Hydraulic Fracture Propagation and Fracturing Design Optimization in Deep Coalbed Methane Reservoirs of the Changqing Oilfield

This study presents a novel approach for optimizing hydraulic fracture propagation and fracturing design in deep coalbed methane (CBM) reservoirs, specifically focusing on the Changqing Oilfield in the eastern Ordos Basin. The increasing demand for clean energy underscores the strategic importance of CBM as an unconventional natural gas resource. However, significant variability in fracturing effectiveness has limited efficient production from deep CBM reservoirs. Unlike previous studies that primarily focus on shallow coal reservoirs, this work goes beyond existing efforts by developing detailed structural and geomechanical models incorporating well log data from 31 wells, allowing for a more accurate simulation of fracture propagation under varying fracturing conditions. Through numerical simulations, the study identifies key parameters—such as segment cluster ratio, fluid volume, and injection rate—that significantly influence fracture length and stimulated reservoir volume. The results indicate that optimizing fluid volume and segment cluster ratio can enhance fracture propagation and improve the total stimulated reservoir volume, particularly in reservoirs with stronger rock plasticity and higher permeability. These findings provide valuable insights into the optimization of hydraulic fracturing designs, contributing to improved gas production efficiency and better reservoir stimulation in deep CBM reservoirs.