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位于湖南中部的涟源盆地，发育一系列北东—北北东向的短轴向斜，面积近６０００ｋｍ２。盆地内有下石炭统侧水组和上二叠统龙潭组两套煤系，煤层主要分布于向斜中。两套煤系的煤层均为腐殖煤，有机质属Ⅲ型干酪根，具较强的生气能力。煤岩中原生小气孔占９０％以上，也有次生气孔和内生、次生裂隙，这就决定了煤层气的赋存以吸附状态为主，游离状态为辅。煤层气的组分主要为甲烷，含微量重烃气及非烃气。煤层的渗透率总体较低，但通过解放储层开采的措施，可显著提高渗透性以利于煤层气的抽放。根据煤层气资源评价结果，可在盆地内划分出３个高、中富气区，而两煤系煤层气的开发远景区均在靠近盆地南缘龙山东西向隆起带的各含煤向斜西南仰起端及其附近。
Located in the central part of Hunan Province, the Lianyuan Basin, the development of a series of North-East-North-East short-axis tilt, an area of nearly 6000km2. In the basin, there are two sets of coal measures, including the Lower Carboniferous Shui Shui Formation and the Upper Permian Longtan Formation. The coal seams are mainly distributed in the syncline. Two sets of coal seam coal are humus coal, organic matter is type III kerogen, with strong ability to generate gas. The primary stomata in coal and rock accounts for more than 90%, and secondary stomata and endogenous and secondary fractures also determine the occurrence of coalbed methane, which is mainly adsorbed and supplemented by the free state. The main components of CBM are methane, trace heavy hydrocarbon gas and non-hydrocarbon gas. The permeability of the coal seam is generally low, but through the measures to liberate the reservoir, the permeability can be significantly increased to facilitate the drainage of coalbed methane. According to CBM evaluation results, three high and middle-rich areas can be divided into two types in the basin. The prospect of coalbed methane in the two coal measures are all located near the coal-bearing syncline southwest of the Longsheng east-west uplift in the southern margin of the basin Start and near.