Seismic Data Acquisition And Processing Research For Mesozoic And Paleozoic Exploration In South Yellow Sea

The bottom interface T2 of the South Yellow Sea Neogene is a regional strong reflection interface with shallow buried depth,wide distribution,large reflection coefficient and difficult transmission of seismic waves.Therefore,high quality sections can not be obtained for seismic exploration of underlying strata,so it is necessary to study the corresponding methods.In this paper,the geological and geophysical characteristics of South Yellow Sea are analyzed,and the unconformity surface T2 is deeply understood.At the same time,the methods and difficulties of collecting and processing South Yellow Sea seismic data are studied.It is recognized that the focal point of rich low frequency and large volume is the key to break through T2 shielding,and the attenuation of interference derived from multiple is the guarantee of obtaining high quality profiles.On the basis of the above understanding,the seismic exploration design is carried out based on the imaging below T2 of strong reflection interface.Firstly,the advantages of large capacity seismic source are determined by comparing the old data.Then the Nucleus source wavelet simulation system of PGS is used to simulate various configurations of wavelet.Finally,the low frequency energy is sufficient,the high frequency energy is wide,the whole reflection energy is wide,the over/under source configuration is obtained,and the receiving system is also studied systematically.Finally,the configuration and acquisition parameters of double cable wide line receiving are determined.The field data are collected by using the above exploration design,and the quality analysis and processing of the actual collected data are carried out.According to the characteristics of South Yellow Sea data,the methods of multiple attenuation are emphatically studied in the processing.Experiments on how to make better use of wide line data in attenuation multiple waves and migration are carried out,and a set of processing flow is summarized.Finally,the new and old sections are compared and analyzed.This research synthesizes the two aspects of acquisition and processing,and forms a set of methods of collection and processing,which provides a reference for the future exploration work.