西湖凹陷平湖斜坡带物源-坡折耦合控砂模式OA北大核心CSTPCD

Pinghu Slope Belt has become one of the important fields of lithologic reservoir exploration in the Xi-hu Sag.Exploration and production have confirmed that the distribution of sand bodies in the Pinghu Formation is complex,and sand body characterization guided by sand-controlling model has become the key to the break-through of lithologic reservoir exploration.Based on the studies on the source system and slope-break zone,the distribution characteristics of sand body under the control of source and slope-break coupling in the target area were summarized in this paper.The characteristics of ravines and heavy minerals indicate that there are three source systems in the target area:the western source and southwestern source of Haijiao Uplift,and the dynamic source of Baoyunting paleo-uplift,which controlled the source of sand material in the target area.Under the con-trol of paleo-uplift,differential activities of faults and sedimentation,three types of slope-breaks developed in the target area,namely faulted slope-breaks,flexural slope-breaks,and depositional slope-breaks,controlled jointly the topographic features of the target area.Source system and slope-break coupling controlled the dynamic pro-cess of sediment from source to sink.Under the joint control of the southwestern source and the dynamic source of Baoyunting Uplift,the development of mixed-source sand body accretion is dominant in the lower member of Pinghu Formation.Under the main control of the source of the western Haijiao Uplift,the single-source-reforma-tion sand-controlling mode restricted by flexural slope-break is dominant in the middle member of Pinghu Forma-tion.Under the main control of the depositional slope break,the transitional sand-controlling mode of gentle slope was developed in the upper member of Pinghu Formation.