浅议我国低煤阶地区的煤层气勘探思路

Discussion on finding coalbed methane in low rank coal in China

通过对高煤阶沁水盆地和低煤阶准噶尔、吐哈等盆地水文地质条件的分析发现,把这种勘探思路(地层水矿化度高值区是煤层气勘探最有价值的区域之一)运用到低煤阶的煤层气勘探中却很难,因为低煤阶一般经历了较浅的埋藏深度,煤层热演化程度较低,其生气量较小,煤层气富集成藏的关键在于其生气条件.本文认为:水文地质条件在高低煤阶煤层气富集成藏中所起的作用是不同的,低煤阶勘探中对水文地质作用的认识要从另外一个角度来审视,较为活跃的水动力条件是有利的,活跃的、低矿化度的地层水有利于二次生物气的生成.

Based on the analysis of the hydrogeological condition on Qinshui Basin, Junggar Basin and Tuha Basin, it is difficult to apply this acquisition （combed methane area with high formation water salinity is favorable area for combed methane exploration） to low coal rank area, because low rank coal suffered shallower buried depth and low evolvement degree and has low gas content. The quantity of gas generated is key factor for low rank coal. In the end, the author thought that formation water played a different role in low and high rank coal. In low rank coal, active formation water is a positive factor and in favor of secondary gas generation.