Study Of Tectono-sedimentary Evolution Characteristics Of The P Formation Of Early Cretaceous In The North Slope Of Bongor Basin

Bongor Basin is a Mesozoic-Cenozoic passive rift basin evolved under the influence of shear zone of Central Africa Rift.The basin has experienced early cretaceous rift,strong late cretaceous uplift and reverse,and basin formation in Cenozoic,three structural evolution periods.The basin can be divided into north slope,mid-basin,south rise,and south basin.The main structural formation can be divided into P,M,K,R,B Groups.In this study,we group sedimentary facies,study the structural-sedimentary duplex analysis in typical structural zones to build a structural-sedimentary model and predict potential sand body developing area under the guide of the model.This study is of great significance for deepening the understanding of the sedimentary facies in the study area and exploring the lithologic oil-gas reservoir.The results of the study show that the P Formation are characterized by near-provenance,deep-water,coarse-grain,gravity-flow and consecutive transgression sediments;Baobab north sub-basin has two main provenance systems along the long axis and the short axis;the long axis of east Mimosa sub-basin and the north-east direction of Daniela sub-basin are preferential positions for sand body deposition;P Formation has experienced lake water level drop-early delta development-lake water level rise process.