polygon using the Surfaces>Grid Surfaces>Grid Utilities>Clip tool.

8.

In order to build a fault dxf in 3D using the Solid Generator, we need a series of polylines representing representing this surface. The easiest way to do this is to contour the grid. 25m spacings are recommended for this surface. Call the output Fault2_contours. Ensure that Contour Smoothing is enabled.

9.

Import these contours into 3D as Feature objects. Within 3D, use the Features>Import to browse for the Fault2_Contours.TAB file, saving it either to the cosmetic layer or a new feature database. Ensure to Initialize





































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Movie Making 3D Fly-Through Animation Creation of a 3D Fly-Through Animation is controlled by a wizard that generates a script. Within the script are a series of 3D location points that view the display with different angles and elevations. Smoothly moving from one position to the next creates the animation. The 3D Fly-Through Animation track can be specified from: 1.

MapInfo Professional Professional .TAB file

2.

Flight path specified from data open in Discover 3D

3.

Manually specifying specify ing various predefined views

4.

Edit an existing Fly-Through Fly-Through (FLY) file

Other features of the 3D Fly-Through Animation feature include: •

Ability to repeat operation or reverse to replay backwards

•

Smooth view along predefined track using a Bezier curve approximation

•

•

•

•

Control frame rate, flight speed, view pause, view rotate and point examination Create 3D DXF file of a created flight track including definable points to mark view points Capture fly-through as an AVI movie for later viewing. Selection of video compression (CODEC) provided. Audio identification at set points. These sound effects are heard while a script is being replayed through the computer sound system. Sound cues such as “Note the surface anomalism coincident with this drilling…” can be a useful adjunct to seeing the 3D display replayed. Note that when recorded to an AVI movie file, the sound is not transferred.

How Fly-Through Animation Works A fly-through fly-through animation operates operates by positioning an Eye Point, (also called a





































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Flight path of ‘joined’ Capture Points as they direct their view to Look At points

Each Eye Point can be recorded from a manually positioned location in the 3D map display or at interpolated locations from a predefined flight path defined from a database or MapInfo TAB file. The Eye Points look directly to their associated Look At point and then gradually gradually move and and update with the next Eye and and Look At points points during the animation. The movement from one Eye point to the next can be smoothed or direct (determined by the Smoothing and Tension settings). The speed at which the fly-through travels is dependent on the Playback Speed and Flight Speed (see General Playback Options). Each Eye Point (Capture Point) can have a number of events and properties associated with it. An event may be a pause, sound, change of display property (egg transparency, application of a different LUT, etc) or a rotation of the view about an Eye Point or Look At point. The individual Eye Points and their associated Look At point, including any associated events, are saved to a script file called a FLY file. These files created for a given project area provide the mechanism to replay the fly-through animation as desired.





































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Create 3D Fly-Through File Exercise 14.1

Create 3D Fly-through Animation

1.

Open a selection of 3D data into the 3D window including surfaces, images, drillholes, etc. The Fly-Through Fly-Through Wizard can be accessed from the Utilities toolbar button or from the Utilities menu.

2.

In the Fly-Through Creation Wizard: Step 1 – Input Type dialog choose to create the fly-through Manually from the current Discover 3D view . This requires specifying a number of 3D map window views to use as Eye and Look At points which are linked together to form the flight path

Fly-Through Wizard dialog and options to create a flight path script

This Fly-Through Wizard option is the simplest to use as the flight-path is compiled from a list of Capture Points (Eye and Look At points) which are specified by rotating and zooming to different views in the current Discover 3D map window. The capture points are then displayed in the capture order to simulate the flightpath. There are no additional setup parameters for this option.







































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General Playback Options

General playback and flight path options dialog

These options relate to Playback controls and Flight Path Creation. The following Playback controls are available: •

The Loop Style options control the way a script is re-played. re-played. Use the pulldown list to select the desired option. A script can be set to:

Repeat - the fly-through script is played and then repeated from the start continuously. Repeat Reverse - replay the script continuously but in reverse. Repeat Reverse Look - replay the script continuously and in reverse but





































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that the time being calculated for movements is too large then increasing the flight speed shortens the movement times. All replay times get recalculated with new values when this property is altered. The speed of the replay is set in Playback Speed. •

Create Eye and Look Path DXF Files – The flight path and capture points of a script can be saved to 3D DXF files. Two DXF files get created, one for the Eye points and one for the Look At points. The DXF filenames are dependent on the name given to the fly-through file. The DXF files are created in the same directory as the fly-through file. For example, if the output fly-though file path is: C:\DATA\FLY1.FLY, then the DXF files created would be called: C:\DATA\FLY1_EYE.DXF and C:\DATA\FLY1_LOOK.DXF

•

3.

parameter defines defines the size of a symbol to Point Symbol Size – This parameter represent the Eye and Look at points in the created DXF files. For the purposes of this exercise leave the default general playback options.

Add capture points and event details 4.

To create a new capture point, use the 3D Navigation Tools in the Discover 3D map window to rotate and zoom to the flight-path starting point. Click on the Camera button to capture the view. Rotate and zoom the view in the 3D map window until the next flight-through view is displayed and click on the Camera button to capture the point view. Continue to create and capture views to be used in the simulated flight-through path. To insert a new capture point view between two existing views check the Insert Mode box and click the Camera button to insert the current 3D view





































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This button causes the replay script to Pause for a specified duration of time. By default, the time is 1 second, but using the Duration entry field, you can modify this time. Note that a record of this type in the list uses the last Capture Point and then pauses for the required time with no movement. The Rotate View button causes the replay script to halt at the last used Eye position (determined by the previous capture point record) and then rotate the display by an amount determined by an Azimuth and Inclination (looking from the top down). The time to complete the rotation is specified by the Duration. The Rotate Around button causes the replay to rotate the 3D view around the last Look At position (determined by the previous capture point record).The time taken to complete a rotation (as defined by the Azimuth and Inclination settings) is defined by the Duration.

