IMPROVRD WAVE FIELD EXTRAPOLATION TECHNIQUES FOR MULTIPLE WAVE ATTENUATION

In marine geophysical survey, the attenuation of multiple waves is a critical task. Multiple reflections related to water bottom in marine seismic data can be predicted by a combination of numerical wave field extrapolation through the water layer and the estimation of the water bottom multiples. The attenuation of the multiples could be made by subtraction of the predicted wave field from the original record. The proposed method requires almost no any precondition and has a perfect function of amplitude protection. However, there may encounter some drawbacks. For examples, it may behave poorly in the presence of pegleg multiples especially the source side pegleg; and it is weak in overcoming ringing noise. All of these problems can be mitigated by modification of algorithms. In this paper the success of the proposed algorithms has been demonstrated on both numerical experiments and field data processing.