Seismic data is used to visualize the Earth's sub surface. This is achieved by measuring travel times of reflections from pressure waves propagating through the ground. Seismic data and interpretations of seismic data will therefore often have z values in travel time, not depth. In order to get a depth value for the travel time values, we need to do a depth conversion. A depth conversion combines the velocity of the pressure wave with the travel time to get a depth value.
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The depth conversion command has options to store the Average velocity used to do the depth conversion of each point in the result. You may also choose to store the "instantaneous Instantaneous Velocity". The "Instantaneous Velocity" is computed by looking at the change of average velocity from the velocity model around this a point. For seismic lines the the "Instantaneous Velocity" is the interval velocity of a single sample in the seismic. Storing and visualizing these velocities will make you able to quality control the velocity model used for the depth conversion.
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