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塔里木盆地西南坳陷地区的石炭系石英砂岩为一套分布稳定的滨浅海相碎屑岩沉积，在不同地区均具有相似的初始孔隙度。但在成岩期间，由于受构造活动的影响，在塔西南坳陷内部形成了两个重要的次级构造单元，即巴楚隆起区和麦盖提斜坡区，从而导致石炭系石英砂岩经历了不同的埋藏成岩环境的改造，具体体现在其成岩演化序列上具明显的差异性。在巴楚隆起区石炭系砂岩经历了稳定的持续埋藏成岩环境的改造，其成岩演化序列比较完整，各种成岩矿物的溶解、沉淀均在水－岩两相反应系统中进行，成岩阶段可达晚成岩阶段Ｂ期，甚至Ｃ期，因此砂岩原生孔隙破坏严重，平均孔隙度小于５％。而在麦盖提斜坡区，石炭系石英砂岩由于埋藏成岩深度始终小于隆起区，因此其成岩阶段多分布在晚成岩Ａ期－Ｂ期，特别是石油侵位作用的影响，使成岩反应在水－油－岩三相介质中进行，从而抑制了多数自生粘土矿物的沉淀作用，导致成岩演化序列的不连续性，但同时又保存了许多有效的储集空间，使该区砂岩平均孔隙度保持在７％±，高于隆起区，据此认为麦盖提斜坡区是近期在石炭系砂岩储层中进行油气勘探的最有利区域。
The Carboniferous quartz sandstone in the southwest depression of Tarim Basin is a set of stable coastal shallow marine clastic sediments with similar initial porosity in different regions. However, during the diagenesis period, two important secondary structural units were formed in the southwestern Tarim basin due to the tectonic activities, ie, the Bachu uplift and the Maigaiti slope, which led to the different carboniferous quartz sandstone The reconstruction of the burial diagenetic environment is embodied in the obvious differences of diagenetic evolution sequences. The Carboniferous sandstone in Bachu uplift experienced a stable continuous burial diagenetic environment with relatively complete diagenetic evolution sequence. The dissolution and sedimentation of various diagenetic minerals are all carried out in the water-rock two-phase reaction system, and the diagenetic stage is reachable Late diagenetic stage B, or even C, so the sandstone primary pore damage serious, the average porosity of less than 5%. In the Mageti slope area, the diagenetic stage of Carboniferous quartz sandstone is always smaller than that of the uplift. Therefore, the diagenetic stage is mainly distributed in the late-diagenetic stage A-B, especially the petroleum emplacement. - oil-rock three-phase medium, thereby inhibiting the sedimentation of most authigenic clay minerals, leading to the discontinuity of diagenetic evolution sequence, but at the same time preserving many effective reservoir spaces, keeping the average porosity of the sandstone in this area At 7% ±, higher than the uplift, it is considered that the most favorable area for oil and gas exploration in the Carboniferous sandstone reservoirs is the Margaret area.