Research On Attenuation Method For Shallow Water Multiple In Bohai Bay

The shallow water seismic exploration is great significance to understand the geological structure in Bohai bay.The attenuation of multiple waves in shallow water has always been an unavoidable task for seismic data processing in the Bohai bay.In this paper,the methods of multiple attenuation in shallow water and the research status at domesic and abroad are systematically described,and the development trend of multiple attenuation in shallow water is analyzed.It is recognized that the main methods of multiple attenuation mainly includes filtering and wave equation theory.The existence of multiple disturbs interferes with the information of actual effective wave,affects the quality of processing,and also t the accuracy of data interpretation,Therefore,the effective attenuation of multiple is a subject that we must pay attention to when dealing with shallow water data.Through the study of multiple in shallow water of Bohai bay,the attenuation process of multiple in the shallow water data was studied.First,the multiple and noise between layers are compressed by series deconvolution.Then,the SRME method and SWD method are used to eliminate multiple waves in marine seismic data.SRME can predict all the surface related multiple waves and eliminate them,After the SRME method,the stacked section has obvious effect of removing multiple,clear basement and clear fracture surface.The SWD method can predict multiple waves in shallow water environment,more accurately and effectively eliminate most of the short period multiple waves related to the seafloor.Finally,high precision Radon transform is used to attenuate multiple waves.Combining this method with the traditional de-multiply suppression technique,the shallow water multiples can be attenuated effectively.The actual marine seismic data processing in Bohai bay area shows that: the proposed method can effectively attenuate shallow water multiples,and the combined attenuation process of shallow water multiples is rapidt and simple,The processed seismic data has better amplitude preservation.Through the process of multiple attenuation in the production process,the actual processing results show that,a set of processing flow combining deconvolution,SWD,SRME,high precision Radon domain to remove multiple and residual multiple attenuation is used.In view of the actual marine seismic data processing in Bohai bay area,the proposed method can effectively attenuate shallow water multiples,in future applications also need to consider the multiple points in different regions,appropriate flexible applications.