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geophone offset

1. n. [Geophysics]
In surface seismic acquisition, the horizontal distance from source to geophone. In a vertical seismic profile, geophone offset is the horizontal distance between the source and the wellhead or the surface projection of the geophone in the case of a deviated well. Offset between seismic source and receiver creates a delay, or moveout, in the arrival time of a reflection that can be corrected before stacking and can be used to determine velocity.