西非加蓬海岸盆地盐岩特征及其石油地质意义

Characteristics of salt of Gabon coastal basin in West Africa:implications for petroleum exploration

刘深艳 胡孝林 常迈

LIU Shenyan HU Xiaolin CHANG Mai

中海油研究总院海外评价中心, 北京 100027

Overseas Assessment Center, CNOOC Research Institute, Beijin 100027, China

加蓬海岸盆地主要分为南加蓬次盆和北加蓬次盆,是典型的西非被动大陆边缘含盐盆地,盐岩的分布具有一定规律性和差异性,并且对盆地内油气成藏具有重要的控制作用。分析了加蓬海岸盆地的构造演化与沉积充填特征、基本石油地质条件、盐岩的分布特征及其对盆地烃源岩特征、储层分布、圈闭特征、封盖条件、油气成藏,以及油气藏储量等各方面的影响与控制作用,并指出,由于加蓬海岸盆地的绝大多数油气成藏都与盐岩密不可分,因此深化盆地内盐岩展布特征的研究,对进一步评价北加蓬次盆的盐下层系及南次盆登泰尔地堑的勘探潜力具有重要意义。

Gabon Coastal Basin can be mainly divided into South Gabon Sub-basin and North Gabon Sub-basin, and it is a typical west African passive margin salt basin. Its salt distribution shows some patterns and differences, and it is a controlling factor of the reservoir formation in the basin. This paper analyses the geological aspects of Gabon Coastal Basin as follows:tectonic evolution, sedimentary filling, basic geological conditions and salt distribution, and studies their controlling effects on source rock, reservoir distribution, trap, sealing and reservoir formation. In conclusion, this paper points out that it is important to further research the salt distribution in the basin as the formation of most reservoirs in Gabon Coastal Basin is closely correlated with the salt, and it is of great significance for the evaluation of exploration potential of Subsalt Strata in North Gabon Sub-basin and Dentale Trough in South Gabon Sub-basin.

https://doi.org/10.3969/j.issn.1008-2336.2011.03.001