Study On Damoguaihe Formation Sedimentary Facies And Its Control Action On Oil And Gas In Beier Depression

This paper is based on the study of Damoguaihe Formation in Beier Depression,Hailaer Basin.On the basis of careful study of relevant literature and reference to existing research results,Using the Geophysics,reservoir geology,petroleum geology,sedimentary petrology and other related disciplines of knowledge theory,Through the analysis and test data obtained,the comprehensive analysis and utilization of the core sample observation record and log data,The sedimentary facies types,the distribution characteristics of sand bodies,the hydrocarbon accumulation factors and the main controlling factors are analyzed.Finally,based on the above work,the control function of the relative oil and gas is analyzed.In the period of the first member of Damoguaihe Formation in Beier depression,the lake has a wide distribution range,which is dominated by lacustrine deposits,and the sedimentary area of the delta is relatively small.During the period of the second member of Damoguaihe Formation,the area of the lake was reduced,and the scale of the delta deposition became larger.Through comprehensive consideration of the sedimentary facies marks,such as sedimentary rock color,sedimentary structure and logging facies mark,Combining single well facies and associated well facies analysis,it is considered that the study area mainly developed two facies types of delta facies and lacustrine facies,five Subfacies types of the meandering river delta front,before the meandering river delta,meandering river delta,shallow lake,semi deep lake and deep lake facies,ten microfacies types of mouth bar,Distal bar,Sheet sand,Underwater distributary channel,Distributary channel,Split Bay,Under water diversion Bay Deep lake mud,Former delta mud and Gravity flow.Based on the sedimentary microfacies analysis,the results of previous studies,combined with a large number of data obtained from the field,the oil and gas accumulation factors and main controlling factors of oil source condition,Source of oil and gas,Migration pathway and Reservoir forming model were analyzed.Through the analysis we think that the oil and gas of Damoguaihe Formation mainly from Nantun Formation and first member of Damoguaihe Formation,The reservoir is the second member of Damoguaihe Formation,and its Rock type is Mainly sand conglomerate.The first member of the Yimin formation is Cap layer.Oil and gas migration channels are mainly unconformities and faults,Fluid potential affects the migration of oil and gas,The raw reservoir cap combination is lower storage on the storage type,The distribution of effective source rocks controls the distribution of oil and gas,Oil and gas are gathered near the hydrocarbon generating center through short distance migration,the sedimentary microfacies influence the accumulation of oil and gas by controlling the distribution of favorable reservoirs.Different sedimentary microfacies development different Sediments,Dark mudstone developed in lake environment will become hydrocarbon source rocks become of its rich organic matter content,Sometimes,its will become Cap layer become of its extremely low porosity and permeability.Sand bodies developed in delta environment will become favorable storage sites.Sedimentary facies control hydrocarbon accumulation by affecting the distribution of hydrocarbon source rocks and reservoirs,The oil and gas in the target section of the study area are mainly distributed in the underwater distributary channel sand body.