珠江口盆地珠一坳陷惠陆油区含油气系统与油气运聚成藏模式

The Petroleum System and Hydrocarbon Migration and Accumulation Mode of Huilu Oil Region in Zhu 1 Depression of Pearl River Mouth Basin

珠江口盆地珠一坳陷惠陆油区具有3个经油气勘探证实的含油气系统,分别是惠西、惠东、惠中北含油气系统。惠西与惠东含油气系统烃源岩为始新统文昌组中深湖相;而惠中北含油气系统烃源岩为下渐新统恩平组煤系。惠陆油区油气运聚成藏模式存在2种类型即:古近系半地堑洼陷自源型油气运聚成藏模式与三角洲砂岩及生物礁外源型油气运聚成藏模式。前者油气运聚成藏的主控因素,主要取决于半地堑洼陷内生烃灶充足的烃源供给、优质储盖组合及圈闭的良好配置。这种油气藏分布于半地堑洼陷之内,具有自生自储近源运聚成藏特征,由于此类油藏埋深较深,深部储层物性优劣是油气成藏的关键;后者油气运聚成藏主控因素,则主要取决于富生烃洼陷及其附近的油源断裂和输导砂体及不整合面组成的复合运聚疏导体系与浅层不同类型有效圈闭的连通配置和相互衔接耦合。

There are three petroleum systems confirmed by oil and gas exploration in the Huilu oil region of Zhu 1 Depression,namely Hui West, Hui East, Hui Middle-North petroleum system. The source rocks of Hui West and Hui East petroleum systems are Wenchang Group in Eocene with middle-deep lake facies deposition,while source rocks of Hui Middle-North petroleum system are Enping Group in I.ower Oligo- cene with coal. Namely there are two types of oil and gas migration and accumulation pattern：hydrocarbon accumulation mechanism of the source from half-graben-type depressions in Paleogene, hydrocarbon accu- mulation mechanism of delta sands-reef exogenous. Controlling factors of hydrocarbon migration and accumulation mainly depend on good configuration of adequate supply of hydrocarbon source, high quality res- ervoir-seal assemblage and traps. Such reservoirs within the half-graben possess self-generating and self storage characteristics, because such reservoirs are buried deeply, reservoir properties are the key control- ling factor on hydrocarbon accumulation. The latter controlling factors of hydrocarbon migration and accu- mulation mainly depend on good configuration of the shallow structure and hydrocarbon source fault sys- tem and the sand ridges.