Sedimentary Characteristics And Reservoir Study Of E_s~3 In Shuangtaizi Area,Western Depression,Liaohe Oilfield

Shuangtaizi area is located in the south of Western Depression and in the east of Qingshui Sag.The area of oil and gas in Es³ of oil and gas shows active,low degree of exploration,resources and great potential.But the stratigraphic conditions complex,sedimentary facies and effective reservoir distribution and controlling factors of unclear problem has restricted the deep exploration.Through multiple data,the three key problems of restricting the exploration-sequence stratigraphy,sedimentary,reservoir are researched deeply.Characteristics and controlling factors of sedimentary facies and reservoir characteristics,and point out the exploration direction,the main research achievements are as follows and understanding:On the basis of previous studies in Es3 is divided into 4 fourth order sequences.Further SQ₂²?SQ₂³ and SQ₂⁴ divided into 6 sand group;the are SQ₂²-??SQ₂²-??SQ₂³-??SQ₂³-??SQ₂⁴-?and SQ₂⁴-?.According to the drilled wells the oil and gas,SQ₂⁴-??SQ₂³-?and SQ₂²-?sand group is the first choice to exploration.The sedimentary system of sublacustrine fan is mainly developed in Es3.The sand body distributes fan-shaped along the synsedimentary fault zone;The gravity flow types are subdivided,and the sedimentary model of gravity flow in the Shuangtai tectonic belt is established.The northern part is in the sliding-collapse stage of gravity flow evolution,and the south part is in the clastic flow stage.In the study area,reservoir composition and structure maturity are low.The pore types are intergranular dissolved pore,intragranular dissolved pore and micropore,.According to the physical properties,the reservoirs are divided into three categories.Sedimentary and diagenesis are two main factors to control reservoir quality.The dominant reservoirs are mainly distributed in medium-coarse sandstone with buried depth.The dominant reservoirs in the secondary pore developed section are widely distributed.On the basis of reservoir prediction and evaluation,the exploration of lithologic oil-gas reservoir is highlighted,and two favorable exploration targets are selected through objective evaluation.