含油气盆地流体流域系统及其油气聚集原理

Fluid drainage system of petroliferous basins and its hydrocarbon accumulation principle

在含油气盆地形成和演化过程中,先后有两个孕育和养护油气生成、运移和聚集为矿藏的流体流域系统,即水流域系统和油气流域系统。水流域系统的形成和发育建造了包含烃源岩、输导层、区域盖层和圈闭体等成藏要素在内的沉积体系,是谓母体系统。烃源岩在母体系统中形成,经由埋藏生成油气,然后油气又返回母体,以其中的成藏要素格架为载体,逆倾向而上形成自己的流域系统,最后在所遇圈闭体中聚集成藏,是谓子体系统。母体系统建造的沉积体系为子体系统创建和提供了一切必要的成烃、成藏条件和环境。子体系统以母体系统为依托,在其体内完成了成烃、成藏过程。二者先后有序地发育和其中各种作用的形成及有机匹配,是自然界造就的一个天然程序。从而,根据此程序建立与之相适应的含油气盆地油气聚集原理。

There were two fluid drainage systems in the generation and evolution of the petroliferous basins, including the water drainage system and hydrocarbon drainage system. The two fluid drainage systems gave birth to and bring up hydrocarbon genera tion, migration and accumulation to generate oil and gas pools. The water drainage system is the parent one, and the hydrocarbon drainage system is the descendant one. The generation and development of the water drainage system built up the depositional system containing various key factors for forming pools, such as source rock, carrier bed, regional cap rock and trap. Source rocks formed in the parent system and transformed into hydrocarbon under burial condition,and then the hydrocarbon went back to the parent sys tem. Taking the framework of pool-forming factors as carrier, the hydrocarbon formed the descendant system in the up-dip diree tion. Finally, hydrocarbon formed pools in the met traps. The depositional system built by the parent system created and supplied all necessary conditions and environments for the descendant system, that was supported by the parent one and finished the hydrocar bon-forming and pool forming processes within the parent system. The two systems were developed in order and formed a natural procedure, in which various functions could take place and match each other in a favorable way. Therefore, a hydrocarbon accumulation principle, which is suitable to and based on the procedure,is established.