下刚果-刚果扇盆地沉积-构造演化与油气勘探领域  

Sedimento-tectonic Evolution and Petroleum Exploration Domains of Lower Congo-Congo Fan Basin

作　　者：孙自明[1] 

机构地区：[1]中国石化石油勘探开发研究院,北京100083

出　　处：《现代地质》2016年第6期1303-1310,共8页Geoscience

摘　　要：下刚果-刚果扇盆地位于西非海岸,因其富含油气,资源潜力大,长期以来一直引起众多研究者的关注。由于该区盐构造发育,变形复杂,盆地不同地区和不同勘探目的层勘探程度并不均衡,如何全面认识和评价盆地油气资源潜力成为指导下步勘探工作的关键。通过盆地沉积-构造演化特征研究,指出下刚果-刚果扇盆地是由下刚果盆地与刚果扇盆地垂向上叠置、平面上复合所形成的叠合复合型含油气盆地,经历了前裂谷期、陆内裂谷期、陆间裂谷期和被动陆缘期等演化阶段;在构造特征分析基础上,综合考虑油气成藏要素和运聚方式等特点,划分出新生界构造-岩性圈闭、盐上白垩系构造圈闭和盐下白垩系等三个油气勘探领域;通过各勘探领域油气成藏特征等的系统分析,指出了盆地东部陆上-浅水地区是勘探盐上白垩系构造圈闭勘探领域和盐下白垩系勘探领域的有利地区,盆地西部深水-超深水地区是勘探新生界构造-岩性圈闭勘探领域的有利地区。Lower Congo-Congo Fan Basin,located in the western coast of Africa,is one of the world＇s oil and gas exploration priorities and hot spots in recent years. Being rich in oil and gas and having the giant remnant resource potential,it has long been drawn the great concern from many researchers,and a series of exploration and research work were made from the different aspects such as tectonic evolution,petroleum geology,hydrocarbon migration and accumulation,and resource potential,etc. However,the exploration density is not uniform as the basin covers onshore and offshore which includes shallow water,deep to ultra-deepwater areas from east to west. Therefore,how to fully evaluate the oil and gas remnant resource potential of the basin will be a key factor to guide next exploration deployment in the basin. By the integrated analysis of tectono-stratigraphic framework and basin evolution,it is pointed out that Lower Congo-Congo Fan Basin is a composite petroliferous salt basin superimposed of the Congo Fan Basin on Lower Congo Basin. Taking petroleum geological elements,and features of hydrocarbon migration and accumulation into consideration,three petroleum exploration domains are identified from Lower Cretaceous to Cenozoic,which are the Cenozoic exploration domain related to structural-lithologic traps,the post-salt Cretaceous exploration domain related to structural traps,and the pre-salt Cretaceous exploration domain related to the Early Cretaceous rift,respectively. The subdivision of the three exploration domains lays a sound foundation for systematically evaluating hydrocarbon potential according to the exploratory objectives. By integrated analysis of the petroleum exploration domains,it is pointed out that onshore toshallow water area in the eastern basin is favorable for the post-salt and the pre-salt Cretaceous exploration domains,and deep to ultra-deep water area in the western basin is favorable for the Cenozoic structural-lithologic traps exploration domain.

关 键 词：勘探领域 沉积-构造演化 下刚果-刚果扇盆地 西非 

分 类 号：P618.310[天文地球—矿床学] TE121.2[天文地球—地质学]