东非大陆边缘奥加登盆地成藏模式及在油气勘探中的运用  

Hydrocarbon Accumulation Model of Ogaden Basin in East Africa Continental Margin and Its Application in the Oil and Gas Exploration

作　　者：臧晓琳[1] 逄建东[1] 王震[1] 赵云斌[1] 冯晨阳[1] 

机构地区：[1]中海油能源发展股份有限公司工程技术分公司,天津300457

出　　处：《中外能源》2015年第10期45-50,共6页Sino-Global Energy

基　　金：中海油能源发展重大专项"非常规油气勘探关键技术"(编号:WBS:E-J313N020)部分研究成果

摘　　要：奥加登(Ogaden)盆地属于索马里盆地的次盆,截至2013年共钻井34口,其中油气发现井19口,油气显示4口,油气勘探成功率较低。明确研究区油气勘探潜力,落实商业性油气勘探方向是投资者关注的主要问题。在分析奥加登盆地油气成藏条件基础上建立其油气成藏模式,认识到奥加登盆地具有较高的油气勘探潜力。特别是Calub鞍部油气成藏条件优越,Calub鞍部为一继承性发育的正向构造单元,在中深层断裂背斜背景上,浅层形成了大型披覆背斜,存在多套有利的储盖组合,东西两侧发育多套优质烃源岩,烃源岩分布范围广、厚度大、有机质丰度和生烃潜量较高,处于油气运聚的有利指向区,为油气大规模成藏提供了物质基础,是探索中深层天然气和浅层凝析油藏的最佳场所。另外,盆地斜坡带(西部陡坡带和北部缓坡带)紧邻油气形成中心,处于油气集中运移的汇聚型供烃单元内,油气成藏条件优越,也可以作为下步勘探重点区域。Ogaden basin is the sub-basin of the Somali basin.There have been 34 wells drilled by 2013,which include 19 oil and gas discovery wells and 4 oil and gas shows wells.This indicates that the success rate of the oil and gas exploration in the Ogaden basin is low.The major concerns that the investors want to know are the oil and gas exploration potential in the study area and the commercial oil and gas exploration di-rection.Hydrocarbon accumulation model was established based on the analysis of the hydrocarbon accumula-tion conditions in the Ogaden basin.Ogaden basin was then known as the one with high potential of oil and gas exploration.Especially Calub saddle has superior hydrocarbon accumulation conditions and it is an inheri-tance development of positive tectonic unit.A large drape anticline was formed in shallow layers on the back-ground of the middle-deep fault anticline,which has several sets of favorable reservoir-cap combinations.High quality source rocks were developed in the east and west sides of the Calub saddle with wide distribution,large thickness,high organic matter abundance and hydrocarbon potential.It locates in a favorable area of hy-drocarbon migration and accumulation,which provides material foundation for large scale hydrocarbon accumulation.Therefore,Calub saddle will be the best place for the exploration of the middle-deep natural gas and shallow condensate reservoir in the Ogaden basin.In addition,slope belt of the basin（western steep slope belt and northern gentle slope belt） is near hydrocarbon center and in the hydrocarbon supply unit with oil and gas migration,which has good hydrocarbon accumulation conditions and may be the future exploration target.

关 键 词：奥加登盆地 Karoo裂谷 勘探潜力 成藏模式 油气运聚 

分 类 号：P618.13[天文地球—矿床学]