Previous works have presented the results of successful simulations of fluid injection into naturally fractured shale using aDiscrete Element Model (DEM). The simulations included coupled fluid flow-deformation analysis, failure type and extentcalculations, as well as a series of parametric analyses. The parameters investigated included: 1) injection rate and its effecton the overall fracturing results, and 2) fluid viscosity, which had a significant influence on the ratio of tensile (mode 1)failure versus shear failure.With the huge growth in the stimulation of naturally fractured formations such as fractured shales, it is clear that the industryneeds new hydraulic fracturing simulation tools beyond the limits imposed by pseudo3D fracturing models. DEMs, in whichboth matrix block behavior and fracture behavior are explicitly modeled, offer one option for the specific modeling ofhydraulic fracture creation and growth in a naturally fractured formation without, for example, the assumption of bi-planarfracture growth.In this paper, we extend the previous works to quantify, for fractured shale gas plays, the effect of stress orientation, fluidviscosity, and rock mechanical properties in terms of changes in fracture aperture and transmissivity. Changes in fracturetransmissivity directly correlate with improvements in well productivity – the primary goal of the stimulation.The results of the study provide a means to improve shale completions by understanding the effects of the DFN orientationrelative to the stress field, fluid viscosity, and rock mechanical properties on changes in fracture aperture, fracturetransmissivity, and formation effective permeability, which directly relate to well productivity.
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