%0 Journal Article %T Two-dimensional frequency-domain visco-elastic full waveform inversion: Parallel algorithms, optimization and performance %+ Risques (Risques) %A Brossier, Romain %Z Funded by the SEISCOPE consortium (http://seiscope.oca.eu). %< avec comité de lecture %@ 0098-3004 %J Computers & Geosciences %I Elsevier %V 37 %N 4 %P pp.444-455 %8 2011 %D 2011 %R 10.1016/j.cageo.2010.09.013 %K Seismic wave modelling %K Finite element discontinuous Galerkin %K Multi-parameter seismic imaging %K Quasi-Newton optimization %K Massively parallel computing %Z Sciences of the Universe [physics]/Earth Sciences/GeomorphologyJournal articles %X Full waveform inversion (FWI) is an appealing seismic data-fitting procedure for the derivation of high-resolution quantitative models of the subsurface at various scales. Full modelling and inversion of visco-elastic waves from multiple seismic sources allow for the recovering of different physical parameters, although they remain computationally challenging tasks. An efficient massively parallel, frequency-domain FWI algorithm is implemented here on large-scale distributed-memory platforms for imaging two-dimensional visco-elastic media. The resolution of the elastodynamic equations, as the forward problem of the inversion, is performed in the frequency domain on unstructured triangular meshes, using a low-order finite element discontinuous Galerkin method. The linear system resulting from discretization of the forward problem is solved with a parallel direct solver. The inverse problem, which is presented as a non-linear local optimization problem, is solved in parallel with a quasi-Newton method, and this allows for reliable estimation of multiple classes of visco-elastic parameters. Two levels of parallelism are implemented in the algorithm, based on message passing interfaces and multi-threading, for optimal use of computational time and the core-memory resources available on modern distributed-memory multi-core computational platforms. The algorithm allows for imaging of realistic targets at various scales, ranging from near-surface geotechnic applications to crustal-scale exploration. %G English %L insu-00679644 %U https://insu.hal.science/insu-00679644 %~ INSU %~ UNIV-SAVOIE %~ UGA %~ CNRS %~ UNIV-GRENOBLE1 %~ INPG %~ IRSTEA %~ GIP-BE %~ IFSTTAR %~ AGREENIUM %~ INRAE %~ USMB-COMUE %~ UNIV-EIFFEL %~ IFSTTAR-UNIVEIFFEL