Sea imaging from a dual-sensor streamer data : A feasibilty study

Sea surface profile and reflection coefficient estimates are vital input parameters to various seismic data processing applications. The common assumption of a flat sea surface when processing seismic data can lead to misinterpretations and mislocations of events. A new method of imaging the sea surface from decomposed wavefields is presented. Wavefield separation is applied to the data acquired by a towed dual sensor streamer containing collocated hydrophones and geophones to obtain the up- and down-going wavefields of the related sensors. The up- and down-going wavefields of a given sensor are extrapolated to the sea surface where an imaging condition is applied in order to obtain the sea surface profile. The image points values obtained at the sea surface are the reflection coefficient values of these points. Ray tracing and finite difference methods are used to generate different controlled data sets employed in this feasibility study to demonstrate the imaging principle and to test the image accuracy. Finally, a first field data example of a marginal weather line from the Norwegian North-Sea is presented