|3D wireframe of a terrain in *.dm format; topoWf.7z|
|Digitized contour of the fault (2D poly-line) in *.dm format; fault-string2D.7z|
|Orthogonal projection of the digitized fault line on the terrain, in *.dm format; fault-perdtm.7z|
|Projected at 72d angle strings in *.dm format; up-down.7z|
|3D Wireframe of the fault in *.dm format; fault-WF.7z|
A line drawn by a human on paper is "a priori" projection of any 3D string on a plane of a table on which the paper is placed. So is the fault line, indicated by red arrows on the picture below.
From the draftsman's point of view, this is an intersection of a fault plane with the terrain surface, but with pencil and paper he can only draw a flat line.
When we download the digitized string, it will look like a curve somewhere in the air above or below the surface, depending on the elevation we give to it.
What we should do is to project the line on the surface orthogonally (at 90 degrees) to get the 3D projection of the line. To do this, the program offers a command PERDTM, which must be entered into the command line.
Pick up or enter the digitized string name, which you are going to project on the surface in the PERIMIN* cell. Do the same for the surface files: WIREPT* and WIRETR*. Choose a name for output file in PERIMOUT*. Press OK.
Visualizer window shows digitized string (red) and orthogonal projection (yellow) of it on the surface
Face Angle is a function from the Open-Pit Module for controlling bench and overall slope angles, and can successfully be used in our example.
Go to Applications | Open Pit | Set Face Angle.
In this example, the fault is deeping 72 degrees to the NE. Remember the deep angle is the angle between horizontal plane and the fault plane at the measurement point.
Enter the angle and press OK.
We need to project the 3D string on a plane below the surface at the fault deep angle of 72 degrees. From visualization point of view it may be useful to extend the fault plane at some height above the surface.
Tun off all objects, except the 3d string faultsplST in the Sheets tab on the left of Design window. Click on the line (select object by clicking on it) to make it active. It will turn yellow.
Click anywhere on the empty space in Design window to deactivate any previously leftover commands.
Then click on the string to make it activate. It will turn yellow.
Type D for Down. Press OK.
Type 1900 as the Target Elevation of the plane you wish to extend the fault to. Press OK.
Back in Design window, click near the selected line on the left side. A new string will appear on the right.
If you wish to extend the fault above the surface up in the air, select the 3D string again by clicking on it, type pro, and in the appeared dialogue type u in Projection cell, press OK, Type 2800 in Target Elevation cell, press OK.
Before saving, check the strings for crossovers and fix them with string tools if needed.
Now we have an upper and lower projection of a 3D string, which will be used for wireframing
Visualizer view of all stings
Use Wireframes | Linking | Link Strings command (or type ls) to link upper and lower projection strings. The resulting pictures below.