塞内加尔盆地成藏组合划分与资源潜力评价
Division and Resource Evaluation of Hydrocarbon Plays in the Senegal Basin, West Africa

摘要： 西非塞内加尔盆地是全球近期油气勘探最活跃的前缘盆地之一。基于盆地最新的油气藏数据和勘探成果，应用石油地质综合研究和含油气系统分析的方法，研究了塞内加尔盆地的油气分布规律和主控因素，以成藏组合为评价单元，评估了待发现油气可采资源量，并探讨了盆地油气资源潜力和未来的勘探领域。研究表明，盆地发育3套含油气系统，志留系含油气系统、盐下三叠系含油气系统和白垩系含油气系统，白垩系含油气系统是最重要的含油气系统。区域上，盆地的油气主要分布于毛里塔尼亚次盆和北部次盆；层系上，油气主要储集于上白垩统赛诺曼阶、下白垩统阿尔比阶和中新统；埋深上，盆地油气储量集中分布于1 500~2 000 m和2 000~2500 m。油气富集的主要控制因素是生储盖的有效配置、优质的储层和圈闭及盐活动。资源评价结果表明，塞内加尔盆地待发现石油、天然气和凝析油的可采资源量分别为1 5083×106 bbl、363 Tcf(万亿立方英尺)和3270×106 bbl，合计7 8879×106 boe油当量，最具勘探潜力的成藏组合是上白垩统赛诺曼阶成藏组合和下白垩统阿尔比阶成藏组合。
Abstract: The Senegal Basin in West Africa is one of the most active frontier basin for oil and gas exploration in the world. Based on the newest geological database, with an approach of integrated geological investigation and petroleum system analysis, this paper focuses on the oil and gas distribution patterns and the main controlling factors in the Senegal Basin, and discusses the resource exploration potential in the future. Three petroleum systems are recognized, including the Silurian petroleum system, the presalt Triassic petroleum system and the Cretaceous petroleum system, and the last is of great significance. Regionally, the discovered oil and gas reserves are largely confined to the Mauritania subbasin and Northern subbasin. Stratigraphically, they are mostly reservoired in the Cenomanian, Albian and Miocene. The petroleum reserves are largely reservoired in burial depths: 1,500 to 2,000 m and 2,000 to 2,500 m. The controlling factors of the hydrocarbons in the Senegal Basin include effective sourcereservoirseal assemblage, highquality reservoir and trap as well as salt tectonic movement in salt subbasin. The results of petroleum resources assessment show that undiscovered oil, gas and condensate resources amount to 1,5083×106 bbl, 363 Tcf and 3270×106 bbl respectively in the Senegal Basin. This study proposes two favorable exploration plays: Cenomanian play and Albian play of Cretaceous petroleum system