4.0 PolyMap METHODOLOGY OF USE

Generally, the usage of PolyMap for creating a MicroMODEL 3-D rock modelling input file proceeds in the order of PolyMap's four main modules. The following section describes the methodology of use for each module. The usage of PolyMap for doing pit designs follows a similar pattern, and is discussed in section 4.2.

4.1 Geologic Data Input Methodology

In order to input geologic data, the user must first define the project information, layers, and maps. When defining the layers, it is important to assign names to all possible areas of the layer. For example, air can be named "AIR", and unknown regions can be called "UNKNOWN."

After the project limits, layers, and maps have been defined, the user can proceed to the second module which facilitates map digitizing and editing. If section maps are being digitized, it is important that a contour map of project topography be digitized or transferred into the PolyMap project. The name of this map should be entered into the project information file so that the topographic profile can be automatically added to each section map when it is initialized prior to the first digitizing session.

In general, it is best to begin by creating paper copies of drillhole cross sections, hand drawing the zones on these maps, and then digitizing from these maps. It is possible to display MicroMODEL section plots as background maps for digitizing directly on screen with a mouse. However, this shortcut should only be used where time constraints are tight, or when zoning is not very complicated.

One big advantage of creating the paper maps is that a light table can be used to insure continuity of the zones from section to section. It is not possible to do this when digitizing directly from the screen.

When digitizing from a table, it may be helpful to use paper copies of the various menus. In particular, a copy of MAINMENU is needed, along with copies of both the POLYMENU and LOCMENU menus for the layer that will be digitized. These menus can be plotted by selecting the appropriate choice in the System Setup Sub-Menu. Table digitizing can be accomplished without the use of menus, especially if the digitizer buttons are redefined.

Each map is digitized in turn, then filtered to remove extraneous points. After filtering, the map is updated in order to create the node-segment file and polygon area file. The program which plots filled polygons to the screen can be used to check each map to be sure that the areas have been defined correctly. Any errors should be corrected before the next map is worked on.

After all maps have been digitized, it is generally a good idea to plot off a series of plan maps or perpendicular sections showing the zone intercepts from the original set of maps. These plots are made with the program that plots updated geology in the Display Maps Sub-Menu. Any wrongly assigned zones will usually stick out like a sore thumb on these plots.

Finally, when all the maps have been checked, the zoning information is translated into the appropriate MicroMODEL input file (usually POLY.RKS). This is done using the appropriate program choice in the Import/Export Sub-Menu.

4.2 Open Pit Design Methodology

In order to use PolyMap for open pit design, the user must first define the project information and maps. In addition, certain programs from the MicroMODEL Digitizing Program Interface Menu can be run to provide any or all of the following:

If floating cones are to be used as guides in the pit design process, then the POLY.CNT style files must be imported into PolyMap plan maps. The best way to do this is from the MicroMODEL PolyMap pulldown menu. Select "Export Cone Contours to PolyMap Map", contour the desired cone, and write it directly to a pre-defined PolyMap map using the "Access PolyMap" button. Alternatively, the user can use the "Export Cone Contours to PolyMap Map" program, but instead of writing directly to PolyMap, write the output to a specified ASCII file. Then, using the PolyMap Import/Export Sub-Menu, import the ASCII file to the desired PolyMap map. Background phases are specified directly within the pit digitizing program with the "Phases" pulldown.

Open pit digitizing is done with the program to digitize topography or open pits. Hand-engineered pits can be digitized with this program, or the program can be used to interactively create pit designs.

After each design has been entered, the pit can be merged with original topography using the MESH program. Prior to meshing, the pit designs and topography should be filtered and checked for figure eights and correct sense of direction. This is all done through the appropriate programs in the Map Editing and Digitizing Sub-Menu. Report quality plots can be generated of these meshed pits using the program to plot Topo maps in the Display Maps Sub-Menu.