In
geophysics,
Vertical Seismic Profile (VSP) is a technique of
seismic measurements used for correlation with surface seismic data. The defining characteristic of a VSP (of which there are many types) is that either the energy source, or the detectors (or sometimes both) are in a borehole. In the most common type of VSP,
Hydrophones, or more often
geophones or
accelerometers, in the
borehole record reflected seismic energy originating from a seismic source at the surface.