Fast Finite Element Analysis Method Using Multiple GPUs for Crustal Deformation and its Application to Stochastic Inversion Analysis with Geometry Uncertainty

Crustal deformation computation using 3-D high-fidelity models has been in heavy demand due to accumulation of observational data. This approach is computationally expensive and more than 105 repetitive computations are required for various application including Monte Carlo simulation, stochastic inverse analysis, and optimization. To handle the massive computation cost, we develop a fast Finite Element (FE) analysis method using multi-GPUs for crustal deformation. We use algorithms appropriate for GPUs and accelerate calculations such as sparse matrix-vector product. By reducing the computation time, we are able to conduct multiple crustal deformation computations in a feasible timeframe. As an application example, we conduct stochastic inverse analysis considering uncertainties in geometry and estimate coseismic slip distribution in the 2011 Tohoku Earthquake, by performing 360,000 crustal deformation computations for different 8 × 107 DOF FE models using the proposed method.