A discontinuous Galerkin fast-sweeping Eikonal solver for fast and accurate traveltime computation in 3D tilted anisotropic media

International audienceWe tackle the challenging problem of efficient and accurate seismic traveltime computation in 3D anisotropic media, by applying the fast sweeping method to a discontinuous Galerkin-based Eikonal solver. Using this method leads to a stable and highly accurate scheme, which is faster than finite-difference schemes for given precision, and with a low computational cost compared to the standard Runge–Kutta discontinuous Galerkin formulation. The integral formulation of the discontinuous Galerkin method also makes it easy to handle seismic anisotropy and complex topographies. Several numerical tests on complex models, such as the 3D SEAM model, are given as illustration, highlighting the efficiency and the accuracy of this new approach. In the near future, these results will be used together with accurate solvers for seismic amplitude and take-off angle computation in order to revisit asymptotic inversion (traveltime/slope tomography) and imaging approaches (quantitative migration involving amplitudes and angles)