Event Details The Event Details controls of the Fly-Through Wizard are concerned with the Capture Point records. Depending on the Capture Point record selected, the content of the Event Details may differ.

Delete the selected Capture Point from the flight path Update the Eye and Look Positions for the current event with the current 3D





































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coordinate of (10, 10, 10) then the view will be moved 10 units in the X, 10 units in the Y and 10 units in Z direction from the previous capture position. Units are map distance units eg. metres. If the previous capture position is in Absolute values then the new view will move in world coordinates by 10 m in the X, Y and Z directions. 5.

Add a number of capture points using the Pause , Rotate View and Rotate Around options.

6.

To replay fly-through at any stage click the Play button to activate the flythrough. The replay uses the Capture Points according to the Loop Style setting and the various speed and event controls. To halt the replay, use the Stop button. Use the button shown bottom left to display selected captures points in the fly-through replay. Only the capture points highlighted in the list will be included in the replay. This is useful for editing long flythrough without having to view the entire flight path every time.

The script fly-through (FLY) file can also be run from the pop-up menu which is activated by a right-mouse click in the Discover3D map window. The pop-up menu provides the options of Display Fly-Through or Stop Fly-Through .

Output Formats Two output formats are available in the Fly-through Creation Wizard: Wizard: Step 5 – Output dialog: •

•

Save the Capture Points and settings of the fly-through script by assigning a file name and location in an Output File. The settings are saved as a FLY file and can be restored for later use with the same project dataset. A FLY file can be activated via the Display Fly-through option option on the Discover 3D map window right-mouse click pop-up menu. Save the fly-through as an AVI Output movie file. Movie files allow replay of a fly-through animation completely separated from Discover 3D and are therefore useful for management and overview of a project.





































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7.

Save the fly-through as an FLY file. Once the fly has been created it can then be edited by selecting the Edit Existing Fly-through File option in the Fly-through Creation Wizard Step 1 – Input Type dialog.







































3D Printing and Output Options

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3D Printing and Output Options Print Directly from Discover 3D The File>Print option creates Discover 3D hardcopy output to a printer or plotter. Selection of the Print option automatically outputs a copy of the active window to a printer (where connected) or to a print file (depending on your computer’s print settings). The printing function operates on the active (highlighted) display window only. The output can be scaled or simply made to fit a predefined page size. Output destination is controlled by the File>Page Setup... options but a default printer setting can be defined in the Tools>Options dialog. When invoked, the Print command determines the printer settings, device/paper size and window size for the display. From these parameters, Discover 3D estimates a suitable scale to fit the print. The print output can be previewed using the File>Print Preview option, or by altering the View mode through toggling the Normal View….Page Layout button.

Exercise 15.1

Create a layout page for a 3D view.





































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Export 3D View as Raster Image The File>Save View As option allows the current 3D view to be saved as an image at a user-specified resolution. A range of output image formats are available, including BMP, JPG, PNG, and TIF & EMF.

The Save View As dialog allowing output resolution specification

Add 3D View to MapInfo It is possible to transfer a 3D view displayed in Discover 3D, back to MapInfo Professional. Professional. This is a useful function if you wish to have a 'snapshot' 'snapshot' of a





































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by packaging all relevant files into the same directory in a similar fashion to the Discover>Data Utilities>Save Tables and Workspace utility.

3D Workspace File The Discover 3D Open and Save 3D Workspace menu items allow a 3D work session involving drillholes, images and/or associated tables that are open in Discover 3D and MapInfo to be saved for future use. Instead of having to re-create the MapInfo and Discover 3D views, the various files that comprise a Discover 3D Workspace can be used to open the tables and views in either MapInfo, Discover 3D or both programs simultaneously. To save a current workspace in both MapInfo and Discover 3D, select the Discover 3D>Save 3D Workspace menu option. In the Save 3D Workspace dialog enter an appropriate name for the 3D Workspace file and browse to the preferred preferred folder location. Click OK. When a 3D Workspace is saved a number of files are created in the designated folder: WorkspaceName.D3D WorkspaceName.wor WorkspaceName.egs WorkspaceName.egb









































































Appendix A - Menus and Toolbars

A

Menus and Toolbars File Menu

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View Menu






































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in the Discover menu in MapInfo the following Discover 3D customization utilities are also included: A range of Discover of Discover 3D Options such as: •

Default file locations

•

XYZ indicator display

•

Maximum grid and bitmap file sizes

The ability to Customize the user interface in relation to:






































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Main Toolbar

The Open Session button has the same functionality as File>Open Session. When selected, you are requested to locate a Discover 3D session file (*.EGS). The presented dialog enables navigation to the required file. The Save Session button has the same functionality as File>Save Session. You can save a session and assign it a name if it is a new session.

Undo and Redo buttons. These buttons are used to restore or undo changes made while operating Discover 3D. The number of undo steps is limited to the





































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You can then overlay imagery or contours onto the elevation surface. Add a Voxel Model Model layer to the Workspace Workspace Tree and and assign it to supported supported voxel voxel model files. Add an Image Image (Georeferenced (Georeferenced bitmap layer) layer) to the Workspace Workspace Tree and assign itit to any suitable .EGB file. Georeferenced bitmap files can be created by Encom Discover. Add a vector layer layer to the Workspace Workspace Tree Tree and assign assign it to any suitable suitable vector file. Vector files can be two or three dimensions.







































Workshop Notes

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Workshop Notes

Workshop Notes

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Workshop Notes

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Discover 3D Training Manual

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