Methods of band-equalizing seismograms

Claim 1

A METHOD PRODUCING FROM SEISMIC SIGNALS GENERATED IN RESPONSE TO SEPARATE INPUT SEISMIC ENERGIES APPLIED AT DIFFERENT SHOP POINTS IMPROVED SEISMIC SIGNALS THAT WOULD BE GENERATED IF ALL WERE PRODUCED FROM A REFERENCE INPUT SEISMIC ENERGY, COMPRISING THE SEPTS OF: (A) A GENERATING A FIST SIGNAL HAVING AN AMPLITUDE-FREQUENCY SPECTRUM BA(W) REPRESENTATIVE OF THE AMPLITUDE-FREQUENCY SPECTRUM OF ONE OF THE INPUT SEISMIC ENERGIES, (B) GENERATING A SECOND SIGNAL HAVING AN AMPLITUDE FREQUENCY SPECTRUM B''(W) REPRESENTATIVE OF THE REFERENCE INPUT SEISMIC ENERGY, (C) COMPARING SAID FIRST AND SECOND SIGNALS TO PRODUCE A FILTER WHOSE IMPULSE RESPONSE IN THE FREQUENCY DOMAIN IS CHARACTERIZED BY AN AMPLITUDE-FREQUENCY SPECTRUM OF B''(W)/BA(W), AND (D) APPLYING TO SAID FILTER THE SEISMIC SIGNAL GENERATED IN RESPONSE TO SAID ONE OF SAID INPUT SEISMIC ENERGIES TO PRODUCE AN IMPROVED SEISMIC SIGNAL.