Hydraulic fracturing in anisotropic and heterogeneous rocks

In this paper, we present a two dimensional model for modelling the hydraulic fracture process in anisotropic and heterogeneous rocks. The model is formulated using extended finite elements (XFEM) in combination with Newton-Raphson method for spatial and Euler's implicit scheme for time. The fracture is modelled with the help of cohesive zone method (CZM). Anisotropy arising due to orientation of grains in a specific direction in rocks is modelled to understand the influence of the degree of anisotropy and the grain orientation direction on fracture propagation. A combination of Tsai-Hill failure criterion and Camacho-Ortiz propagation criteria is used to predict mixed mode fracture propagation in anisotropic media. Effect of heterogeneities due to material inclusions, on fractures are modelled.