UBC to Voxel

Use the Voxel > Conversions > UBC to Voxel menu option (geogxnet.dll(Geosoft.GX.VoxUtils.ImportUBCToVox;Run)*), to import UBC 3D Model & Mesh files to a Geosoft Voxel.

UBC Mesh Tools 3D Model to Voxel dialog options

Output voxel

Specify the name of the Geosoft Voxel file to generate (.geosoft_voxel).

Script Parameter: IMPORTUBCTOVOX.OUTPUT_FILE

Model file

Browse to select the UBC Model file to import.

Script Parameter: IMPORTUBCTOVOX.MODEL_FILE

MSH Header file

Specify the Mesh file (*.msh) containing a description of the 3D mesh. See below for the format.

Script Parameter: IMPORTUBCTOVOX.MSH_HEADER_FILE

Dummy value

Specify a value to be interpreted as dummy in the import.

Script Parameter: IMPORTUBCTOVOX.DUMMY_VALUE (default -9.0)

  • There is no fixed dummy value in UBC mod files; it is normally set as -9.0, but it can be -90.0– for instance if there is real data smaller than -9.0.s.
  • Coordinate System

    Coordinate System

    The Coordinate System dialog allows you to specify the correct coordinate system information (Datum and Projection Method) for the incoming UBC 3D Model/MSH file.

    Script Parameters:

    • IMPORTUBCTOVOX.IPJ_NAME

    • IMPORTUBCTOVOX.IPJ_DATUM

    • IMPORTUBCTOVOX.IPJ_METHOD

    • IMPORTUBCTOVOX.IPJ_UNITS

    • IMPORTUBCTOVOX.IPJ_LOCALDATUM

    Application Notes

    *The GX.NET tools are embedded in the geogxnet.dll file 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" directory, then supply the GX.NET tool in the specified format. See the topic Run GX for more details on running a GX.NET interactively.

    If a 3D Viewer is open during the import, then the output voxel will be displayed in that 3D view. Otherwise, the output voxel will be displayed into a new Voxel Viewer window. If the output voxel does not display, open the Advanced Settings dialog (Project > Settings > Advanced) and under the Voxel Settings section, check if the Display Created Voxels option is set to "True".

    MSH Header File Format

    This file contains the 3D mesh which defines the model region.

    The mesh has the following structure:

    NE NN NV

    E0 N0 V0

    ?E1 ? E2 ... ? ENE

    ? N1 ? N2 ... ? NNN

    ?V1 ? V2 ... ? VNV

    NE  Number of cells in the East direction.

    NN  Number of cells in the North direction.

    NV  Number of cells in the vertical direction.

    E0, N0, V0  Coordinates, in meters, of the southwest top corner, specified in (Easting, Northing, Elevation).

    Model File Format

    Model files consist of a total of NE*NN*NV values - one per line.

    Example:

    -9.0000000e+000

    -9.0000000e+000

    1.0607292e+001

    1.0642567e+001

    1.0762947e+001

    1.0782325e+001

    1.0803412e+001

    1.0837755e+001

    etc...

    File structure of model .sus:

    sus1,1,1

    sus1,1,2

    :

    sus1,1,NV

    sus1,2,1

    :

    susi,j,k

    :

    susNN,NE,NV

    susi,j,k susceptibility at location [i j k].

    [i j k]=[1 1 1] is defined as the cell at the top-south-west corner of total number of lines in this file should equal NN NE NV, where NN is the in the North direction, NE is the number of cells in the East direction, and NV cells in the vertical direction. The lines must be ordered so that k changes the 1 to NV), followed by j (from 1 to NE), then followed by i (from 1 to NN).

    The dummy value is -9.0, and is automatically converted to a Geosoft dummy on import.

    The above descriptions are derived from the following document: MAG3D

    A Program Library for Forward Modelling and

    Inversion of Magnetic Data over 3D Structures

    VERSION 3.0

    Developed under the consortium research project

    JOINT/COOPERATIVE INVERSION OF

    GEOPHYSICAL AND GEOLOGICAL DATA

    UBC–Geophysical Inversion Facility

    Department of Geophysics and Astronomy

    University of British Columbia

    Vancouver, British Columbia