Modeling Seismic Wave Propagation in Coupled Multiphysics Media With Fracture Structures

For seismic exploration, the coupling problem between different physical fields is unavoidable. The operation of the coupling interface is very tricky. For this challenge, we propose a unified numerical approach to overcome it. Specifically, we construct a model framework, which contains various physical phenomena, and solve it by using the discontinuous Galerkin (DG) method allowing for the jump of the solution across the interface between the fluids and the solid materials. The viscoelasticity and fracture are first incorporated into the coupled model. The model includes the anisotropy, viscoelasticity, and fracture properties. The Riemann solver is employed to handle the coupling interfaces: the acousticelastic contact, the acousticviscoelastic contact, and the elasticviscoelastic contact. Any additional treatment is not required for the complex coupling interface. Several examples are used to demonstrate the validity and flexibility of the proposed numerical scheme, and the corresponding results show that our approach can handle more complex coupled models efficiently.