Analysis of Hydraulic Fracture Propagation Using a Mixed Mode and a Uniaxial Strain Model considering Geomechanical Properties in a Naturally Fractured Shale Reservoir

Abstract

This study proposes a hydraulic fracture propagation model with a mixed mode comprising opening and sliding modes to describe a complex fracture network in a naturally fractured shale gas formation. We combine the fracture propagation model with the mixed mode and the uniaxial strain model with tectonic impacts to calculate the stress distribution using geomechanical properties. A discrete fracture network is employed to realize the fracture network composed of natural and hydraulic fractures. We compare the fracture propagation behaviours of three cases representing the Barnett, Marcellus, and Eagle Ford shale gas formations. Sensitivity analysis is performed to investigate the effects of the geomechanical properties of the reservoir on the sliding mode’s contribution to the mixed mode. The numerical results highlight the significance of the mixed mode for the accurate assessment of fracture propagation behaviours in shale gas formations with high brittleness.

A multi-resolution approach to hydraulic fracture simulation

“…In terms of changes to orientation, several different criteria are typically employed, such as the maximum hoop stress criteria (Erdogan and Sih 1963;Williams and Ewing 1972;Finnie and Saith 1973) or the maximum energy release rate condition (Ewing et al 1976;Cotterell 1965;Hussain et al 1974). Examples of works from the hydraulic fracture field employing such criteria include He and Zhuang (2018), Jang et al (2020) and Grossman-Ponemon and Lew (2019).…”