| 摘要 |
Method for processing seismic data to correct for errors caused by variation in water conditions. In one implementation, the method may include (a) applying a dip correction to a plurality of observed water bottom reflection times using a model water velocity and an estimate of geologic dip; (b) applying a normal moveout (NMO) correction to the dip corrected observed water bottom reflection times using the model water velocity; (c) applying a common mid point ("CMP") bin centering correction to the NMO corrected, dip corrected observed water bottom reflection times using the model water velocity and the estimate of geologic dip; (d) solving for Deltas<SUB>i</SUB>, which is an estimate of the difference in slowness between the observed water bottom reflection times and the water bottom reflection times that would have been observed had the water velocity been the same as the model water velocity; (e) solving for an estimate of observed water velocity based on s<SUB>obs,i</SUB>=s<SUB>m</SUB>+Deltas<SUB>i</SUB>, where s<SUB>obs,i </SUB>is an estimate of observed slowness and s<SUB>m </SUB>is defined as the model slowness; (f) layer replacing the observed water bottom reflection times using the estimate of the observed water velocity and the model water velocity; and (g) repeating steps (a) to (f) using the layer replaced observed water bottom reflection times until the changes in the estimate of observed water velocity approach zero.
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