Co-application of micro-proppant with horizontal well, multi-stage hydraulic fracturing treatments to improve productivity in the Permian coal measures, Bowen Basin, Australia

Abstract

Coal permeability is the key discriminator in well completion selection in coal wells. Low productivity is often attributed to compartmentalisation and pressure-dependent permeability (PDP) effects. Often, vertical well hydraulic fracturing is used to enhance productivity from lower-permeability coals, however, several authors have noted that coal fracture treatments can generate a large unpropped area of stimulated reservoir volume (SRV) that is generated from natural fracture activation and pressure-dependent leakoff. The result of this study confirms previous studies (using radial, cartesian, and enhanced SRV analytic models) that graded particle or micro-proppant injections in conjunction with hydraulic fracture treatments can be a means to enhance coal productivity in PDP-affected or low-permeability coals. In this work, data from the Bowen Basin will be used to investigate the implementation and benefits of micro-proppants in conjunction with horizontal well, multi-stage, hydraulic fracture treatments. The calibrated model will be based on a Bowen Basin case incorporating petrophysical, diagnostic fracture injection test (DFIT), hydraulic fracture, and can utilise production data to constrain modelling parameters. To better understand and provide guidance on co-application of horizontal, multi-stage hydraulic fracturing in conjunction with micro-proppant injections, a range of factors will be evaluated in this model including initial permeability, permeability anisotropy, fracture half-length, area and conductivity of the enhanced region between fractures, lateral length, and the number of fractures. This model will demonstrate the effectiveness, economic benefits, and optimal number of fracturing stages based on the reservoir parameters.