Extracting sv shear data from p-wave marine data

Abstract

A system and method of processing seismic data obtained using a plurality of towed single-component receivers in a marine environment is described, the towed single-component receivers configured to measure compressional P waves. The method comprises retrieving seismic data from a storage device, the seismic data comprising P-P data and shear mode data, wherein the P-P data and shear mode data were both received at the towed single-component receivers configured to measure compressional P waves to generate the seismic data. The method further comprises processing the seismic data to extract SV-P shear mode data and generating shear mode image data based on the extracted shear mode data.

1 .- 10 . (canceled) 
     
     
         11 . A method of generating a shear mode image from marine P-wave seismic data acquired with a plurality of towed single-component P-wave sensors, comprising:
 retrieving from a storage device seismic data generated by a source and received by the towed single-component P-wave sensors, the data comprising SV-P mode data;   extrapolating wavefields represented by the seismic data downward to computationally create virtual sources and virtual receivers on a seafloor in the vicinity of an area imaged by the seismic data; and   processing the extrapolated wavefields to generate shear mode image data.   
     
     
         12 . The method of  claim 11 , wherein the SV-P mode data is a result of a downgoing P wave from a towed P wave source which upon contact with the seafloor generates downgoing SV shear wave modes directly at the point of contact of the P wave with the seafloor at the seafloor surface. 
     
     
         13 . The method of  claim 12 , wherein the seismic data was received at the towed P-wave sensors as they were being towed, the sensors disposed well above the seafloor within the water column without the use of multi-component geophones. 
     
     
         14 .- 23 . (canceled)