Notch effect and frequency compensation of dual-sensor OBC data in shallow water

Abstract

Reverberation is significant in shallow water and produces obvious notches in OBC spectra. It also degrades the quality of sections and increases the difficulty of processing and interpretation. This article presents the relationship between notch, shooting depth, and seabed depth based on the seismic convolution model. Forward modelling based on wave equation theory is used to verify this relationship. Dual-sensor summation is applied to suppress receiver-side multiples and remove notches according to the opposite response of geophones and hydrophones to down-going wave fields based on a detailed analysis of the OBC technique. The good results obtained in practical applications reveal the effectiveness of this method.

Keywords

reverberation / notch / shooting depth / dual-sensor

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