Software
Since approximately 2002, the research group's software packages have been freely available via the Computational Infrastructure for Geodynamics (CIG). There are five main open-source software packages provided:
Adaptable Seismic Data Format
The Adaptable Seismic Data Format (ASDF)
is a modern file format intended for researchers and analysts. It combines the capability to create comprehensive data sets including all necessary meta information with high-performance parallel I/O for the most demanding use cases. Implementations for C/Fortran as well as Python are available.
PYTHON TOOLS
Pyflex (python tool for seismic window selections)
https://github.com/krischer/pyflex
pyadjoint (python tool for constructing adjoint sources)
https://github.com/chukren/pyadjoint
pytomo3d (python tool for seismic data processing)
https://github.com/wjlei1990/pytomo3d
Pypaw (python toolkits for adjoint source tomography data processing on ASDF)
https://github.com/wjlei1990/pypaw
SPECFEM1D
SPECFEM1D simulates seismic wave propagation in a one-dimensional heterogeneous medium. It is a small code that allows users to learn how a spectral-element program is written.
SPECFEM2D
SPECFEM2D simulates forward and adjoint seismic wave propagation in 2D acoustic, (an)elastic, poroelastic or coupled acoustic-(an)elastic-poroelastic media. Meshing is based upon the geometry and mesh generation toolkit Cubit, and the acoustic/(an)elastic/poroelastic solvers are based upon the spectral-element method (SEM). The package may be used to calculate finite-frequency sensitivity kernels and has full adjoint capabilities.
Related link: "Four Applications Sustain One Petaflop on Blue Waters," HPCWire, February 05, 2013.
SPECFEM3D
SPECFEM3D ‘Sesame’ simulates seismic wave propagation in local models, e.g., sedimentary basins or oil & gas reservoirs. Meshing is based upon the geometry and mesh generation toolkit Cubit, and the acoustic/(an)elastic solvers are based upon SEM. The solver may be used to simulate seismic wave propagation on regional and local scales.
SPECFEM3D Globe
SPECFEM3D Globe ‘Tiger’ simulates global and regional (continental-scale) seismic wave propagation. Effects due to lateral variations in compressional-wave speed, shear-wave speed, density, a 3D crustal model, ellipticity, topography and bathymetry, the oceans, rotation, and self-gravitation are all included. The`Tiger' release offers a significant improvement in performance and a more accurate implementation of the crust. It provides a perfectly load-balanced mesh for 3D mantle models honoring shallow oceanic Moho (depths less than 15 km) and deep continental Moho (depths greater than 35 km). Additional new model routines are provided for generic point-profile models (PPM) and Gauss-Lobatto-Legendre (GLL) based models.
The structure of the software has been simplified to facilitate easier implementation of new 3D models. The code accommodates general moment tensors, and provides more complete information in the SAC headers, as explained in detail in the updated user manual. New matrix-matrix multiplication routines help reduce the total number of memory accesses performed in each spectral element and thus significantly improve performance.
FLEXWIN
FLEXWIN automates the time-window selection problem for seismologists. It operates on pairs of observed and synthetic single component seismograms, defining windows that cover as much of a given seismogram as possible, while avoiding portions of the waveform that are dominated by noise. FLEXWIN selects time windows on the synthetic seismogram within which the waveform contains a distinct arrival, then requires an adequate correspondence between observed and synthetic waveforms within these windows.