The standard GUI assumes the incoming velocity volume is an RMS (stacking) velocity volume.
Use the following procedure to import the data as an average velocities:
- Import the average velocity volume as per usual as if it were RMS velocities; the import procedure creates an ASCII file on disk of inline/xline/time/RMSVelocity
- Delete the velocities from the model (Edit > Delete Stacking Velocities > All Lines) then save the model (this is to ensure that if the Dix fly-out is used by mistake or in a workflow, the real average velocities aren’t overwritten).
- Go to the model folder and locate the “import” subfolder
- Edit stacking_velocity.dat using a text editor, and insert two columns of zeroes before the last column (so you have inline/xline/time/0/0/Velocity). The last column will be read by VelPAK/Velit as Average Velocity (the 5th column is read as depth). You can use ScanIt or a column editor such as “cream” if the file is too big for Excel.
- In Velit/VelPAK, use “File > Import > Profile Stack…” and select the edited file; don’t forget to select the corresponding survey in the “Prefix” dropdown.
The velocities are imported as average; on the velocity display, you can plot the average velocities, convert them to XYZ data etc. as per usual.