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walk-above vertical seismic profile

Diagram of VSP configurations
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1. n. [Geophysics]
A type of vertical seismic profile to accommodate the geometry of a deviated well; sometimes called a vertical incidence VSP. Each receiver is in a different lateral position with the source directly above the receiver for all cases. Such data provide a high-resolution seismic image of the subsurface below the trajectory of the well.
Alternate Form: walk-above VSP