Study On The Main Controlling Factors Of Oil And Gas Accumulation In The Fourth Member Of Shahejie Formation In Huanxiling Oilfield,Liaohe

The Dujiatai reservoir is the main reservoir in shasiduan oilfield of Liaohe Xingling Oilfield.The purpose of this study is to find the potential area and increase oil and gas production by analyzing the main controlling factors of oil and gas accumulation and summarizing the rules.Through this study,the following research results have been obtained: The sedimentary system in the whole region was studied by single well facies analysis.The distribution and development of reservoir are realized by reservoir inversion technique.Combined with the characteristics of reservoir distribution,the main controlling factors of oil and gas accumulation in Sha4 section of Xingling Oilfield are systematically studied by using sequence stratigraphy,seismography,geostatistics and other methods,combined with drilling,logging,logging,oil test and production data.Through this study,four conclusions are drawn :(1)the sha-4 section in the study area is characterized by complex structure and many faults,with two groups of faults mainly developed,and the north-to-west faults represented by F1 fault are mainly monoclinal and fault-nose faults.(2)The sedimentary system is fan delta-lacustrine deposition,and the provenances are mainly from the north,west and southwest,forming the sedimentary characteristics of simultaneous supply of multiple provenances;The subaqueous distributary channel in fan delta is the main sedimentary microfacies belt in the whole area.Two sedimentary belts with the characteristics of thick wedge-like structure in the west and thin in the east are formed with "high barrier belt" as the boundary.(3)The reservoir distribution in Sha-si-member is mainly formed under the dual control of paleogeomorphology and multi-phase cycles,and generally the distribution range of reservoirs is gradually expanded from bottom to top.(4)The oil-water relationship in the study area is complex and mainly consists of structural-lithologic oil and gas reservoirs.The oil and gas reservoirs are mainly distributed in the areas of high barrier zone and lower step,oil and gas accumulation is controlled by trap,fault,sedimentation and sand body.Trap provides a place for oil and gas accumulation,and fault provides a channel and block for oil and gas migration,the underwater distributary channel deposits provide favorable reservoir space for oil and gas accumulation,and the thickness of sand body controls the degree of oil and gas enrichment.