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长庆气田陕１４１井区属于鄂尔多斯盆地靖边三角洲的一部分，上古生界天然气藏的储集体为三角洲平原分流河道砂体及三角洲前缘水下分流河道砂体、河口砂坝相沉积。储集空间主要是充填剩余粒间孔和次生溶蚀孔（包括溶蚀粒间孔、溶蚀粒内孔、铸模孔等）及微裂缝。不同岩石类型的储层具有不同的储集空间组合：岩屑砂岩的储集空间由次生溶蚀孔、晶间孔及微裂缝组成；石英砂岩则由充填剩余粒间孔、粒间溶蚀孔及高岭石晶间孔组成。储层孔喉半径偏小，孔喉结构复杂；孔隙度一般为４％～８％，渗透率一般为０．１×１０－３～１×１０－３μｍ２，属于低孔低渗储层。研究认为，该区气藏类型为岩性圈闭气藏。盖层与储层的组合方式、盖层的封闭能力及盖层的分布面积是控制气藏形成的关键。气藏的分布受网状河道砂岩体的控制。
The Shaan-141 well of Changqing Gas Field belongs to the Jingbian delta of Ordos Basin. The reservoirs of the Upper Paleozoic gas reservoir are delta plain distributary channel sand bodies and delta front distributary channel sand bodies and estuary sand bar facies. The reservoir space is mainly filled with the remaining intergranular pores and secondary dissolution pores (including intergranular pores, erodible pores, mold holes, etc.) and microcracks. Reservoirs with different rock types have different combinations of reservoir space: the fractured sandstone reservoirs consist of secondary dissolution pores, intergranular pores and micro-fractures; quartz sandstone is composed of the remaining intergranular pores, intergranular dissolution pores and Kaolinite intergranular pore composition. The reservoir throat radius is small and the pore throat structure is complex. The porosity is generally 4% -8%, and the permeability is generally 0.1 × 10-3 ~ 1 × 10-3μm2, which belongs to the low porosity and low permeability reservoir. According to the research, the type of gas reservoirs in this area is lithologic trap gas reservoir. The combination of cover and reservoir, the sealing ability of cover and the distribution area of cover are the keys to control the formation of gas reservoir. The distribution of gas reservoirs is controlled by reticular channel sandstone bodies.