Abstract: Yin'gen-Ejinaqi Basin is a large sedimentary basin with a relatively low degree of oil-gas exploration in China. The exploration practice since the 13th Five-Year Plan(2016-2020) has confirmed that the Cretaceous Baiyingebi Formation is the main source rock series, and three assemblages develops in Carboniferous-Permian, Jurassic, and Cretaceous reservoirs, forming various types of oil-gas pools such as lithological and structural-lithological reservoirs, bedrock buried-hill reservoirs, and unconventional reservoirs. However, the development characteristics of source rocks, main controlling factors of hydrocarbon accumulation, and resource potentials of various sags vary due to the differences of late tectonic movements in Yin'gen-Ejinaqi Basin, thus affecting the overall cost-effective development of the basin. Based on recent exploration practices and understandings, as well as analyses of the basic accumulation conditions, this paper conducted a new round of evaluation on the resource potentials of Yin'gen-Ejinaqi Basin. The results indicate that there is great resource potentials of the Cretaceous lithological and structural reservoirs in Chagan sag, Guaizihu sag, Hari sag, and Tiancao sag, which are the main areas for oil-gas exploration and development. The Carboniferous-Permian buried-hill cave-fractured reservoirs in bed rocks in Lujing sag, Guaizihu sag, and Jigeda sag can provide favorable conditions for high production and hydrocarbon enrichment and are new types of resources for cost-effective exploration. The Cretaceous shale oil and reservoirs in Chagan sag, Guaizihu sag, and Hari sag and the Jurassic lithological reservoirs from the coal-bearing source rocks in Aoxinan sag have certain exploration potential and are new fields for further exploration. In Yin'gen-Ejinaqi Basin, the conventional oil resources amount to 14.39×10⁸t, the conventional gas resources amount to 451.17×10⁸m³, and the unconventional shale oil resources amount to about 5.6×10⁸t, showing excellent exploration prospects.

Key words: Yin'gen-Ejinaqi Basin, new exploration field, accumulation condition, oil-gas reservoir, resource potential

摘要： 银额盆地是中国陆上油气勘探程度较低的一个大型沉积盆地， "十三五" （2016—2020年）规划以来的勘探实践证实，盆地内的白垩系巴音戈壁组是主力烃源岩层系，发育石炭系—二叠系、侏罗系、白垩系3套油气藏组合，形成了岩性、构造-岩性、基岩潜山以及非常规等多种类型的油气藏。银额盆地受晚期构造差异运动影响，其不同凹陷内烃源岩的发育特征、油气成藏主控因素、资源潜力等均呈现出一定的差异性，影响了盆地的整体效益勘探开发。基于近年来的勘探实践和认识，在分析银额盆地油气成藏条件的基础上对其资源潜力进行新一轮评价，研究结果表明：在查干凹陷、拐子湖凹陷、天草凹陷内，白垩系岩性及构造油气藏的资源潜力大，是银额盆地当前油气勘探开发的主要领域；路井凹陷、拐子湖凹陷、吉格达凹陷的石炭系—二叠系基岩潜山缝洞型油气藏具备高产富集条件，是效益勘探的新类型；查干凹陷、拐子湖凹陷、哈日凹陷的白垩系页岩油气藏和敖西南凹陷侏罗系煤系源岩岩性油气藏具备一定的勘探潜力，是下一步探索的新领域。银额盆地的常规石油资源量为14.39×10⁸t、天然气资源量为451.17×10⁸m³，非常规页岩油资源量约为5.6×10⁸t，展现出良好的勘探前景。

关键词: 银额盆地, 勘探新领域, 成藏条件, 油气藏, 资源潜力