Import UBC DCINV2D/IPINV2D Files

Use the Map > Import > UBC DCINV2D/IPINV2D Files menu option (geogxnet.dll(Geosoft.GX.IP.ImportUBC2D;Run)*), to convert UBC DCIP2D conductivity and chargeability files to Geosoft Grid files and display them to a map.

Use the Add to 3D > Imports > UBC DCINV2D/IPINV2D Files menu option (geogxnet.dll(Geosoft.GX.IP.ImportUBC2D;Run)*), to convert UBC DCIP2D conductivity and chargeability files to Geosoft Grid files and display them to a 3D View.

Import UBC DCINV2D/IPINV2D Files dialog options

Mesh File

Select the model mesh file. This file provides the model specification for the conductivity/chargeability data contained within the model files specified below.

Script Parameter: IP_IMPORTUBC2D.MESH

Topography file

Select the topography file. The "top elevation" value from the topography file gives the true elevation at the top of the mesh; the depths contained in the mesh file are given relative to the top of the mesh.

Script Parameter: IP_IMPORTUBC2D.TOPO

Conductivity file

Select the conductivity model file to convert to a grid. Either the conductivity model file or the chargeability model file must be selected. The conductivity model file must be specified in order to produce a resistivity grid.

Script Parameter: IP_IMPORTUBC2D.CON

Create resistivity grid also

The conductivity model file must be specified in order to create an accompanying resistivity grid. The resistivity is calculated by taking the reciprocal of the conductivity values.

Script Parameter: IP_IMPORTUBC2D.RES: (0:No, 1:Yes, Default 0)

Chargeability file

Select the chargeability model file to convert to a grid.

Script Parameter: IP_IMPORTUBC2D.CHG

Prefix for output filenames

Select a string of text to put at the start of the output grid filenames. Underscores are not automatically included, so if you wish to separate the prefix and the rest of the filename with an underscore, be sure to include it in the prefix text.

Script Parameter: IP_IMPORTUBC2D.PREFIX

[More] - click this button to display additional parameters

Output grid cell size (X)

Output grid cell size (Z)

By default, the output grid cell size is determined by examining the model mesh and selecting the most-repeated value. Normally, in a given row, the padding cells surround, and are larger than, the interior model cells. If a cell size different than the original model cell size is selected, values are interpolated. For the "Z" cell size, the top-most cell size is used as the default value.

Script Parameter: IP_IMPORTUBC2D.CELLX, IP_IMPORTUBC2D.CELLZ

Padding cells to trim on left side

Padding cells to trim on right side

Padding cells to trim at bottom

Select the number of cells to trim from the left side of the mesh model. By default, all cells up to the central "block" of cells are trimmed.

Script Parameter: IP_IMPORTUBC2D.TRIM_LEFT, IP_IMPORTUBC2D.TRIM_RIGHT, IP_IMPORTUBC2D.TRIM_BOTTOM

[Calculate from Mesh File]  

Click this button to calculate the cell size and padding cell values from the currently selected mesh file.

Application Notes

*The GX tool will search in the "...\Geosoft\Desktop Applications \gx" folder. The GX.Net tools, however, are embedded in the geogxnet.dll located in the "...\Geosoft\Desktop Applications \bin" folder. If running this GX interactively, bypassing the menu, first change the folder to point to the "bin" folder, then supply the GX.Net tool in the specified format.

Setting the DUMMY

All values in the input Conductivity file less than 10-8 x maximum conductivity are dummied on input. For example, if the maximum conductivity value in the input conductivity file is 0.1, then all values below 10-9 will be set to dummy. Since conductivities are always positive values, you can represent the dummy value in the input conductivity file with a very small positive value such as 10-32 and skip checking the maximum value in the input conductivity file.

Output Filenames

The output grid filenames are composed of the input grid file names, with the optional prefix, and "CON", "RES" or "CHG" as a suffix. For instance, if the optional prefix is defined to be "L100_", then you will get the following grid filenames:

  • dcinv2d.con -> L100_dcinv2dCON.grd  (Conductivity grid)
  • dcinv2d.con -> L100_dcinv2dRES.grd  (Resistivity grid)
  • ipinv2d.chg -> L100_ipinv2dCHG.grd  (Chargeability grid)

    • Additional XYZ Files

    In addition to the grid files, the import produces Geosoft XYZ files containing the original model data used to construct the grids. The files consist of three columns of space-delimited values. The first two columns give the original UBC (X, Z) model location, while the third value is the model resistivity, conductivity or chargeability. The list of values is the trimmed model, and has all dummy values removed.