Hydrocarbon Distribution Features And Accumulation In Permian Of Ke-Bai Area

Ke-Bai area is seated Ke-Bai fault belt of western uplift in Junggar Basin. West tied with hill, East Junggar basin body Mahu sag, south of Hongche fault belt, north of wuxia fault belt. The study area, including five, eight district and Baikouquan area. The Permian of Ke-Bai area has great exploration potential, and the80%remaining reserves exist in exploration difficult lithologic and stratigraphic trap in ramp region of foreland basin. Therefore, the area of oil and gas exploration work is very important. Research on oil and gas reservoir formation is mainly an analysis of oil and gas reservoir characteristics, formation and distribution of oil&gas, is one of the important content of petroleum geology theory. In this study, designed to fully absorbing the previous research on the basis of analysis of oil and gas distribution features and migration features, summarized oil and gas reservoir forming rules,.The master’s thesis, is based on systematic collection of logging, oil test, logging and oil geochemical data, and relevant research area of sedimentary tectonics and evaluation of hydrocarbon source rocks, systematic analysis the Permian layers of Ke-Bai area respectively typical hydrocarbon reservoir characteristics, oil and gas distribution and migration of oil and gas law; and combined with the basis of the above research, comprehensive analysis of oil and gas accumulation model and summed up the oil and gas accumulation.Work area was common controled by Karamay fracture, Baijiantan fracture, and Baikouquan fracture, the overall performance for the tilt to southeast slope, slope internal only developed some small faults. Bottom-up development of Jiamuhe group, Fengcheng group, Xiazijie group, lower Wuerhe formation and upper Wuerhe group. Mainly in the alluvial fan facies, fan delta facies, in Jiamuhe Formation and Fengcheng group also development of volcano sedimentary facies. Combined with regional geology data and based on logging、oil testing and reservoir date that we can conclude:Fifth regional reservoirs are common developed both in slope and fault zone。Reservoirs of Wu Erhe formation are main existing in south and east of fifth region, while fault-strata reservoirs are developing in Ke75and Fifth3area which controlled by faults; Ke79and Ke82controlled by lithology have lithologic reservoirs; And there are many volcanic reservoirs developing under the unconformity of Feng Cheng formation in Ke80area. Fault-lithologic reservoirs are well developed in fault zone of Feng Cheng、Xia Zijie and Xia Wuerhe formation in Eighth area controlled by faults and fans, and for the same controlling factors, fault-lithologic reservoirs are well developed in fault zone ofJia Muhe、Xia Zijie and Xia Wuerhe formation in Bai Kouquan area.Based on the logging and oil production testing data analysis, Combined with structural and sedimentary characteristics, the Permian oil-gas distribution characteristics were summarized. Permian oil-gas mainly distribute in Jiamuhe formation and upper Wuerhe formation, especially gas reservoir distribution only in the two layer, and oil and gas along the surface of unconformity distribution; lower Wuerhe formation and Xiazijie integrated contact, a plurality of fan body overlap in vertical and horizontal, oil and gas are distributed in each section; Fengcheng group mainly distributed in the upper part. Planar oil-gas mainly distribute along the formation pointed out line and fault, and oil testing and logging interpretation results for oil or oil and water in same layer. to the center of the depression, the oil-gas gradually reduce, and oil test and the results of well log interpretation for oil layer.Conbinated with geochemical data about source rocks and crude oil and foundamental geological information,the author analyzed oil and gas sources and the principle of hydrocabon migration.The result of analyzing show that the A1and A2type of crude oil derived from Fengcheng Formation source rocks,and the B type of oil,mixed with oil of deriving from the lower Wuerhe Formation;the deravation of sapropelic gas was the Fengcheng Formation source rock,while the humic type natural gas derive from Jiamuhe Formation. As a whole,there was a trend of the migration of oil and gas from the low point of structrue to the higher,and the pathway of oil and gas migration mainly is the fault and the unconformity.Taken together, the hydrocarhon reservoirs of the Permian is controlled by unconformity.faults.the distribution of facies and seal.Firstly,the unconformity,faults and rock prevent the migration of oil and gas.Secondly,the unconformity,faults and sands can be regarded as the conduit of oil and gas.Thirdly,sands and igneous can be the reservoirs.Well,there along the unconformity and faults exists favorable reservoirs.As a result,oil and gas accumulate alone the unconformity and faults.Since the respective factors play its own role in the accumulation of oil and gas,the hydrocarhon reservoirs in disternct layers have their own characteristics.