The borehole coal sample gas desorption and tested data from the southern Xiangfen mining area have shown that coal seam methane average content is less than 2ml/g∙daf, average methane concentration only 20.1%. Thus belongs to poorer methane type—dis⁃sipated poor methane type coal reservoir, with maximum depth of gas weathered zone 1 225.5m. The study of main mining coal seam or⁃ganic matter component and maturity has shown that physical property condition of coal seams in the area is better, belongs to medium gas generating reservoir. It has been experienced thermal degradation gas stage, locally can be pyrolysis gas stage. The study has con⁃sidered that post hydrocarbon generation stage tectonic uplift and tensional normal fault intensive development have caused large amount CBM desorbed, dissipated, thus the causation of gas barren in the area.%襄汾矿区南部钻孔煤样瓦斯解吸及测试数据显示，研究区煤层甲烷平均含量均小于2 mL/g·daf，甲烷浓度平均仅为20.1%，属较贫甲烷型—放贫甲烷型煤储层，瓦斯风化带最大深度达1222.5 m。对主采煤层有机质组分及有机质成熟度研究表明，本区煤层物性条件较好，属中等生气型储层，并已经历成气作用的热降解气阶段，局部可达热裂解气阶段。研究认为：生烃期后构造抬升及张性正断层发育密集导致煤层气大量解吸、逸散是本区煤层贫气的成因。
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