Patent attributes
A method for seismic surveying includes deploying a group of vertically sensitive seismic particle motion responsive sensors at each of a plurality of geodetic survey positions. The groups each include at least two sensors spaced apart by a first selected horizontal distance. The groups are separated from each other by a second selected distance larger than the first distance. Signals detected by each of the sensors resulting from actuation of a seismic energy source are recorded. At least one of an in-line and a cross-line component of a gradient of the vertical component of the seismic wavefield is determined at each group location by determining a difference between the signals detected by each sensor in a respective group.