非洲东、西陆缘油气成藏特征及主控因素对比——以鲁伍马盆地和尼日尔三角洲盆地为例  

HYDROCARBON ACCUMULATION CHARACTERISTICS AND CONTROLLING FACTORS IN EAST AND WEST CONTINENTAL MARGINS OF AFRICA:TAKING RUVUMA BASIN AND NIGER DELTA BASIN AS EXAMPLES

作　　者：张妍[1] 黎明碧[1] 丁巍伟[1] 唐勇[1] 方银霞[1] 

机构地区：[1]国家海洋局第二海洋研究所,杭州310012

出　　处：《海洋地质前沿》2015年第3期33-42,共10页Marine Geology Frontiers

基　　金：国家自然科学基金(41476048);海洋公益性行业科研专项经费项目(201205003;200805078);公益性科研院所基本科研业务专项资金项目(SZ1306)

摘　　要：非洲陆缘的油气资源潜力越来越受到人们的广泛关注,并逐渐成为世界主要的油气产区和投资热点之一。但目前为止,油气产出主要集中于非洲西部陆缘,非洲东部陆缘至今还没有显著的石油发现。以非洲东、西陆缘构造演化为基础,通过对比鲁伍马盆地和尼日尔三角洲盆地烃源岩、储集层、盖层、油气系统及构造圈闭等油气成藏条件,对两者油气资源差异的主控因素进行分析。由于非洲大陆东、西两侧分别与不同的板块相邻,非洲东、西陆缘的形成时间和构造演化不尽相同,导致二者油气资源分布存在较大差异。非洲西部陆缘油气成藏条件优越,优质烃源岩发育,盖层条件较好,油气成藏富集。非洲东部陆缘油气成藏条件较西非差,烃源岩品质不好,火山活动多发,其周围圈闭破坏严重。但可以从西非陆缘成功的勘探经验中得到启发:高品质的烃源岩、可以形成局部盖层和盐构造圈闭的盐层序可能成为未来重点考虑的勘探目标;赞比西三角洲的深水区域可能是今后勘探的重点。The African continental margin is one of the major hydrocarbon producing areas now in the world.However,most of the hydrocarbon resources are found on the west margin of the continent and no giant oil fields have been discovered on the east continental margin up to now.Based on the comparative study of tectonic evolution and hydrocarbon accumulation conditions between the east and west continental margins,such as source rocks,reservoirs,cap rocks and structural traps in the Ruvuma Basin and the Niger Delta Basin,we discussed the major controlling factors for hydrocarbon accumulation in the two typical basins.As we know,the east and west sides of the Africa continent are respectively related to different plates.The difference in forming time and tectonic evolution between the east and west leads to the differentiation of hydrocarbon accumulation.The west continental margin of Africa owes its highly hydrocarbon potential to the excellent source-reservoir-seal assemblages,while the east margin is lack of high-quality source rocks.The multiphase volcanic activities might have destroyed the existed traps.The comparison of the east and west margins of Africa told us that the rich oil and gas on the west continental margin are from the assemblage of high-quality source rocks,the local cap of saline sequences and the traps formed by salt structures.The deepwater off the Zambezi Delta could be a target for future exploration.

关 键 词：非洲陆缘 构造演化 油气成藏特征 主控因素 

分 类 号：P618.13[天文地球—矿床学]