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Geocap provides import command objects (CO) for reading stacking velocities organized in ASCII column data.

If the file is large, keep the input as low as possible. To generate a velocity cube only x y time velocity are needed.

Example input: stacking velocities in ASCII columns, size ~ 400MB.

Info
titleReading stacking velocities into a project
  1. Create a Generic folder, give it a proper name
  2. Right click on the folder and select *Import->Stacking Velocities.
  3. Browse in all stacking velocity datasets
  4. The cell structure is kept by specifying 'Value change' and set up 'cell separator' for the actual column
  5. The schema type is set to 'Stacking velocities' to get the correct commands visible on the dataset
  6. In this case the time values are in the z coordinates and the velocity values are scalar values
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Geocap project for stacking velocity data and velocity cubes

The actual project was generated the standard way by opening a new project and gradually populate it with folders when needed. The stacking velocities was imported into a generic folder given the name All points in line cells, just to indicate that the stacking velocities are organized as vertical lines, called line cells in Geocap syntax. The schema setting of the dataset is Stacking Velocities.

The stacking velocity file has nearly 7 million points and there are dedicated COs to make a fast display if necessary like Utilities->Map vertical cells in fast mode. This example applied Map Data and Display survey lines (will only display the top points as lines) to get a visual impression of the different surveys in this dataset.

A closer look at the display shows that it is a collection of many different surveys. The transition between the different surveys may show inconsistencies in velocity data. It is possible and advisable in some cases to adjust surveys to get a better match by standard data manipulation. Gridding stacking velocities into a cube will also smooth out errors and tends to make transitions acceptable.

To display a smaller part of the surveys one can use the CO under Utilities->Display stacking velocities in line mode. Set always the correct attribute (scalar or velocity if field data) and select for example Eliminate outside cursor: A small part of the dataset around the cursor is selected for display and also saved in workspace as elioutcursor. Similar for an area zoomed into when in 2d mode and any dataset saved as workdata in workspace.

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Geocap project for stacking velocity data and velocity cubes

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Cube gridding from stacking velocities

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