Petroleum accumulation factors of Qigu formation of Jurassic in the Fudong slope, Junggar basin

Abstract：In order to clearly understand the petroleum accumulation factors of Qigu formation in the Fudong slope area of the Junggar basin and to provide reliable guarantees for oil and gas exploration and development of Xinjiang Oilfield Company, macroscopic data such as drilling wells and earthquakes, and microdata such as thin sheets, X diffraction and scanning electron microscopy were used to analyze the petroleum accumulation conditions (hydrocarbon source rock characteristics, reservoir characteristics, dredging system characteristics and abnormal pressure characteristics) in Qigu formation.Conclusions were drawn as follows: (1) The oil sources of the Qigu formation reservoirs included the Permian and Jurassic hydrocarbon source rocks, mainly Jurassic. (2) Reservoir sands in first member of Qigu formation were mainly underwater distributary channel sands, and in second and third member of Qigu formation, were mainly distributary channel sands.Sedimentary environment, abnormal pressure and volume fraction of tuffaceous component were controlling factors of high quality reservoir sands. (3) The Qigu formation hydrocarbon dredging grid were composed of conncted oil source fracture and dredging layer. (4) The Qigu formation mainly developed tectonic-lithologic reservoirs and locally developed lithologic reservoirs, which had great exploration potential.

Keyword：petroleum accumulation rule;petroleum exploration;Jurassic Qigu formation;Fudong slope area;Junggar Basin;