TRAPPED WATER BOTTOM MULTIPLE AND PEG-LEG MULTIPLE SUPPRESSION FOR OCEAN BOTTOM SEISMIC DATA

The invention is a method for removing trapped water bottom multiples (figur e 2, item 19), receiver side peg-leg multiples (13), and source side peg-leg multiples (15) from dual sensor (figure 1, item 6), OBC (7) data, where the data includes both pressure signals and velocity signals. The pressure and velocity signals are compared to determine any polarity reversals between th em (figure 3, item 21). Polarity reversals are used to identify and separate up - going and down-going wavefields in the pressure and velocity signals (22). A matching filter is applied to a portion of the velocity signal where polarit y reversals exist (24). The down-going wavefield is then estimated by calculating the difference between the portion of the velocity signal where polarity reversals exist and the portion of the pressure signal where polari ty reversals exist and applying a scaling factor to the result (26). An attenuated up-going pressure wavefield is then determined by combining the estimated down-going wavefield and the pressure signal (28).