华北安鹤煤田煤储层特征与煤层气有利区分布

Coal Reservoir Characteristics and Perspective and Target Areas for CBM in the Anyang-Hebi Coalfield,North China

通过对安鹤煤田采集煤样的煤质、显微组分、煤相、显微裂隙分析,等温吸附、低温氮比表面及孔隙结构和压汞孔隙结构测试,研究了该区煤层气赋存的地质条件、煤层气生气地质特征和煤储层物性特征。并采用基于G IS的多层次模糊数学评价方法计算了该区的煤层气资源量,预测了煤层气有利区分布。研究结果表明,该区煤层气总资源量为1 115.73×108m3,煤层气资源丰度平均为1.18×108m3/km2,具有很好的煤层气资源开发潜力。在煤田中部的四矿到八矿之间的地区以及北部的水冶镇附近地区,煤层累计有效厚度大、煤层气资源丰度高、煤层埋深适中、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。

Based on the coal quality, maceral, coal facies, micro-fracture, liquid nitrogen isotherm adsorption/ desorption and mercury-injection analyses, the occurrence conditions and generation geological characteristics of coalbed methane （CBM）, coal reservoir physical characteristics, CBM resource and it＇s exploration and exploitation prospect in the Anyang-Hebi coalfield have been 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 resource abundance in the Anyang-Hebi coalfield are about 1, 115.73 × 10^8 m^3 and 1.18 × 10^8 m^3/km^2 respectively, which are very favorable for CBM exploration and development. The optimum target areas in this coalfield are located in the No. 4 mine to No. 8 mine districts of middle coalfield and around Shuiyezhen town in the northern coalfield, where the coal reservoirs have a huge coal thickness and a high CBM resource abundance, a good burial depth, well-connected pore-fracture systems, and a high permeability resulting from the local tectonic stress.