惠民凹陷阳信洼陷油气成藏条件及分布规律

通过构造环境、烃源岩演化史、储层特征及生储盖配置等方面分析,认为阳信洼陷成熟油气纵向上主要富集于沙四上、沙三层段,沙三段产低熟油,沙一段富集生物气,平面上油气主要富集于中部正向构造带,油气环绕次洼生烃中心呈环带状分布。油源条件、构造特征、火山活动以及生储盖组合与构造的配置等是控制阳信洼陷油气富集的主要因素。区域构造背景控制了油气运移的指向,油气源条件制约着油气的富集程度,生储盖组合与构造特征的配置,是造成不同构造部位主要储油气层位和油气藏类型差异性的直接原因。

Hydrocarbon accumulation conditions and distribution in Yangxin Subsag of Huimin Sag

The datum of tectonics background and thermal-history of hydrocarbon source rocks and reservoir attributes and source, reservoir and seal conditions are discussed and summarized. Yangxin subsag was many petroliferous zones vertically, and maturated oil-gas were generated mainly in upper Es4 and Es3, and low-matured oil-gas were produced mainly in Es3, and biogenic gas were fo＇rmed to Esl. Oil-gas were concentrated in central positive structural zones in plane, and were encircled to producing hydrocar- bon focus of inferior subsag according to circularity. The major factors controlling hydrocarbon accumula- tion include oil-source conditions, structural features, volcanic activities and the collocation of source rock-reservoir-caprock assemblages to structures. Territorial tectonic background controls hydrocarbon migration direction, and oil-source conditions constraints hydrocarbon enrichment, and the collocation of source rock-reservoir-caprock assemblages to structures is a direct reason for the differences of major hydrocarbon-bearing horizons and hydrocarbon reservoir types in different tectonic position.