Hydraulic fracture vertical propagation behavior in transversely isotropic layered shale formation with transition zone using XFEM-based CZM method

The transition zone was defined as an interface with certain thickness, strong heterogeneity and anisotropy in the vertical profile for layered formations, which had great effect on hydraulic fracture (HF) height propagation. In this paper, a numerical model for transversely isotropic layered shale with transition zone was established by utilizing the extended finite element method (XFEM) based on cohesive zone model (CZM). The effects of...