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东尼日尔盆地属于西非裂谷系,是发育于前寒武系—侏罗系基底之上的中、新生代裂谷盆地。该盆地构造演化表现为晚白垩世大规模海侵、早白垩世和古近纪两期裂谷叠置。后期古近纪叠置裂谷发育于广泛分布的晚白垩世海相烃源岩之上,形成主要的成藏组合。国外石油公司自1970年开始对该盆地进行大规模的油气勘探,近40年间,在Termit坳陷西部Dinga断阶带的古近系组合中发现商业油气,其他区域甩开勘探未获突破。中石油于2008年6月获得Termit坳陷的勘探许可,面临着如何在短期内快速评价油气潜力、扩大勘探成果并发现新的含油气区带的难题。对Termit坳陷油气运移和富集规律研究表明,除了西部的Dinga断阶带之外,东部Araga斜坡带也是有利的油气富集区带。以此为指导在Araga斜坡带Dibeilla构造优选部署了Dibeilla-1井,获得重大发现,随后周边滚动探井Dibeilla N-1和Admer-1井也获得商业发现,3口井估算地质储量约0.9×108t。Dibeilla-1井的发现使得Araga斜坡带成为继Dinga断阶带之后的另一个油气富集带,证实了Araga斜坡带的勘探潜力,同时提升了相邻Bilma区块的勘探价值。
The Niger Basin, belonging to the West African Rift System, is a Meso-Cenozoic rift basin developed over the Precambrian-Jurassic basement. The tectonic evolution of the basin represented by Late Cretaceous transgression, and the Cretaceous and Paleogene rifting superimposed. The late Paleogene superimposed rift developed over the widely distributed Late Cretaceous marine source rocks and formed the main reservoir-forming assemblage. Foreign oil companies began large-scale oil and gas exploration of the basin since 1970. During the past 40 years, commercial oil and gas were found in the Paleogene assemblages in the Dinga fault zone in the west of the Termit Depression. No breakthroughs were found in other areas. In June 2008, PetroChina obtained exploration permits in the Termit Depression, facing the challenge of rapidly assessing hydrocarbon potential in the short term, expanding exploration results and discovering new oil and gas zones. Studies on hydrocarbon migration and accumulation in the Termit Depression show that the eastern Araga slope belt is also a favorable oil and gas accumulation zone except for the Dinga fault zone in the west. Using this as a guide, the Dibeilla-1 well was well deployed in the Dibeilla tectonic belt of the Araga slope, where major discoveries were made. Subsequently, commercial discoveries were also made in the peripherally scoured wells Dibeilla N-1 and Admer-1, with estimated geological reserves of about 0.9 × 108t . The discovery of the Dibeilla-1 well made the Araga slope zone another oil and gas rich zone following the Dinga fault zone, confirming the exploration potential of the Araga slope zone and enhancing the exploration value of the adjacent Bilma block.