Patent ID: 7957906

Claim:
A method for geophysical prospecting, comprising: disposing pressure and vertical velocity sensors in a seismic streamer in a body of water; responsive to signals received from the pressure and vertical velocity sensors, calculating seismic traces representing physical wavefields in the body of water incident on the sensors; and transforming the seismic traces to produce vertical velocity traces representing vertical velocity wavefields with attenuated low frequency noise, the transforming comprising: determining a calculated vertical velocity sensor trace from a recorded pressure sensor trace; determining a constructed vertical velocity sensor trace as a linear combination of the calculated vertical velocity sensor trace and a recorded vertical velocity sensor trace, using a mixture coefficient as a proportionality constant; determining an upgoing pressure wavefield component trace as one half of a difference of the recorded pressure sensor trace and the constructed vertical velocity sensor trace, as a function of the mixture coefficient; determining an error in the upgoing pressure wavefield component trace by propagating errors in the recorded pressure sensor trace and constructed vertical velocity sensor trace terms; and determining a value of the mixture coefficient that minimizes the error in the upgoing pressure wavefield component trace; and recording the constructed vertical velocity sensor trace.