Numerical simulation in Applied Geophysics. From the Mesoscale to the Macroscale
Keywords:Poroelasticity, Anisotropy, Fractures, Finite elements, Numerical upscaling
This paper presents a collection of finite element procedures to model seismic wave propagation at the macroscale taking into account the effects caused by heterogeneities occuring at the mesoscale. For this purpose we first apply a set of compressibility and shear experiments to representative samples of the heterogeneous fluid saturated material. In turn these experiments yield the effective coefficients of an anisotropic macroscopic medium employed for numerical simulations at the macroscale. Numerical experiments illustrate the implementation of the proposed methodology to model wave propagation at the macroscale in a patchy brine-CO2 saturated porous medium containing a dense set of parallel fractures.
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