前陆盆地结构单元与油气成藏响应

在成藏研究中，前陆盆地可以划分为前陆褶皱冲断带、前渊坳陷带、斜坡带和前缘隆起带等4个结构单元。为揭示盆地油气分布规律和不同结构单元之间油气聚集的差异性，通过对烃源岩、储集岩、生储盖组合和油气运移等主要成藏要素的分析，从前陆盆地系统各结构单元讨论油气分布规律和成藏模式，认为前陆盆地的油气分布受控于盆地结构、油气成藏与盆地结构单元相响应。在前陆盆地系统结构单元正确划分的基础之上，综合分析不同结构单元成盆期前和成盆期沉积体系的成藏特征，是前陆盆地油气成藏研究的重要发展方向，而对于中国中西部前陆盆地的油气勘探还必须重点考虑后期改造作用。

Response of Structural Elements to Hydrocarbon Accumulation in Foreland Basin

A foreland basin system may be divided into four structural elements such as piedmont fold-thrust belt, foredeep depression belt, slope belt and frontal uplift belt. This paper discusses hydrocarbon distribution regularity and hydrocarbon accumulation pattern of each structural element in foreland basin system by analysis of key factors of source rock, reservoir rock, source-reservoir-eaprock assemblage and petroleum migration in order to post the differences of hydrocarbon accumulation among different structural elements and basinal petroleum distribution regularities. The study shows that the petroleum distribution in foreland basin is controlled by the basinal structure, and a hydrocarbon accumulation is responsible to the basinal structural element. Based on this proper classification, to comprehensively understand the hydrocarbon accumulation characteristics of sedimentary systems of pre-basin-forming and basin-forming period for different structural elements is the crucial way for foreland basin hydrocarbon accumulation study. Moreover, the postreformations must be paid more attention to for petroleum exploration of foreland basins in central-western China.