中文摘要：

采用饱和压力法确定油藏成藏期的原理和方法一直存在争议,在高勘探程度区济阳坳陷的应用中发现,该方法对许多油藏不适用,所推测的成藏深度和成藏期与实际情况相差较大。以济阳坳陷众多油藏资料为基础,结合坳陷油气生成、运移过程中原油的饱和压力变化特点,就该方法对许多油藏不适用的主要原因进行了分析：济阳坳陷地下原油黏度影响因素较多,总体上与其是否为天然气所饱和关系不大;济阳坳陷古近系烃源岩生成并排出的大部分原油为欠饱和原油,大部分原油在欠饱和状态下运聚成藏是该方法对许多油藏不适用的主要原因,饱和压力法仅适用于原油在饱和状态下聚集成藏的油藏。据此认为：原油既可以在饱和状态下大规模聚集成藏,又可以在非饱和状态下大规模聚集成藏,因此,运用饱和压力法确定成藏时期前,首先要明确该油藏中的原油是在饱和条件下聚集成藏的。

英文摘要：

There have been arguments on the principle and method of oil saturation pressure for determining the accumulation period of oil reservoirs.The application of the method in the high-exploration-degree depression,Jiyang Depression,shows that the method is not fit for many reservoirs,the inferred depths and periods of the oil accumulation do not match the actual conditions.Based on the study of the oil saturation pressures in the reservoirs and the change of the oil saturation pressures in the oil generation and migration stage,this paper analyzes the reason why the method is not working for many reservoirs in the Jiyang Depression.In the Jiyang Depression,the saturated oils are not necessarily lowest in viscosities and easiest to migrate in formation conditions.Most oils generated and expelled from the Paleogene source rocks of the Jiyang Depression are unsaturated.The oils migrating and accumulating in an unsaturated state are the main reason why the oil saturation pressure method does not work in the area.Oils can accumulate in a large scale both in a saturation state and in an unsaturated state.So,the saturation pressure method cannot be used to determine the accumulation period of a reservoir before it is clear that the oils in the reservoir were accumulated in a saturated state.