Evaluation of Heterogeneity in Tectonically Deformed Coal Reservoirs Based on the Analytic Hierarchy Process-Entropy Weight Method Coupling Model: A Case Study

This article presents a comprehensive analysis of the factors influencing the heterogeneity of tectonic coal reservoirs, focusing on the metamorphic degree and pore-fracture parameters of tectonic coal. To ensure a reliable evaluation, the AHP-EWM coupling evaluation model (analytic hierarchy process and entropy weight method), which integrates the strengths of both evaluation models and minimizes the potential errors associated with a single model, was employed to assess the heterogeneity index of coal reservoirs in the Panguan syncline. According to the findings of the AHP-EWM model, it was observed that the comprehensive index of coal heterogeneity consistently increases as the degree of coal deformation increases. Notably, a critical value of I = 0.48 was identified as the threshold for the comprehensive index of brittle and ductile deformation coal heterogeneity. Furthermore, the pore-fracture characteristic was determined to have the greatest effect on the heterogeneity of coal reservoirs, followed by the metamorphic degree. This research contributes significantly to the identification of high-quality coalbed methane reservoirs in the Panguan syncline of western Guizhou, serving as a valuable point of reference.