松辽盆地长10地区为典型凹陷斜坡区有效烃源岩外成藏。通过岩心、测井和地震等资料对扶余油层油气来源、砂体展布、构造特征和油水分布等成藏因素的分析认为：油均来自三肇凹陷向斜区的青一段源岩；T2断层具有平面条带状特征，成藏期活动的油源断层多为密集带边界断层；扶余油层为西南保康物源影响下的河控三角洲，微相类型主要为分流河道，且垂向上发育先水退、后水进的沉积序列；油垂向分布在扶余油层顶部，受凹陷源外斜坡区供油不足的影响，油自构造低部位向高部位呈“台阶状”分布。扶余油层成藏模式为三肇凹陷青一段源岩生成的油在超压作用下通过油源断层向扶余油层“倒灌”运移．然后在浮力作用下，沿着水退最大期（扶Ⅰ组底）发育的河道砂体匹配油源断层组成优势输导通道（断层密集带），远距离侧向运移，因此斜坡区油在平面上富集于断层密集带附近，垂向上位于优势输导层位之上（扶Ⅰ组）。%Chang 10 area is of the typical accumulation outside effective hydrocarbon source on slope of depression. The cores, well loggings and seismic data were used to analyze the main controlling factors such as oil origin, sand body distribution, structural features and oil and water distribution. The result shows that oil was generated from syncline source rocks of the first member of Qingshankou Formation in Sanzhao Sag; T2 fault concentrates into belts in plane, and oil sources faults that was active accumulation are border faults around concentrated belts; Fuyu oil layer developed river-dominated delta under Baokang source from southwest, and microfacies were mainly distributary channels with a sedimentary evolution of reliction to transgression overlaying in vertical; oil was distributed on the top of Fuyu oil layer in vertical, and decreased from structurally low position to high position, distributing in step shape, under the effect of insufficient supply on the slope. Accumulation mode is that oil which was generated from source rock in the first member of Qingshankou Formation first downward migrated to Fuyu oil layer through oil-source faults under the action of overpressure, then laterally migrated through preferential migration pathways formed by matching between channel sand developed during the largest retrogradation （bottom of Fu Ⅰ ） and oil faults under the action of buoyancy,and oil accumulated in fault-concentrated belts in plane while distributed in upper preferential transforming layers in the vertical.
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