This paper presents an analysis of the hydraulic-fracturing stimulations of the coalbed formations of the Bowen Basin of eastern Australia. In particular, two fracturing tests conducted in coal seam No. 4 (Well 3) are analyzed.
The analysis indicates that multiple fractures with horizontal and vertical components are created. A pressure-dependent fluid-loss formulation for naturally fractured reservoirs and a large apparent fracture toughness are necessary to match the observed pressures.
A calibration treatment to determine the fracturing regimes, pressure-dependent permeability, and apparent fracture toughness is proposed for the design and analysis of forthcoming fracturing stimulations. The formulations for these mechanisms are described.