g-Space exchanges triangulated surfaces and polygons with GOCAD and SKUA-GOCAD through ASCII files. This is file-level geometry exchange; g-Space does not open a complete GOCAD or SKUA project.

Supported Formats

• GOCAD TSurf (.ts) — import and export of triangulated Multi-Z surfaces; export of triangulated fault surfaces.
• GOCAD PLine (.pl) — import and export of open or closed polygons and polylines.

GOCAD TSurf

TSurf files describe surface geometry with vertices and triangular facets. g-Space reads GOCAD TSurf objects, VRTX or PVRTX vertices, and TRGL triangles. Multiple TSurf objects in one file are imported as separate surfaces. Multiple TFACE sections in one object are combined into one surface.

Import a TSurf surface

1. In Data Manager, expand Multi-Z surfaces.
2. Right-click the destination Time or Depth folder and select Import from GOCAD TSurf.
3. Select one or more .ts files and open them.
4. Review the import report. It lists each imported surface, its vertex and triangle counts, renamed duplicates, skipped records, and failed files.

If AXIS_NAME or AXIS_UNIT identifies a time or depth domain that differs from the selected folder, g-Space asks whether to use the domain declared by the file. When the domain is not declared, the selected folder determines the imported domain.

Export a TSurf surface

Right-click a Multi-Z surface and select Export to GOCAD TSurf. If the object contains picked sticks but no facets, g-Space triangulates the sticks before export. At least three suitable stick points are required.

To export a fault surface, expand a fault in Data Manager, right-click its surface child, and select Export to GOCAD TSurf. Enter the required datum and choose the output file. This command exports the displayed triangulated fault surface, not the original fault-stick representation.

TSurf coordinate and data handling

• Z direction: ZPOSITIVE Depth values are converted to the internal g-Space Z convention during import and converted back during export.
• Coordinate reference system: TSurf coordinates are imported as stored. g-Space does not transform them from the coordinate-system block. Verify that they match the project CRS before import.
• Units: missing axis units produce a warning and are assumed to be metres. Exports declare X, Y, and Z in metres.
• Properties: trailing values on PVRTX records and other surface properties are not retained. Only XYZ geometry and triangle connectivity are exchanged.
• Names: the TSurf header name becomes the surface name. If that name already exists, g-Space adds a numeric suffix.

GOCAD PLine

PLine files describe connected line geometry. g-Space reads GOCAD PLine objects, ILINE sections, VRTX or PVRTX vertices, and SEG connections. Connected loops become closed polygons; open chains remain open polylines. Disconnected segment chains are imported as separate polygon objects.

Import polygons from PLine

1. In Data Manager, right-click the Polygons root.
2. Select Import polygons from GOCAD PLine file.
3. Select one or more .pl files, then specify the source coordinate system and measurement system in the import dialog.
4. Review any import report warnings. Invalid records are skipped when valid geometry can still be imported.

Export polygons to PLine

Right-click an individual polygon and select Export to GOCAD PLine file, or right-click a polygon folder and select Export all polygons to GOCAD PLine file. g-Space writes each polygon as a GOCAD PLine object with one ILINE. Closed polygons include a final segment connecting the last vertex to the first.

PLine limitations

• Only XYZ coordinates, names, segment connectivity, and open or closed state are retained.
• Per-vertex PVRTX properties and property metadata are discarded during import.
• A PLine with vertices but no SEG records is imported as one open polyline in vertex order.
• Malformed vertices or segments generate warnings and are skipped. A file with no valid line geometry is rejected.

See Also

Data Manager · Fault Data Formats · GIS Data Formats · Model Data Formats