SPICE · Seismic Wave Propagation and Imaging in Complex media : a European network

Final Activity Report Summary - SPICE (Seismic wave propagation and imaging in complex media : a European network)

SPICE joined 14 institutions and several associated partners in the field of computational seismology. The SPICE consortium aimed at integrating institutions with specialisations in physical, mathematical, geological, and computational aspects of wave propagation. The goal was to develop, verify and apply computational tools for wave propagation and imaging problems on all scales. While the research areas involved (from reservoir geophysics, volcanology, earthquake physics to planetary seismology) are all making heavy use of elastic wave propagation phenomena this was the first time that the communities could intensively cooperate and exchange experiences. The SPICE projects covered a wide range of topics, but all made extensive use of three-dimensional (3D) wave simulation technology requiring parallel algorithms implemented on high-performance hardware. The basis for efficient cross-disciplinary use of these tools was the provision of tested wave propagation via the openly accessible SPICE digital library of scientific software (please see http://www.spice-rtn.org online). For the first time, a web-based interactive benchmarking facility for wave propagation and rupture problems was developed that will be the core for future high-performance simulation systems with automated verification facilities. The benchmarks provided for planetary scale seismic tomography, seismic wave propagation and earthquake rupture dynamics, and inversion for earthquake source behaviour have found wide international attention and will continue well beyond the SPICE project. Application of rupture simulation tools led to substantial progress in the understanding of the dynamics of earthquake faults with complex geometries. Novel algorithms led to the discovery of high-frequency radiation from fault kinks contributing to the ongoing discussion on the origin of variations of hazardous strong ground motions near earthquakes. The 3D simulation tools developed within the project allowed an assessment of uncertainties in seismic tomography with a new quantitative level. In order to progress with fundamental questions on geodynamics, accurate knowledge of 3D structure is crucial. These SPICE projects can be considered the foundation for future seismic imaging tools based on the calculation of the complete wavefield in 3D Earth models. As Earth models to be investigated are becoming more and more realistic they also become geometrically more complex. New computational algorithms developed within SPICE now allow for the efficient generation of computational grids using tetrahedral cells. This enables accurate calculations for volcano structures (including surface topography), and complex reservoir as well as fault systems, and sedimentary basin structure with seismic hazard. Using these tools substantial progress could be made in understanding the origin of seismic sources inside volcanoes and wavefield scattering in the Earth's crust and upper mantle. The forecasting of strong ground motions for potential earthquake scenarios in areas with amplifying crustal structure could be taken into a new level in terms of computational accuracy and frequency level achieved. Combined with new imaging technology this will enable much more reliable quantification of ground motions to be expected for characteristic earthquakes. The SPICE project intensified cooperation in the field of computational wave propagation well beyond Europe. In a final joint workshop held in United States in 2007, similar initiatives in other parts of the world as well as the observational infrastructures in seismology were brought together, arranging future collaborative efforts on an international scale aiming for efficient development and use of wave simulation tools.

Data: CORDIS, © European Union