反转构造进展与油气聚集关系

Review of Inversion Structure and the Relationship Between Hydrocarbon Accumulation and Inversion Structure

反转构造主要指伸展盆地中地堑、半地堑系统遭受挤压变形所产生的压缩构造。它一般经历拉张断陷、稳定坳陷及挤压反转3个演化阶段,构造反转形成的各种褶皱背斜构造直接叠覆在生油断陷之上,生运储配置关系得天独厚,其复杂性及重要性值得深入研究。通过对与反转构造相关的大量文献的调研及对中非B走滑拉分盆地反转构造样式的研究,对反转构造概念的演变、类型的划分、识别、反转率的计算等方面研究进行了全面归纳和总结,并提出了反转构造研究中存在的问题。研究表明,反转构造类型的划分主要是以断层和褶皱对反转构造的影响和控制作为依据;鉴别反转构造应在区域构造事件、上下构造层褶皱变形特征、断层性质及活动历史等多方面分析基础上进行;利用挤压反转后的断裂和褶皱变形特征可以定性描述构造反转程度,划分为轻微反转、中等反转、强烈反转等,而反转率的计算能够比较好地定量描述反转的程度。

Inversion structure is a kind of compressional structure formed through the extrusion of the graben or half-graben system in the extensional basin.Extensional subsidence,stable depression and extrusion inversion are three stages generally going through in the inversion structure.The faults connected with the source rocks are overlaid by various anticlines caused by the tectonic inversion,with a very interesting relationship among transportation,generation and reservation.The inversion structures were extensively studies.This paper focuses on the inversion structure styles of strike-slip B basin in African,including the concept evolution of inversion tectonics,the types of inversion tectonics,the identification of inversion tectonics,and the inversion rate.Several existing problems of the inversion structure are discussed.It is shown that,the styles of the inversion structure are mainly classified based on the influence and the control of the faults and fold structures.The tectonic inversion should be identified based not only on the analysis of the regional event,but also on the features of folds and faults and the activity history.The degree of the tectonic inversion can be described qualitatively and divided into three levels：the slight inversion,the moderate inversion and the strong inversion based on the deformation characteristics of the reverse faults and folds.The inversion rate can be calculated to quantify the degree of inversion accurately.