Study On The Reverberation Suppression And Migration Of Marine Seismic Data

The requirements of marine resources investigation and exploration and development for marine seismic technology are increasing.Marine multi-component seismic acquisition has been widely used,including single component hydrophone streamer acquisition,seabed four component OBC,OBN,OBS acquisition.Marine seismic data contains a variety of interferencesand effective reflection.One of the main interference signals is the reverberation reflection of seismic wave in the sea water layer,which seriously affects the effective frequency band and reduced signal-to-noise ratio of the seismic data.In this paper,a series of research on the methods of reverberation suppression and migration imaging of marine seismic data are carried out,in order to improve the accuracy of subsequent data processing andinterpretationOn the basis of fully investigation and study of the existing research results at home and abroad,aiming at the formation mechanism of multiple waves in seawater,this paper first introduces the acquisition principle of dual detector and the frequency response characteristics of dual detector.The travel time,phase and frequency characteristics of direct wave,primary reflection and seafloor reverberation on X,Z and P components are analyzed by using the model data.And carry on the research of PZ superposition method and design dual detector matching window,and verify it in model data and actual data to get good results;furthermorethe feasibility of applying PZ stack to noise suppression on X and Y components is discussed.The last oneon the basis of VSP migration imaging,this paper tests the parameters of landmark migration aperture,the angle between the extension direction and the vertical direction of aperture depth,and the resection rate of NMO correction.And it is applied to ocean multi-component data.After wave field separation of P-wave and converted S-wave,the model data migration imaging has good adaptability.This paper also tests and analyzes the actual data.On the basis of RT rotation,spherical diffusion compensation,abnormal amplitude suppression,predictive deconvolutionand other preprocessing for the actual streamer and OBS Data,the two acquisition methods for suppressing reverberationare compared;1)In the streamer data,the seafloor reverberation is divided into short period and long period,and the methods of DWD and SRME are applied to suppress them respectively;2)PZ stack is used to suppress reverberation waves for OBS Data.The test results show that: in order to obtain good suppressing effect,the streamer data processing needs to use DWD and SRME;on the basis of the separation of the vertical and horizontal wave fields of the OBS Data,the PZ double check stack can suppress the sound better,but there are still multiple waves in the up traveling wave.