Study On Formation Mechanism And Development Countermeasures Of Remaining Oil In Ordovician Buried Hill Reservoir Of Renqiu

The Ren'ao buried hill reservoir is located in the northern part of the Renqiu buried hill zone.The planar shape is a fan shape that opens to the northeast,and the structural shape is a monoclinic structure inclined to the northeast.The Ren'ao buried hill reservoir is a thick layered weak edge water.Low saturation oil reservoir.Ren'ao buried hill reservoir has complex geological characteristics,developed faults and complex distribution,general injection and production development,and block distribution in high water-cut areas.The static method is used to analyze the geology of different oil groups and the development correspondence is insufficient,revealing faults,The influence mechanism of the barrier on the development status is difficult.Therefore,understanding the influence of reservoir geological characteristics on the existing remaining oil and water-flooded degree and understanding the formation mechanism of remaining oil will provide important theoretical guidance for the subsequent development and management of Ren'ao buried hill reservoirs.This thesis takes the Renqiu Ordovician buried hill reservoir as the research object,combines dynamic and static characteristics to understand geology and development correspondence in depth,and studies the types and distribution characteristics of the reservoir,barriers,and faults in Ren'ao buried hill reservoirs.The role of faults in the process of reservoir development and accumulation,as well as their influence on remaining oil enrichment,to find out the reservoir flooding law,remaining oil enrichment mechanism and remaining oil distribution characteristics,and on this basis,aim at remaining oil distribution.Laws and enrichment models formulate next-step strategies for tapping the potential.Based on the existing stratigraphic division methods in the study area,the types and distribution characteristics of Ren'ao buried hill reservoirs,barriers,and faults are given and a distribution map is drawn;the research shows that the barriers enrich the crude oil.The influence of faults and remaining oil accumulation is mainly manifested in vertical and lateral sealing.The influence of faults on remaining oil enrichment areas is mainly manifested in the formation of top crude oil enrichment under the combined action of faults and denuded surface barriers,and between faults and oil groups or oil.The accumulation of crude oil in the cambium under the joint action of the internal barriers of the reservoir unit;four remaining oil enrichment modes under the joint action of faults and barriers are given: unconformity surface + barrier control type;buried hill fault + unconformity.Face + barrier control type;buried hill inner fault +unconformity face + barrier control type A(fault fall reverse tendency);buried hill inner fault + unconformity face + barrier control type B(fault fall direction along trend);Put forward the remaining oil development countermeasures of the Renao buried hill reservoir and the EOR recommendations that can be considered in the future of the study area,including the top gas injection method,multi-well linkage asynchronous water injection,and active water flooding.