平顶山煤田煤储层物性特征与煤层气有利区预测

通过对平顶山煤田采集煤样的煤质、煤岩显微组分、煤相、煤岩显微裂隙分析, 低温氮比表面及孔隙结构和压汞孔隙结构测试, 研究了该区的煤层气赋存地质条件、煤层气生气地质条件和煤储层物性特征.并采用基于GIS的多层次模糊数学评价方法计算了该区的煤层气资源量, 预测了煤层气资源分布的有利区.研究结果表明, 该区煤层气总资源量为786.8×108m3, 煤层气资源丰度平均为1.05×108m3/km2, 具有很好的煤层气资源开发潜力.其中, 位于煤田中部的八矿深部预测区和十矿深部预测区周边地区, 煤层累计有效厚度大, 煤层气资源丰度高, 煤层埋深适中, 同时由于该受挤压构造应力影响, 煤储层孔裂隙系统发育、渗透性高, 是该区煤层气勘探、开发的最有利目标区. 

Coal Reservoir Physical Characteristics and Prospective Areas for CBM Exploitation in Pingdingshan Coalfield

Based on the elemental, maceral, micro-fracture, coal facies, liquid nitrogen adsorption/desorption and mercury injection analyses, the coalbed methane (CBM) geological characteristics, coal reservoir physical characteristics, CBM resources and its exploration and exploitation prospect in Pingdingshan coalfield were systematically studied. The in-place CBM resource was calculated using the fuzzy mathematics and stacking analysis of GIS (geographic information system) method. The results show that the in-place CBM resources and the resources abundance in Pingdingshan coalfield are about 786. 8× 108 m3 and 1.05 ×108 m3/km2 respectively, which are very favorable for CBM exploration and development. The optimum target areas in this coalfield are the deep prediction districts of No. 8 and No. 10 coal districts, where the coal reservoirs have higher coal thickness and CBM resource abundance, good burial depth, well connected pore-cleat systems, and higher permeability resulting from the tectonic stress.