| Yitong basin is located in the eastern part of jilin province, It's the Strick-slip Fault basin of Tertiary in Jilin province, which belong to the southern part of Jiamusi-Yitong graben, also it's the North-extension of the Tanlu fracture and running across Changchun and Jilin along north-west direction, the area is about 2200 square kilometers. It's divided into Moliqing fault depression,Luxiang fault depression,Chaluhe fault depression, It auxesis Shuangyang formation,Sheling formation,Yongji formation,Wanchang formation,Qijia formation of Paleogene, Chaluhe formation of Neogene and Quaternary in the basin. By the study of sedimentary facies analysis of source rock series, Characteristics of reservoir, the text definitudes the major zones'oil and gas source and migration direction Liangjia structure belt, In addition, discussed the model for formation of reservoir of fault basin.Liangjia structure belt is very complicated in shallow layer, There is no typical mark layer. In view of the content of the researchin this project, In order to resume the paleo-sedimentary characteristic of the first and second of Wanchang formation and the bottle of Qijia formation, On the basis of using drilling stratified data partly by predecessor, By using of the correction of logging cure and calibration of synthetic seismogram, we carry on the stratigraphic correlation of stratified boundary of every members of Wanchang formation and the first member of Qijia formation and set up the stratigraphic framework of this area.In this research, by the detailed observation of rock core and the analysis of logging and seismic data, Combing with some methods such as rock and mineral identification and grain analysis,We identificated two sedimentary facies from Wanchang formation strata in the research area.They are lacustrine face and shallow nearshore subaqueous face. Further, they are allocated into 6 sedimentary subfacies and 10 sedimentary microfacies.In the whole sediment form the first member of Wanchang formation to the third member of Wanchang formation, Southeast accommodation which come from the chang 30 to chang 105 well zone is alwaysly stable material source and chang less,. Southwest accommodation which come from xing 6 to xing 108 have been decreasing. The two accommodation which come from chang 29-1,xing 19 and xing 19-3 aren't stable in the sedimentary process and swing intensively after entering lacustrine basin. It make the sedimentary facies chang obviously in different stage.By analysis of the date of porosity and permeability in the research area, We recognize that the reservoir petrophysical property is the best favorable with medium and low porosity and medium anf low permeability. On the basis of analyzing the data of the reservoir porosity and permeability, because of compaction , The porosity and permeability decrease along with the increase of the depth in the whole, but the dissolution make secondary porosity more big. In 750m～1500m, there is the first secondary porosity. There are second secondary porosity in more deep section. In research area, the influential factors of reservoir property is depth,grain,separation the type of sedimentary microfacies,diagenesis and so on. In the stage of Shuangyang formation,Sheling formation and Yongji formation, the sedimentary face of the study area is mainly half deep lake—deep lake. There are mainly three sets of source rock which distribute broadly and deposit thickly, It makes the solidly foudmation for hydrocarbon generating. In Wanchang formation and Qijia formation the exogenous sub-lacustrine fan sand body upgrowthed in the lake, which proviod a favorable reservoir space for the hydrocarbon accumulation and form good reservoir-seal combination.Through the analysis of the typical oil and gas reservoir which have been found in the study area. Combining the analysis of the regulation of Hydrocarbon accumulation, According to trap shape and genetic types,we consider that the types of oil reservoir which may exist are fault-anticline oil and gas reservoir,Step-fault reservoir,Uplift in the graben oil and gas reservoir,Lens of lithologic reservoir,fault-lithologic pinch out on the dump reservoir, On the basis of the research of oil and gas geological conditions, Combining with a comprehensive analysis of the characteristics of reservoir profile, We summarize preliminary the regulation of hydrocarbon accumulation and set up its basic mode. Hydrocarbon accumulation in this area include mainly the following Aspects:①Adequate oil and gas sources are the basis for hydrocarbon accumulation;②Good oil and gas migration pathway is a necessary condition for hydrocarbon accumulation in the Oligocene;③A certain amount of storage space and matching of Reasonable reservoir-seal combination is assurance of hydrocarbon accumulation.The mode of hydrocarbon accumulation in this area are as follows: Hydrocarbon source rocks in Shuangyang Formation enter the stage of low-mature in early Yongji Formation, Low mature oil and gas was generated mainly in Yongji Formation. Apart from some of the supply for its own reservoir, the rest of oil and gas escape along the edge of fault-controlled basin. Hydrocarbon source rocks in shuangyang Formation generate mainly mature oil in the deposition stage of wanchang Formation, Hydrocarbon source rocks in sheling formation generate mainly low mature oil and gas, major oil source is from the hydrocarbon source rocks in shuangyang Formation. At that moment,Ⅱfault activities strongly, Not only some rolling anticline were formed in Wanchang Formation of liangjia structure zone, But also a series of fault of internal basin were developed, which were in the same or opposite direction with fault-controlled basin in the edge of basin, In spite of disconnected distance of these fault, they established the relationship between hydrocarbon source rocks and reservoir in lower part with the reservoir in Wanchang and Qijia Formation in upper part, which make some part of mature medium oil and moisture migrated upward along theⅡfault and gather in the upper reservoir.
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