Control Of Strike Slip Associated Structures On Hydrocarbon Accumulation In Southern Part Of Liaozhong Depression

Liaozhong depression is one of the rich hydrocarbon depressions in the Bohai sea area.As an important part of oil and gas exploration in Liaodong Bay depression,Liaozhong depression is a favorable place for oil and gas accumulation,and many large and medium-sized oil and gas fields have been discovered continuously,which shows great potential for exploration.There are many large north-east strike slip faults and regulating faults in the southern part of Liaozhong depression.A variety of structural deformation is associated with the strike slip displacement.These strike slip associated structures are closely related to the distribution of oil and gas.However,the study on the control of strike slip associated structures on hydrocarbon accumulation is still not perfect.In this paper,core data,logging,well logging,seismic and analytical data are comprehensively utilized.The strike slip associated structures in Liaozhong South depression and their control over oil source,fault and reservoir are analyzed.Based on the study of the background of hydrocarbon accumulation in strike slip associated structural belts,the typical reservoirs such as LD21-2,LD27-2 and LD16-3S are dissected.Research holds that the strike slip conversion structure is the compression stress concentration zone,which controls the formation of structural traps.The type of transition zone controls the type and scale of traps.The extension background controls the development of source rocks,and the stratified waters control the enrichment of organic matter.The development model of source rocks in the study area includes two types: sedimentary model of sedimentary deep-water temperature stratified source rocks and sedimentary model of salinized lake basin salinity stratified water source rocks;transportability of compression-torsion fracture under extended strike slip background The distribution of oil and gas is controlled to the structural position,interval and scale,and the fault sealing control the reservoir oil and gas enrichment.Through the analysis of typical oil and gas reservoir anatomy and failure(inefficient)wells,the superimposed oil and gas accumulation model,the gentle slope zone-deep oil and gas accumulation model and the mid-salt arching of the extensional strike slip tectonic belt in the central and southern Liaoning With the multi-layer oil and gas accumulation model,the research results can provide reference for the next exploration practice.