|WS13||Friday 03 June 2016|
|Title:||Methods and Challenges of Seismic Wave Modelling for Seismic Imaging|
|Convenors||Romain Brossier (University of Grenoble)
Ludovic Métivier (University of Grenoble)
Mark Huiskes (Shell)
Seismic imaging techniques as Full Waveform Inversion and Reverse Time Migration require simulation of the full seismic wavefields in complex media. With advancing development of computer technology and the exploration of increasingly complex environments, it is now mandatory to tackle larger targets and more complex physics such as visco-elastic waves.
In this workshop, we would like to bring together specialists of the field to discuss the recent developments in seismic modelling and how to incorporate the state-of-the-art techniques into the production imaging workflow. In particular we focus on the host of new challenges in combining accuracy and efficiency of production HPC implementations. This may notably include the following topics and questions.
How to perform numerical simulations in complex media with strong interfaces
- Limits of the acoustic approximation.
- How to mitigate these limits without using full elastic physics?
- Simulation of free surface effects and surface waves for complex topography, possibly in the presence of weathering zones with high Poisson ratios.
- Simulation of water/solid interface for complex bathymetries and soft seabeds.
- Simulation of deep complex body effects (salt).
- What type of methods can provide accurate results that are efficient enough for production use?
- How to combine the near-surface difficulties with deep imaging issues? (adaptive mesh, subgrid description)
How to handle large-scale simulations in the frequency-domain
- How deal with large sparse systems resulting from direct approaches: state-of-the-art and recent developments toward big 3D anisotropic acoustic and 3D elastic in the frequency-domain.
- Direct or iterative approaches?
- Design of preconditioners for iterative approaches.
- Efficient methods for multiple sources.
How to combine efficient forward simulation with requirements of adjoint and gradient computations
- Which wave equation to solve: 1st or 2nd order systems, self-adjoint or not?
- Which spatial discretization method to use : finite-differences, continuous or discontinuous finite element methods?
- Which temporal scheme to use for time-domain approach: second-order or higher-order explicit schemes, implicit schemes?
- How to account for attenuation, what is the impact on adjoint/gradient algorithms?
- How to handle boundary conditions efficiently? (free surface, absorbing boundary conditions, and the impact on the adjoint and gradient?
- What are the algorithmic/HPC issues of gradient computation, e.g. checkpointing strategies ?
Alternatives to volumetric discretization methods
- Hybrid methods and representation of the medium: asymptotic methods for multi-arrivals
- Boundary Element methods
- How to connect simulations performed with different methods into larger simulations?
- Is it possible to represent small scale heterogeneities with subgridding and/or homogeneization techniques?
*If you are interested in attending the workshop, make sure to register as soon as possible via the following webpage.
*A downloadable version can be found here
|Session||Complex Media with Strong Interfaces|
|09:10||WS13 A01 Mimetic Operators for Seismic Exploration
J. de la Puente* (Barcelona Supercomputing Center), O. Rojas (Barcelona Supercomputing Center), M. Ferrer (Barcelona Supercomputing Center) & J. Kormann (Barcelona Supercomputing Center)
|09:40||WS13 A02 A Fast 3-D Free-surface Topography Method for Acoustic Full-waveform Inversion
M.J. Huiskes* (Shell Global Solutions International BV), R.E. Plessix (Shell Global Solutions International BV) & W.A. Mulder (Shell GSI BV & Delft University of Technology)
|10:00||WS13 A03 Simple and Accurate Operators Based on Taylor Expansion for 2D Elastic Seismogram Calculation under Geological Discontinuities with Regular Cartesian Grids
N. Fuji* (Institut de Physique du Globe de Paris (IPGP)), O. Ovcharenko (IPGP/King Abdullah University of Science and Technology), R. Martin (Géosciences Environnement Toulouse) & C. Cuvilliez (IPGP/École Nationale Supérieure de Géologie)
|Session||Towards Elasto-dynamic Full Waveform Inversion|
|10:55||WS13 B01 High-resolution Imaging of Lithospheric Structures Beneath Mountain Ranges by Full Waveform Inversion at Short Period
D. Komatitsch* (CNRS, France), Y. Wang (CNRS, France), V. Monteiller (CNRS, France) & S. Chevrot (CNRS, France)
|11:25||WS13 B02 Efficient Algorithms for Imaging Condition in RTM and Gradient Building in FWI
P. Yang* (Universite Grenoble Alpes), R. Brossier (University Grenoble Alpes), L. Metivier (University Grenoble Alpes) & J. Virieux (University Grenoble Alpes)
|11:45||WS13 B03 Performance Analysis of Discontinuous Galerkin methods for Seismic Wave Propagation
H. Barucq (INRIA), L. Boillot (INRIA), J. Diaz* (INRIA) & S. Ettouati (INRIA)
|12:05||WS13 B04 Exact Boundary Conditions for Local Wave Field Modelling
F. Broggini* (ETH Zürich), M. Vasmel (ETH Zürich), J.O.A. Robertsson (ETH Zürich) & D.J. van Manen (ETH Zürich)
|Session||Seismic Modelling in the Frequency Domain|
|13:40||WS13 C01 Sparse Direct Solvers towards Seismic Imaging of Large 3D Domains
P. Amestoy* (IRIT/University of Toulouse), A. Buttari (IRIT/CNRS), J.Y. L'Excellent (University of Lyon-Inria-LIP) & T. Mary (IRIT/University of Toulouse)
|14:10||WS13 C02 A Fast Iterative Solution of the Time-harmonic Wave Equation with MSSS-preconditioned IDR(s)
M. Baumann* (Delft University of Technology) & M.B. Van Gijzen (Delft University of Technology)
|14:30||WS13 C03 Asymptotically Corrected Reduced Order Modelling for Wavefield Computation with Multiple Sources
V. Druskin (Schlumberger Doll Research), R.F. Remis (TU Delft), M. Zaslavsky (Schlumberger Doll Research) & J.T. Zimmerling* (Delft University of Technology)
|Session||Alternative Methods for Seismic Modelling|
|15:25||WS13 D01 Non-periodic Homogeneization for Seismic Forward and Inverse Problems
Y. Capdeville* (CNRS)
|15:45||WS13 D02 Compact Finite Difference Schemes for the Acoustic Wave Equation
L. Córdova (Departamento de Matemática, Universidad de Oriente), O. Rojas* (Universidad Central de Venezuela), B. Otero (Universitat Politécnica de Catalunya) & J. Castillo (Computational Science Research Center, San Diego S)
|16:05||WS13 D03 A Fast Direct Solver Based on the Boundary Element Method to Model 3-D Elastic Waves in Large Domains
S. Chaillat* (POEMS (CNRS-ENSTA-INRIA)), P. Ciarlet (POEMS (CNRS-ENSTA-INRIA)) & L. Desiderio (POEMS (CNRS-ENSTA-INRIA))
|16:25||WS13 D04 3-D Viscoelastic Time-domain Finite-difference Seismic Modelling Using the Staggered Adams–Bashforth Time Integrator
F. Wittkamp* (Karlsruhe Institute of Technology) & T. Bohlen (Karlsruhe Institute of Technology)