Sedimentary Facies And Reservoir Characteristics Of The Paleogene In Shenxian Depression

Using relative data such as seismic, well drilling/logging, core sampling and referringto former study achievements of other researchers, this paper examines the Sedimentaryfacies and reservoir features of the Paleogene in Shenxian Depression.The research area had developed3provenance depositional system and5types ofsedimentary facies. The Paleogene sedimentary facies of Shenxian depression issubdivided into15subfacies and more than20microfacies. Sendimentary facies developedin each period are characterized by inheritance, and the sedimentation centre migratedfrom Southwest to Northeast bottom-up.Through the methods of core observation, core sampling and other experimentalanalysis, it is found that the Paleogene reservoirs of Shenxian depression had undergonesome diageneses like compaction, cementation and dissolution. The diagenetic stage ofreservoirs is from B stage of early diagenetic period to B stage of late diagenetic period.It is observed that reservoirs in this area are mainly Type I—III, and Type IV reservoiris mainly developed below fourth member of Shahejie Formation. Types of sandstonebodies, diagenic metamorphism and tectonic movement are controlling factors which causethe physical property differences among various kinds of sedimentary microfacies.