The objective of this program is to use GIS to draw important parts of the cross section precisely: the surface profile(s) (from raster), the geologic units and their contact points on the surface, the location of wells/boreholes, and the geologic materials found at the well location, projected as a line into the subsurface. The output is a combination of polyline and point shapefiles. Shapefiles can be converted to 3D for viewing in ArcScene. Visual Basic for Applications (VBA) was used to develop the program. Code is stored in the .mxd. The user defines a sampling interval and vertical exaggeration. Zip file contains an .mxd, user guide, tutorial instructions and tutorial data. Works with ArcGIS 10 SP1. 3D Analyst extension is required.

Latest version 091411: updated documentation, added functionality to output reference grid lines and downhole geophysical log graphs.

Note: At ArcGIS 10, VBA is not part of the standard installation. You need to request a separate free license from ESRI, then install VBA.
Link to download.

Create Geologic Cross Sections--eXacto Section, 9.3

New version requires only an ArcView License! 3D Analyst extension is still required.

The objective of this program is to use GIS to draw important parts of the cross section precisely: the surface profile (using a DEM), the geologic units and their contact points on the surface, the location of wells/boreholes, and the geologic materials found at the well location, projected as a line into the subsurface. The output is a combination of polyline and point shapefiles. One of the advantages of this program is that the output features have a spatial reference, meaning that, when set to the desired map scale, the cross section measurements will always be correct. The geologist can use these as a guide to "connect the dots" when drawing the subsurface contacts. He or she can choose to finish the cross section digitally in ArcMap or export it to a graphics program.

Visual Basic for Applications (VBA) was used to develop the program. Code is stored in the .mxd. The user provides input data: lines of cross section, an elevation raster, geology polygons, well points, and a table with subsurface data. The user defines a sampling interval and vertical exaggeration. The program will convert between feet and meters, depending on the units of the input data. A button control launches a form that obtains the required inputs. The user can choose which outputs he or she wants. The output layers are automatically symbolized and labeled in a new data frame.

The downloadable zip file contains an .mxd, user guide, tutorial instructions, and tutorial data. The user guide and tutorial were created for an older version of the tool and have not been updated.

12/23/2009: Fixed a few more bugs. New version was tested successfully in 9.3 and 9.3.1.
Link to download.

Visualize and Edit 3D Borehole Data in ArcScene

Jennifer Carrell
Illinois State Geological Survey
Champaign, Illinois 61820
(217) 244-2764
carrell@isgs.illinois.edu

Summary from ESRI Support Center ArcScripts Details

The goals of developing this program were to (1) enable geologists to create and view 3D boreholes in ArcScene and (2) enable geologists to edit borehole data directly in ArcScene, based on their interpretations.

Visual Basic for Applications (VBA) was used to develop a custom tool bar in ArcScene 9.3. The toolbar contains 8 button controls, each built to perform a specific task:

1. "Create_3d_lines" takes a table (.dbf or geodatabase) of well log data and creates a 3D polyline shapefile. The shapefile is automatically rendered with a 3D tube symbol.
2. "Edit_attributes" allows the user to enter new values for selected borehole segments.
3. "Edit_zyx" allows the user to edit the location of the borehole by entering new x, y, or z values.
4. "Split_line_at_z" allows the user to split a selected borehole segment at a specified elevation.
5. "Merge" allows the user to merge two or more contiguous segments into one segment.
6. "Update_xyz" updates the coordinate values in the table. This button is intended to be used after borehole locations have been edited outside of ArcScene. Using any of the buttons described above will automatically update the values in the table.
7. "Symbolize_tubes" allows the user to easily change the width of the tube symbol and the field used to symbolize the lines. Using this button will allow tube widths greater than 100, which is the maximum width allowed under the standard symbolization interface.
8. "Plot_gamma" takes a geophysical log (.las format) for a borehole and plots it as a graph along side the 3D borehole line.

The code is imbedded in an ArcScene document (.sxd). The downloadable zip file contains the .sxd, overview poster, tutorial, and tutorial data. The file is 3.8 MB. Link to download.