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.