Method for Imaging a Sea-Surface Reflector from Towed Dual-Sensor Streamer Data

A pressure wavefield and a normal velocity wavefield measured on a smoothly shaped acquisition surface by towed dual-sensor marine seismic streamers are decomposed into up-going and down-going pressure and particle velocity components on an observation level between the acquisition surface and a sea surface of undetermined shape. The up-going and down-going pressure and particle velocity components are extrapolated iteratively in steps from the observation level toward the sea surface. An image point and a reflection coefficient of the sea surface at the image point are determined from the iteratively extrapolated up-going and down-going pressure and particle velocity components.