Quantitative analysis of source-to-sink system controls on sand-body distribution of the Paleogene in Chengbei low uplift and surrounding areas,Bohai Bay Basin

In this paper,Chengbei low uplift and the surrounding areas is taken as a whole source-sink system. On the basis of this,utilizing logging,well logging,rock core and 3D seismic data,analysis of sedimentary system types and features of Chengbei low uplift,the quantitative relationship of elements in source-to-sink system is discussed. The results indicate that lithology of basement rock in the Chenbei low uplift is Mesozoic clastic rock during the Paleogene,thin section and the geophysical response data in this study,basement rock is subdivided into nine drainage systems. The corresponding transport pathways including fifteen paleo-valleys and two fault-troughs are identified in the Chenbei low uplift. The paleo-valleys are further subdivided into V shape,U shape,W shape. Fan deltas,semi-deep lacustrine and deep lacustrine is developed in steep slope zone of Chengbei low uplift,which presents isolated lob shape in plane distribution. Braided river delta,shore-shallow,semi-deep lacustrine and deep lacustrine is mainly developed in gentle slope belt,which is featured with wide and continuous plane distribution and superimposed vertical distribution. The characterization of elements in source-to-sink system indicates that volume of depositional systems is closely related to drainage area,length,width,width/length of paleo-valleys. Coupling mode of the source-to-sink system suggests that effective source area controls the size of sedimentary system;sand transporting path controls sedimentary distribution direction and shape.