A numerical study of fracture spacing and through-going fracture formation in layered rocks

Naturally fractured reservoirs are an important source of hydrocarbons. Computational models capable of generating fracture geometries according to geomechanical principles offer a means to create a numerical representation of a more realistic rock mass structure. In this work, the combined finite-discrete element method is applied to investigate fracture patterns in layered rocks. First, a three-layer model undergoing layer normal compression is simulated with the aim of examining the controls on fracture spacing in layered rocks. Second, a seven-layer model with low competence contrast is modelled under direct tension parallel to the layering and bending conditions with the focus on investigating through-going fracture formation across layer interfaces. The numerical results give an insight into the understanding of various mechanisms that contribute to fracture pattern development in layered rocks. (C) 2017 Elsevier Ltd. All rights reserved.