Understanding hydraulic fracturing and associate seismicity – Advanced 3D and 4D FDEM micromechanical modelling
The development of low and ultra-low permeability resources (e.g., shale gas and shale oil) has brought geomechanics to assume a key role for their successful recovery. Especially given recent declines in fossil fuel prices, the industry requires novel and more efficient strategies for the management and exploitation of these resources. Advanced numerical simulations, such as those based on the hybrid finite-discrete element (FDEM) methodology, and innovative experimentations are leading to more reliable geomechanics-based approaches to seismic imaging and reservoir modelling. By providing physics-based understanding on how hydraulic fracturing mechanisms in tight reservoirs are influenced by geology and in-situ stresses, FDEM modelling technology has the potential to advance the frontiers in the interpretation of injection and production data, thus providing a clear process for the optimization of stimulation strategies. FDEM modelling approach can also provide industry with the necessary geomechanical insights and additional capabilities to interpret the monitored microseismicity and, possibly, to evaluate the potential risk associated with induced seismicity. Numerical modelling, coupled with sound experimental validations, can help, for example, operators to associate variations of seismic parameters, such as change in b- and D-values, to specific geological structures and fracture modes, and to better assess the role of critically-oriented fractures on stimulation and production plans.