| 摘要 |
A METHOD FOR SPECTRAL BALANCING OF NEAR-AND FAR-OFFSET SEISMIC DATA, WHEREBY VELOCITY AND OFFSETS ARE DETERMINED FOR THE SEIMIC DATA. FIRST, AN NMO STRECTH COMPENSATION FILTER IS CREATED BY THE FOLLOWING STEPS. A FREQUENCY SPECTRUM OF THE NEAR-OFFSET SEISMIC DATA IS ESTIMATED AND A STRECH FACTOR B IS CALCULATED FOR THE FREQUENCY SPECTRUM, USING THE VELOCITY AND THE OFFSETS. A STRECHED FREQUENCY SPECTRUM OF NEAR-OFFSET SEISMIC DATA IS CALCULATED, BASED ON THE STRETCH FACTOR B. THE FREQUENCY SPECTRUM OF NEAR-OFFSET SEISMIC DATA IS DIVIDED BY THE STRETCHED FREQUENCY SPECTRUM OF NEAR-OFFSET SEIMIC DATA, GENERATING A FIRST FREQUENCY RESPONSE FILTER. HIGH FREQUENCY GAIN IS LIMITED IN THE FIRST FREQUENCY RESPONSE FILTER, GENERATING A FIRST GAIN-LIMITED FILTER. THE FIRST GAIN-LIMITED FILTER IS CONVOLVED WITH A LOW PASS FILTER, GENERATING THE MNO STRETCH COMPENSATION FILTER. THEN THE NMO STRECTH COMPENSATION FILTER IS APPLIED TO THE SEISMIC DATA. SECOND, A RELATIVE Q COMPENSATION FILTER IS CREATED BY THE FOLLOWING STEPS. A DIFFERENCE IN AMPLITUDE LOSS BETWEEN THE NEAR-AND FAR-OFFSET SEIMIC DATA IS CALCULATED USING THE VELOCITY AND THE OFFSET. A FREQUENCY GAIN IS CALCULATED, BASED ON THE DIFFERENCE IN AMPLITUDE LOSS. A SECOND FREQUENCY RESPONSE FILTER CREATED, BASED ON THE FREQUENCY GAIN. HIGH FREQUENCY GAIN IS LIMITED IN THE SECOND FREQUENCY RESPONSE FILTER, GENERATING A SECOND GAIN-LIMITED FILTER. THE SECOND FREQUENCY RESPONSE FILTER, GENERATING A SECOND GAIN-LIMITED FILTER. THE SECOND GAIN-LIMITED FILTER IS CONVOLVED WITH A LOW PASS FILTER, GENERATING THE RELATIVE Q COMPENSATION FILTER. THE RELATIVE Q COMPENSATION FILTER IS APPLIED TO THE SEISMIC DATA.(FIG 5A,FIG 5B)
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