Decomposition of multicomponent sea‐floor data into upgoing and downgoing P‐ and S‐waves

Abstract

A method for decomposing multicomponent sea‐floor measurements into upgoing and downgoing P‐ and S‐waves is presented. We assume that a marine survey employing a marine source in the water layer is conducted over a plane‐layered medium. From recordings of the pressure just above the sea floor and the particle velocity vector just below the sea floor, decomposition filters can be determined by plane‐wave analysis. The decomposition filter coefficients depend on the P‐ and S‐wave velocities and the density at the sea bottom. We show how to decompose the multicomponent measurements into upgoing and downgoing P‐ and S‐vertical traction components, vertical‐particle velocity components, and horizontal particle velocity components. The decomposition filters are applied with good results to synthetic data modeled in a plane‐layered medium.