铁法盆地煤层气成藏模式及产能预测

分析了铁法盆地构造形态、沉积环境和聚煤特征 ;研究了盆地水文地质条件和煤层气赋存规律 ,并提出了铁法盆地煤层气成藏模式 .结果表明 :在不对称向斜盆地中 ,沉积了巨厚的下白垩统煤系地层和煤层 ,煤系地层是一个含水层 ,其顶底部含全区分布的隔水层 ,上覆上白垩统含水层 ,有利于煤层气聚集 .侧向上 ,地下水由浅部补给 ,在深部形成滞流 ,在西部煤层分叉尖灭带和相变带附近 ,形成高势能储层 ,因此 ,盆地西部的大兴井田及大隆到大明井田将是煤层气富集高产区 .

Research on Reservoir-Forming Pattern of Coalbed Methane and Productivity Prediction in Tiefa Basin

The tectonic geometry, sedimentary facies, coal accumulation characteristics, hydrogeological characteristics, and accumulation rule of coalbed methane in Tiefa Basin were analyzed. The hydrogeological condition and the occurrence rule of coalbed methane were researched. And the reservoir forming pattern of coalbed methane was suggested. The results show that in this unsymmetrical syncline basin, the thick lower Cretaceous coal measures has been deposited with its roof and floor being confining beds. The overlying upper Cretaceous bed, an aquifer, and the non permeable surrounding rock of the coal seam are helpful for accumulation of coalbed methane. In addition, there is a high potential energy reservoir. So the methane should be rich and productive in the area from Daxin to Daming mining areas in the western basin.