金湖凹陷东部油源对比研究

Research on oil and source rock correlation in east Jinhu Depression

龚永杰 蒋有录 何胜

中国石油大学地球资源与信息学院，山东 东营 257061 胜利油田有限公司胜利采油厂，山东 东营 257051

金湖凹陷东部是苏北盆地最主要的油气产区，油气来源复杂，以原油和烃源岩饱和烃色谱、色谱-质谱分析为基础，将该区原油划分为来自阜四段烃源岩的“阜四型”和来自阜二段烃源岩的“阜二型”，其中“阜二型”占较大优势。综合地质背景和地球化学资料分析，认为该区油气主要来自■水、龙岗和三河3个次凹，其中“阜四型”原油主要分布在石港断裂带和龙岗次凹附近。“阜二型”原油在研究区广泛发育，按照甾烷异构体比值C2920S/（20S+20R）将阜二型原油进一步划分为未熟—低熟原油和低—中等成熟原油。研究表明，研究区原油遵循就近运移、聚集的基本规律，凹陷内各次凹中心即为油源中心。

As one of the most primary hydrocarbon habitats in Subei Basin, the east Jinhu Depression is charged by multiple source
rocks. According to the analysis of crude oil and rock’s saturated hydrocarbons chromatography and chromatogram-mass
spectrometry, the oil is divided into two types, E1f4 oil from E1f4 source rock and E1f2 oil from E1f2 source rock, and E1f2 oil takes the
dominant part. Based on the integrated analysis of geologic background and geochemical data, it is considered that petroleum in the
east Jinhu Depression mainly comes from Fanshui-Longgang and Sanhe Sub-depression. E1f4 oil is near Shigang faulted zone and
Longgang Sub-depression. E₁f₂ oil is broadly distributed. According to the ratio ofαααC₂₉20S/(20S+20R), E₁f₂ oil is divided into
immature to low mature oil and low to middle mature oil. The study shows that crude oil accumulates near the sub-depressions and
the center of oil sources is the center of sub-depressions.