Abstract:In marine seismic exploration, due to strong impedance difference at the sea bottom, serious peg-leg multiples are generated between sea bottom and high velocity layers or scatters just under the bottom. This kind of peg-leg multiples is very difficult to remove because they have no specific characteristics. Based on seismic interferometry, we propose in this paper an approach for sea bottom related peg-leg multiple removal. First, we introduce the principle of seismic interferometry based on reciprocity theory, and illustrate its approximate conditions and expression in inhomogeneous media. Then we construct bottom-related peg-leg multiples with sea bottom primary reflections and under-bottom reflections. This data-driven multiple removal approach overcomes velocity dependent as common focus point (CFP) has, and has higher computation efficiency than inverse scattering series (ISS). Both Sigsbee2B model test and real data example show that the proposed approach can better remove bottom-related peg-leg multiples. Furthermore, prestack depth migration artifacts disappear after bottom peg-leg multiple removal by this approach.
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