| Yitong basin is located in the eastern part of Jilin province,It's the Strike slip Fault Basins of Tertiary in Jilin province.,which belong to the sothern 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 auxesis Shuangyang formation,Sheling formation,Yongji formation Wanchang formation Qijia formation of Paleogene,Chaluhe formation of Neogene and Quaternary in the basin. Chang30 well area is located in the southern part of Chaluhe fault depression of Yitong basin. in the well area,Iiangjia structure selt is located in the downthrown side of the No.2 fault ,it's the directed area of oil,gas migration because in the northwest it adjacent to Xin'anbao source sag.By the study of sedimentary facies analysis of source rock series, Characteristics of hydrocarbon source rock and geochemical characteristics of crude oil,the text definitudes the major zones' oil and gas source and migration direction of Liangjia structure selt, Inaddition, discussed the model for formation of reservoir of faulted basin.By the In-depth study of rock core, Logging and Seismic Data,we identificated two sedimentary facis from Shuangyang formation strata to Wanchang formation strata in the the research area,they are lacustrine facies and exogenous Sub-lacustrine Fan facis, further,they are allocated into 6 sedimentary subfacies and 13 sedimentary microfacies. In the third member of Shuangyang formation,the sedimentary face of the study area is exogenous sub-lacustrine fan -half deep lake which constituted by northwest,southeast,east accommodation with the Xin'anbao depression as sedimentary center as a whole. In the first member of Sheling formation and the second member of Yongji formation,the material sources are mainly from southeast and east, the northwest material source disappeared. In the third and forth member of Yongji formation, the water body deepen, the northwest material source still undeveloped,the sedimentary face of the study area is exogenous sub-lacustrine fan -half deep lake -deep lake. In the Wanchang formation, the water body shoaled, the exogenous sub-lacustrine fan upgrowthed,especially the northwest exogenous sub-lacustrine fan of whose extension range get across centra of the fault depression even connect as one with southeast exogenous sub-lacustrine fan, the sedimentary face of the study area is exogenous sub-lacustrine fan -akeshore or mere sedimentary system.This research on the basis of using the existing test analysis,also fully utilizes the test analysis predecessor did in the study area.By analysing the organic matter abundance, type of organic matter and maturity of organic matter of the dark mudstone, binding the development characteristic of the dark mudstone,the text analyses the hydrocarbon generating condition of the dark mudstone of Shuangyang formation,Sheling formation and Yongji formation in the study area.The dark mudstone of the first member of Shuangyang formation and the first member of Sheling formation are belonged to good source rock. The dark mudstone of the second and third member of Shuangyang formation, the second and third member of Yongji formation are belonged to preferable source rock.The dark mudstone of the fourth member of Yongji formation is belonged to discrepancy source rock.Of whice the source rock of the first member of Shuangyang formation begins entering into low mature stage in the early Yongji formation, it entered into mature stage in the Wanchang formation and entered into high mature stage in Qijia formation and neogene,it's the main mother rock of the mature oil of the study area,also it's the main mother rock of the gas of the study area. The source rock of the second and third member of Shuangyang and the first member of Sheling enters into mature stage at present,but some of the dark mudstone of Yongji formation is belonged to mature source rock,some belonged to low mature source rock.Syntheses the oil gas distribution of all well in the study area,at present,the main hydrocarbon-bearing formation distributes in the first member of Sheling formation,the second member of Yongji formation and the first and second member of Wanchang formation.By adopting group composition,satisfied hydrocarbon gas chromatogram characteristic, aromatic hydrocarbon gas chromatogram characteristic,carbon stable isotope etal organic geochemistry attribute, i analysed the the origin of the oil and gas of the main stratum of the study area.The result shows that,the crude oil of the first member of the Sheling formation possibly have mixed sources,not only supplied by the source rock of Shuangyang formation,but also the source rock of the first member of Sheling formation. The crude oil of the second member of the Yongji formation is come from the underlain source rock of Shuangyang and Sheling formation.The mother rock of the natural gas of the first and second member of Wanchang formation mostly are the source roce of Shuangyang formation. When the oil and gas of the deep Shuangyang formation and Sheling formation produced,not only accumulated in the edge of sublacustrine fan sand bodies of deep stratum, fromed lobate lithologic trap in the midfan of the underwater fan whose inner fan were either subaqueous debris flow or olistostrome,but also under the communication of the cocurrent or antithetic fault in the basin,oil and gas migrate upward along faults,when they meet the rolling anticline trap which formed by the sublacustrine fan sand bodies of the upper Sheling formation,Yongji formation and Wanchang formation,they accumulated and formed typical rolling anticline oil - gas reservoir.
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