储存域与油气成藏的有效性分析

Analysis on the oil storing area and validity of hydrocarbon reservoir forming

油气勘探实践证实,不同深度含油层段的原油性质存在明显的差异;有时同一套含油气系统的同一个流动单元,深、浅部位的原油性质也存在差异。据此发现油气聚集后得以有效保存不仅需要储集条件,还需要一个维持油气性质稳定的空间域,定义为储存域。根据济阳坳陷油区的资料,对储存域进行了储层矿物学和元素地球化学参数的界定。阐述了储存域与油气生成和排聚的关系。提出了分析油气成藏有效性的甄别方法,即落实储存域与油气生、储、盖组合配置的关系,从动态构造演化过程中寻找油气聚集与储存域的吻合性。

Oil and gas exploration practice proved that there is great difference among the crude oil characters in different oil-bearing formations at each depth. Sometimes the character of crude oil in deep position is very different from shallow position in the same flow unit in a same petroliferous system. According to this, it is found that there needs an area of space for effective conservation which kept the hydrocarbon character stabilization except for the reservoir condition after oil and gas accumulated. The area is called ' oil storing area'. Through utilizing the information of Jiyang Depression, the oil storing area is determined with some parameters in reservoir mineralogy and element geochemistry. The relation between the oil storing area and hydrocarbon generating and accumulating is expounded. A method that analyzes the validity of hydrocarbon accumulating has been brought forward. That is to distinguish the relationship between the oil storing area and hydrocarbon source-reservoir-seal assemblage. The matching rate of oil-gas accumulation and the oil storing area must be found from dynamic structure evolution process.