Seismic Sedimentology Analysis Of River Delta Under Sparse Wells Conditions

As a large Cenozoic sedimentary basin,the pearl river mouth basin is rich in oil and gas resources.The ancient pearl river delta is a sedimentary system closely related to oil and gas in the basin.The Zhujiang formation is the most complex stratigraphic unit of sedimentary facies in the neogene system of Huizhou sag.In the pearl river estuary basin,there are few Wells drilled and the well pattern is sparse,but the seismic data is abundant.In this case,the seismic sedimentological method must be used to analyze the delta sedimentary system and then discuss the relationship between the delta and oil and gas.Based on the collected literature at home and abroad in the study area and on the basis of predecessors' research results,huizhou sag in pearl river mouth basin of the pearl river formation as the research object,using seismic configurations,90 degree phase conversion,seismic attribute analysis,strata slice technology and frequency division interpretation of seismic sedimentology study method,determines the research area of the pearl river delta sedimentary period set of planar distribution characteristic and evolution law of research by the following:1,The structure of the seismic section the reflection is mainly through internal reflection structure and external form characterized the characteristics of sedimentary facies,such as the group of the pearl river delta plain seismic reflection configurations in parallel and the parallel sheet more reflection seismic facies mainly,partially visible angle oblique progradation imbricated reflection seismic facies,and delta front is characterized by the parallel oblique progradation and low angle oblique progradation reflection.2.With 90 degree phase conversion,seismic attribute analysis,strata slice technology and frequency division interpretation technology to determine the time of each sequence unit in the study area flat distribution of sedimentary facies,such as delta sedimentary lobate distribution characteristics,and tidal sand ridge is a commonly zonal characteristics significantly.3.The distribution of the sedimentary system of the Zhujiang formation in the study area is affected by the rise and fall of sea level.With the gradual rise of global sea level,The delta deposits of the Zhujiang formation in Huizhou depression of the pearl river mouth basin show a trend of gradually increasing from the initial stage to gradually retreating later.