Multiple attenuation and P/S splitting of multicomponent OBC data at a heterogeneous sea floor

One of the benefits of dual-sensor (hydrophone and geophone) recordings in ocean bottom cable (OBC) experiments is that hydrophone data and geophone d ata can be combined to attenuate receiver-side reverberations in both data types or combined to split geophone data into upgoing P-and S-waves, albeit after applying appropriate scaling filters. Most of the formulae currently used to compute these scaling filters assume, sometimes implicitly, that t he sea floor is horizontally flat. We present a generalization of these for mulae to cases where the sea floor is arbitrarily heterogeneous. Heterogene ities can be due to the topography of the sea floor as well as laterally va rying medium parameters along the sea floor. The novelty here is that our d erivations are based on the elastodynamic representation theorem instead of plane wave decomposition. For the particular case where the medium paramet ers are constant along the receiver spread at a dipping sea floor, the resu lting scaling filters are explicit and identical to those obtained by plane wave decomposition analysis. The results of our formulation can be used either for multiple attenuation or P/S splitting or both. (C) 2000 Elsevier Science B.V. All rights reserve d.