北非特提斯域油气地质特征及勘探方向

Petroleum geology characteristics and exploration prospect in the north Africa Tethyan tectonic domain

北非特提斯域即现今非洲撒哈拉沙漠以北的广阔区域,为冈瓦纳大陆北面与欧亚大陆的南边的宽阔中生代海相沉积带。该地区油气资源丰富,其主要含油气盆地的形成与特提斯洋演化过程密切相关,油气的生、储、盖条件和圈、运、保过程无不受到新古特提斯洋的开裂、扩张、萎缩和闭合过程控制。对特提斯洋演化与北非油气成藏的相互关系进行探讨和分析,认为受特提斯洋演化控制,北非地区构造演化经历了稳定陆块、抬升剥蚀、裂谷裂陷和反转隆升四个阶段;特提斯洋演化有利于北非地区烃源岩、区域盖层和含油构造发育;综合考虑勘探历史和剩余勘探潜力,认为北非西部地区未来的勘探工作应以"上山"(山间盆地)为重点,东部地区未来的勘探工作应向着"下水"(海盆)和"深层系"(古潜山)等领域扩展。

The north Africa Tethyan tectonic domain is now a vast area north of the Sahara desert in Africa, which is a broad Mesozoic marine sedimentary belt north of gondwana and south of Eurasia. This region is rich in oil and gas resources, the formation of main petroliferous basins in north Africa is closely related to the evolution process of Tethys ocean. Both the formation condition of source rock, reservoir, seal and the process of trap, migration, and conservation are controlled by the process of division, expansion, contraction and closure of Tethys ocean. This article investigates and analyzes the interrelationship between the evolution of Tethys ocean and the hydrocarbon accumulation characteristics in north Africa, indicated that, under the control of the evolution of Tethys ocean, the tectonic evolution of north Africa can be divided into four integrated developing phases, including stable continental, uplift and erosion, rift, inverted and uplift. The evolution of Tethys ocean were beneficial to the development of hydrocarbon source rocks, regional caps and oil and gas bearing structure in north Africa. Due to comprehensive consideration of exploration history and residual exploration potential, we hold the opinion that the future exploration work in west part of north Africa should focus on ＂uphill＂（intermountain basin）, and in the east part the future exploration work should expand to the areas of ＂enter the water＂（offshore basin） and ＂go deep＂（buried hill）.