断陷盆地烃类流体运动的非均一性

The heterogeneity of hydrocarbon fluid movement in faulted basin

为研究断陷盆地中烃类流体的运动特征,对断陷盆地中烃源岩的分布、排烃过程及油气二次运移通道及过程进行了分析。结果表明,断陷盆地中烃源岩的分布存在强烈的非均一性,宏观上烃源岩的分布呈现旋回式,微观上烃源岩分布具有一定的波动性。非均一性是烃类运移的本质特征,烃类运移存在优先的运移方向、通道及目标。流体压裂是驱动超压封存箱幕式演化的重要方式,随着超压封存箱的幕式演化,烃类进行幕式排放、幕式运移及幕式成藏。在烃源岩体系中讨论不同规模盆地内油气的运移规律时,应该充分考虑到油气运移通道的不连通性,重视突变性的油气运移规律。

In order to investigate the characteristics of hydrocarbon fluid movement in faulted basin,the distribution of source rocks,the hydrocarbon generation and expulsion,and the secondary migration process in the faulted basin were analyzed in this paper.The results show that the distribution of the source rocks in the faulted basin has strong heterogeneities.The macroscopic characteristics are cyclic sedimentation and the microscopic heterogeneities behave as fluctuation of the distribution of organic matter in the source rocks.Heterogeneity is the essential characteristic of hydrocarbon migration,and there are preferential directions,pathways and target in the course of it.Hydro-crack is an important means to drive episodic evolvement of over-pressured compartment.The episodic evolvement is a unitive and continuous course for hydrocarbon expulsion,migration and accumulation.When hydrocarbon migration laws in basins in various scales were discussed,the non-connectivity of hydrocarbon migration pathways should be taken into consideration and the abrupt hydrocarbon migration should be stressed.