Résumé
Introduction The role organic-rich shale plays in the production of fossil fuel has tremendously increased in the past decade thanks to recent technological developments that allow an efficient exploitation of this unconventional source rock. Gas shale is composed mostly of minerals but also a carbonaceous substance, called kerogen which is primarily responsible for hydrocarbon storage. As kerogen is encapsulated in a non-permeable mineral matrix, gas and oil recovery operates by means of hydraulic fracturing. One of the many challenges this technique is facing is controlling fracture propagation underground. Understanding how different gas shale components influence the fracture properties of the overall rock is thus of paramount importance for efficient well design. Yet, probing mechanical properties of different gas shale constituents is extremely difficult experimentally due to the very small size of these heterogeneities. In this study, we make use of an alternative approach, based on molecular simulations, to elucidate fracture properties. We apply our methodology to illite, which is the most prominent clay constituent in gas shale, as well as to a composite of illite and a disordered porous carbon modelling kerogen.