马朗凹陷哈尔加乌组烃源岩分布和生烃演化与石炭系成藏关系

通过井震结合烃源岩预测技术、盆地模拟技术和油源对比、原油运移示踪技术,对马朗凹陷石炭系火山岩系哈尔加乌组烃源岩分布与烃源岩(灶)生烃演化规律、石炭系原油和烃源岩地球化学特征及原油运移特征等方面进行研究。结果表明:马朗凹陷石炭系火山岩系烃源岩主要有正常沉积型和火山碎屑沉积型两种赋存型式,烃源岩与火山岩具有4类共生关系;马中构造带石炭系原油为高成熟度原油,牛东构造带石炭系原油主要为成熟油;牛东构造带石炭系原油主要为马朗凹陷北斜坡带牛东本地成熟烃源岩所生,于白垩纪中晚期开始大量生烃,自东向西运移成藏;马中构造带油气来自凹陷中心高成熟烃源岩。

Relationship between distribution, hydrocarbon generation and evolution of source rock in Haerjiawu formation and Carboniferous hydrocarbon accumulation in Malang sag, Santanghu Basin

By using a series of techniques such as logging-seismic source rock prediction, basin simulation, oil and source rock correlation, and crude oil migration tracing, the distribution and hydrocarbon generation evolution of Haerjiawu formation source rock, geochemical features of Carboniferous crude oil and source rock, and the migration patterns of crude oil in Malang sag were studied. The results show that the source rock of Carboniferous oil in Malang sag mainly has two types of occurrence patterns, namely normal sedimentation and sedimentation of clastic rocks. There are four symbiotic relationships between source rock and volcanic rock. The Carboniferous crude oil in Mazhong tectonic belt is of high maturity, while that of Niudong tectonic belt is mature. The Carboniferous crude oil of Niudong tectonic belt is mainly generated by the local mature source rock in the northern slope of Malang sag, and large-scale hydrocarbon generation started during the middle-late Cretaceous and migrated from east to west. The oil and gas of Mazhong tectonic belt is generated by the high mature source rock in the center of the sag.