Fuxin Basin is a graben-type basin that covers an area of 2000 km

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formed on Pre-cambrian basement during Late Jurassic-Early Cretaceous.Contemporaneous faults could be primarily classified into two groups such as NNE-stretching and NW-stretching faults.The former controlled the thickness and distribution of Upper Jurassic

and the later con-trolled the distribution of coal-rich zones and local structures.The Jiufotang Formation and the third-fourth member of the Shahai Formation are the main source rocks whose organic matter is mainly type-Ⅱ

and the threshold depth of oil-generation that is calcu-lated with average 3.93℃/100m of geothermal gradient is 1350 m.Reservoirs occupy 70% of the total sediment thickness

in which sandbodies of fan-delta and subaqueus gravity-flows are more favourable for hydrocarbon preservation.