Patent ID: 6865488

Claim:
A method for recording and processing vibratory source seismic data, the method comprising: (a) generating a cascaded sweep sequence comprising N sweep segments that are either concatenated or overlapping sequentially, where N is equal to or greater than 2, said N sweep segments being substantially identical, except that the initial phase angles of said N sweep segments are progressively rotated by a constant phase increment of about 2 m π/N radians where m is an integer and |m|>1; (b) using said cascaded sweep sequence to drive at least one vibratory source thereby propagating a seismic wave into the earth at a selected location; (c) recording a groundforce signal associated with said seismic wave; (d) recording at least one reflection signal from a location within the earth responsive to said seismic wave; and (e) using said recorded groundforce signal for processing the signal recorded to produce a processed signal.