煤系气是非常规天然气的重要类型，其成储、成藏是构造沉积作用耦合配置下的结果，尼泊尔低喜马拉雅造山带是研究复杂构造区煤系气储层发育与富集规律的重点区域。以尼泊尔低喜马拉雅造山带Tansen地区Gondwana群和Surkhet群煤系气储层为研究对象，分析了冈瓦纳及前陆盆地煤系气储层类型与组合特征，不同煤系气储层微观孔裂隙形貌发育与孔隙结构特征，探讨了逆冲推覆作用下煤系气储层孔裂隙演化过程与优势孔裂隙形成机制，最后，初步预测了煤系气潜在有利储层、有利区与资源潜力。研究结果表明：① 尼泊尔低喜马拉雅造山带煤系气储层组合类型主要包括“源储一体型”的煤层-页岩气型、“下生上储型”的煤层-致密砂岩气型和页岩-致密砂岩气型以及“源储紧邻型”的煤层-页岩-致密砂岩气型；② 页岩矿物相关的中孔与有机质微孔发育，孔容占总孔容64.6%，比表面积占总比表面积98.1%，煤层主要发育微孔，总比表面积达8.22 m²/g，致密砂岩以粒间孔和微裂隙为主，渗透性在各类储层中最高；③ 页岩孔裂隙具有破坏和新生双重效应，逆冲推覆作用下不同岩性煤系气储层孔裂隙系统演化各异，煤层主要发生构造揉皱作用并发育更多微孔，致密砂岩则主要表现为构造裂隙的形成与扩展；④ Tansen地区东南部Jhadewa矿区是煤系气潜在有利区，Surkhet群Bhainskati组煤层-页岩组合是煤系气优势储层类型，初步估算该地区煤系气资源量达5.04×10⁸ m³。研究旨在初步查明尼泊尔低喜马拉雅造山带煤系气潜在有利储层与有利区，为尼泊尔油气资源评价与勘探研究提供方向。

Coal measure gas is an important type of unconventional natural gas, and its formation and accumulation are the result of the coupling configuration of tectonic sedimentation. The Lesser Himalayan orogenic belt in Nepal is a key area for studying the development and enrichment patterns of coal measure gas reservoirs in complex structural areas. In this study, the coal measure gas reservoirs of the Gondwana Group and Surkhet Group in the Tansen area of the Lesser Himalayan orogenic belt in Nepal were taken as the research objects. The types and combination characteristics of coal measure gas reservoirs in Gondwana and foreland basins were analyzed. The development of microscopic pore-fracture system morphology and pore structure characteristics of different coal measure gas reservoirs were analyzed. The evolution process of pore-fracture systems and the formation mechanisms of dominant pore-fracture systems in coal measure gas reservoirs under the action of thrust nappe were discussed. Finally, potential favorable reservoirs, favorable areas, and resource potential of coal measure gas were preliminarily predicted. The results showed that: (1) The combination types of coal measure gas reservoirs in the Lesser Himalayan orogenic belt of Nepal mainly included the “source-reservoir integration” type of coal-shale gas, the “lower source-upper reservoir” type of coal-tight sandstone gas and shale gas-tight sandstone gas, and the “source-reservoir adjacent” type of coal-shale gas-tight sandstone gas. (2) The mesopores and organic matter micropores related to shale minerals were well developed, accounting for 64.6% of total pore volume and 98.1% of total specific surface area. The coal seam mainly developed micropores, and the total specific surface area reached 8.22 m²/g. In tight sandstones, intergranular pores and microfractures were predominant, demonstrating the highest permeability among all types of reservoirs. (3) The shale pore-fracture system had the dual effects of destruction and regeneration. The evolution of pore-fracture system in coal measure gas reservoirs with different lithologies varied under the action of thrust nappe. The coal seam mainly experienced cataclastic deformation, resulting in the development of more micropores, while the tight sandstones were mainly characterized by the formation and propagation of structural fractures. (4) The coal-shale combination of the Bhainskati Formation of the Surkhet Group in the Tansen area was the dominant coal measure gas reservoir type. The Jhadewa mining area in the southeast of Tansen area was a potential favorable area for coal measure gas. It was preliminarily estimated that the coal measure gas resources in this area reached 5.04×10⁸ m³. This study preliminarily identifies the potential favorable reservoirs and favorable areas of coal measure gas in the Lesser Himalayan orogenic belt of Nepal, providing direction for the evaluation and exploration of oil and gas resources in Nepal.