L'EXCELLENT , Jean-Yves

This is the first paper in a two-part series that describes a massively parallel code that performs 2D frequency-domain full-waveform inversion of wide-aperture seismic data for imaging complex structures. Full-waveform inversion methods, namely quantitative seismic imaging methods based on the resolution of the full wave equation, are...

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We present a frequency-domain finite-difference method for modeling 3D acoustic wave propagation based on a massively parallel direct solver. This method was developed as a tool for frequency-domain full-waveform inversion of 3D global offset data that requires an efficient modeling code for multiple shots and few frequencies.We have first...

This is the second paper in a two-part series that describes a massively parallel code that performs 2D full-waveform inversion of wide-aperture seismic data for imaging complex structures. We present several numerical validation of the full-waveform inversion code with both canonical and realistic synthetic examples. We illustrate how...

We present a massively parallel algorithm for distributed-memory platform to perform 2D acoustic frequency-domain Full-Waveform Inversion (FWI) of global offset seismic data. Our code is written in Fortran 90 and uses Message Passing Interface (MPI) for parallelism. The linearized inverse problem is solved by a classical gradient method which...

Three-dimensional frequency-domain full waveform inversion of fixed-spread data can be efficiently performed in the viscoacoustic approximation when seismic modeling is based on a sparse direct solver. We present a new algebraic Block Low- Rank (BLR) multifrontal solver which provides an approximate solution of the time-harmonic wave equation...

Three-dimensional frequency-domain full waveform inversion of fixed-spread data can be efficiently performed in the viscoacoustic approximation when seismic modeling is based on a sparse direct solver. We present a new algebraic Block Low- Rank (BLR) multifrontal solver which provides an approximate solution of the time-harmonic wave equation...

We present a finite-difference frequency-domain method for 3D visco-acoustic wave propagation modeling. In the frequency domain, the underlying numerical problem is the resolution of a large sparse system of linear equations whose right-hand side term is the source. This system is solved with a massively parallel direct solver. We first present...

Wide-azimuth long-offset OBC/OBN surveys provide a suitable framework to perform computationally-efficient frequency-domain full waveform inversion (FWI) with a few discrete frequencies. Frequency-domain seismic modeling is performed efficiently with moderate computational resources for a large number of sources with a sparse multifrontal...

International audience

We present an application of 3D frequency-domain full waveform inversion (FWI) on ocean-bottom cable data from the North Sea. Frequency-domain seismic modeling is performed in the visco-acoustic VTI approximation with a sparse direct solver based on the multifrontal method. The computational cost of the multifrontal LU factorization is...

The solution of sparse systems of linear equations is a key computational kernel in scientific computing. It often represents the most time, memory and energy consuming part of the whole numerical simulation process. In this talk, we focus on sparse direct solvers, and more particularly on MUMPS sparse multifrontal solver...

Frequency-domain Full Waveform Inversion (FWI) is potentially amenable to efficient processing of full-azimuth long-offset stationary-recording seabed acquisition carried out with sparse layout of ocean bottom nodes (OBNs) and broadband sources because the inversion can be performed with a few discrete frequencies. However, computing...