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arXiv · 1712.06032

Reactivation of Fractures in Subsurface Reservoirs - a Numerical Approach using a Static-Dynamic Friction Model

Runar L. Berge·Inga Berre·Eirik Keilegavlen
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Abstract

Fluid-induced slip of fractures is characterized by strong multiphysics couplings. Three physical processes are considered: Flow, rock deformation and fracture deformation. The fractures are represented as lower-dimensional objects embedded in a three-dimensional domain. Fluid is modeled as slightly compressible, and flow in both fractures and matrix is accounted for. The deformation of rock is inherently different from the deformation of fractures; thus, two different models are needed to describe the mechanical deformation of the rock. The medium surrounding the fractures is modeled as a linear elastic material, while the slip of fractures is modeled as a contact problem, governed by a static-dynamic friction model. We present an iterative scheme for solving the non-linear set of equations that arise from the models, and suggest how the step parameter in this scheme should depend on the shear modulus and mesh size.

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Runar L. Berge, Inga Berre, Eirik Keilegavlen. 2017-12-16. Reactivation of Fractures in Subsurface Reservoirs - a Numerical Approach using a Static-Dynamic Friction Model. https://arxiv.org/abs/1712.06032

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