A method for determining seismic sensor depths below a free-surface, comprising:
- accepting as input to a computer measurements of seismic signals made by a plurality of seismic sensors disposed at selected depths below the free-surface, the seismic signals resulting from actuation of a seismic energy source disposed at a selected depth with reference to the free-surface;
- defining a depth increment and a range of sensor depths for correlation of signals from each of the plurality of seismic sensors;
- in the computer, extrapolating the input seismic measurements to each depth increment in the range;
- and
- in the computer, determining a depth of each seismic sensor by correlating the seismic signal measurements with depth-extrapolated measurements of the seismic signal measurements.