A Comprehensive Model for Evaluating Coalbed Methane Reservoirs in China

Coalbed methane reservoir(CBMR)evaluation is important for choosing the prospective target area for coalbed methane exploration and production.This study aims at identifying the characteristic parameters and methods to evaluate CBMR.Based on the geological surveys,laboratory measurements and field works,a four-level analytic hierarchy process(AHP)model for CBMR evaluation is proposed.In this model,different weights are prioritized and assigned on the basis of three main criteria(including reservoir physical property,storage capacity and geological characteristics),15 sub-criteria,and 18 technical alternatives;the later of which are discussed in detail. The model was applied to evaluate the CBMR of the Permo-Carboniferous coals in the Qinshui Basin, North China.This GIS-based fuzzy AHP comprehensive model can be used for the evaluation of CBMR of medium-high rank(mean maximum vitrinite reflectance>0.5%)coal districts in China.