With the huge growth in the stimulation of naturally fractured formations, it is clear that the industry needs new hydraulic fracturing simulation tools beyond the limits imposed by pseudo3D fracturing model. Discrete element models (DEM), in which both matrix block behavior and fracture behavior are explicitly modeled, offer one option for the specific modeling of hydraulic fracture creation and growth in naturally fractured formation without, for example, the assumption of bi-planar fracture growth.

In this paper, we show the results of the successful realistic simulations of fluid injection into a given NFR using the 3DEC DEM model. The simulations included coupled fluid flow-deformation analysis, failure type and extent calculations, as well as a series of parametric analyses. The parameters investigated included: 1) injection rate and its effect on the overall injection results, and 2) fluid viscosity, which had a significant influence on the ratio of tensile (mode 1) failure versus shear failure.

You can access this article if you purchase or spend a download.