利津洼陷沙四段烃源岩成烃特征及其对滩坝砂油藏的贡献

CHARACTERISTIC OF HYDROCARBON GENERATION OF SOURCE ROCK IN THE 4TH MEMBER OF SHAHEJIE FORMATION IN LIJIN SAG AND ITS CONTRIBUTION TO BENCH-BAR RESERVOIRS

对利津洼陷沙四纯上亚段和纯下亚段烃源岩地球化学特征的研究表明,两套烃源岩达到了好-较好烃源岩的标准,均可作为本区的有效烃源岩。从成烃特征来看,二者在伽玛蜡烷、三甲基萘、硫芴含量方面存在差异。油源对比表明,滩坝砂中原油饱和烃特征与纯上段烃源岩相似,芳烃特征更接近纯下段烃源岩,可见滩坝砂中原油主要来自纯上段烃源岩,也不排除纯下段的贡献。最后结合典型油藏剖面分析,建立了三种滩坝砂油藏成藏模式。

The studies of the geochemical characteristics of the source rocks in chunxia submember and chunxiasubmember of upper Es4 of Lijin Sag indicate that they are both high quality source rock and can be taken as ef-fective source rock in the area. The characteristics of hydrocarbon generation exist remarkable differences interms of the gammacerane,trimethylnaphthalenes and diben zothiophene content. Source correlation shows thatoils in bench-bar reservoirs were mainly sourced from source rock in chunxia submember of upper Es4,and thesource rock in chunxia submember of upper Es4 might also have play a certain role. Combined with the analysisof typical reservoir section,three reservoir-forming pattern of bench-bar reservoirs were established at last.