Research And Application Of Seismic Acquisition Method In Paralic Zone Of North Jiangsu-South Yellow Sea

The South Yellow Sea basin is a superposed basin of Cenozoic,Mesozoic and Paleozoic,and the sedimentary strata of the basin are composed of three sets of tectonic beds of Paleozoic,Mesozoic and Cenozoic respectively from bottom to top.The accumulative thickness of the strata is more than 5000 m,which has good oil and gas prospects and is an important potential area of oil and gas exploration.However,no major breakthrough has been achieved so far due to the low degree of exploration.In particular,the distribution of the main pretertiary sequences in the south Yellow Sea is not clear,which needs to be compared with the seismic data on land to solve the problem of collecting and processing the seismic data in the intertidal data blank area.In this paper,the technical operational difficulties in the research area have been clarified based on the analysis of the previous collection methods and the quality of previous data in the research area and according to the detailed on-site scouting of the research area,and corresponding measures are made as well.Through the geometry demonstration and optimization,reasonable geometry parameters are designed to improve the energy and signalto-noise ratio of deep weak reflected signals.Through the study of the airgun shooting parameters design and optimization technology,and according to the geological task of twodimensional seismic exploration in the paralic area of North Jiangsu-South Yellow Sea and the change of water depth in the work area,clear requirements for airgun shooting parameters are put forward,such as volumn,pressure and the property of airgun wavelet.According to the analysis of interference wave development in the paralic area of North Jiangsu-South Yellow Sea,through the in-depth study of dual-sensor recording technology in OBC(Ocean Bottom Cable)exploration,the influence of ghost reflection on seismic data quality and the necessity to apply dual-sensor recording technology in this area are analyzed systematically.In order to ensure the quality of seismic data,the comprehensive on-site quality control technology is studied in this paper,and the combined application of acoustic and first break secondary positioning method,the real-time quality control of air gun technical specification and the realtime monitoring technology of the seismic acquisition data on instrument site are proposed and applied.In general,through the research of this paper,a targeted acquisition method for the acquisition technology and operational difficulties in the paralic area of North Jiangsu-South Yellow Sea has been formed,and a good application effect has been achieved in the project.At the same time,the research results of this paper have certain reference significance and popularization value for similar seismic acquisition projects.