Research On Features Of Stratigraphic Framework And The Distribution Of Reservoir And Restraining Barrier In Shuguang Inner Buried Hills Of Liaohe Basin

In view of the unclear understanding of the strata attribution and the distribution characteristics of reservoir and restraining barrier in Shuguang buried hills,this paper applies the methods of paleontological stratigraphy,isotopic stratigraphy and rock stratigraphy to the fine division and comparison of the inner strata in buried hills,and establishes the internal stratigraphic framework at the same time.It uses multiple seismic information and seismic inversion method to predict the buried hill reservoir and seperation layers,so as to make clear the Proterozoic,Paleozoic favorable reservoir distribution and its control on oil and gas distribution.The results show that the target layers in the study area can be subdivided into 7 inner layers : Yeli formation,Fengshan formation,Changshan formation,Gushan formation,Qingbaikou system,Gaoyuzhuang formation and Dahongyu formation.Through the analysis of the inner stratigraphic framework of the whole area,it can be seen that except the Qingbaikou strata,the distribution range of the inside strata is small and discontinuous,which is mainly concentrated in the northwest and central regions of the study area.In the study area,the effective reservoir space is pore and fracture.Based on the analysis of reservoir physical properties prediction map,it can be seen that near the fault and near the buried hill are favorable areas for the development of fractures and porosity.The prediction results of reservoir thickness based on curve reconstruction and wave impedance inversion show that the Paleozoic slate thickness is small and the distribution is not continuous,the Proterozoic slate thickness is relatively large and the local continuity is better.According to the characteristics of slate,divide the slate roughly into four types.The statistical analysis of the lithology thickness above the oil test level in the study area shows that the lithology is not the main factor to control the reservoir performance.The secondary pore development is the main factor to control the reservoir performance,so the reservoir's control effect on the distribution of oil and gas is mainly the development of the reservoir pore.Regional caprock distribution-controls macro distribution of oil and gas.Inside mudstone caprock distributes controls oil and gas specific enrichment horizon.