Escript-downunder: Large-scale inversion on parallel computers


The downunder module provides a collection of high-level tools for 3D inversion of geophysical data using the finite element method. It follows an open design approach to give users easy ways to extend capabilities. The tool kit is based on the escript module for numerical modeling which, through its python-based user interface, provides a convenient high-level interface to build complex inversions and at the same time to make efficient use of desktop computers and HPC facilities with thousands of cores.


Figure 1. Results of a joint inversion of gravity and magnetic field anomaly data over a region of about 100km by 100km. The colours indicate the magnetic susceptibility variation to a depth of 30 km.


Figure 2. Inversion of gravity anomaly data. The contour plot of the inversion results (bottom) show the density anomalies in the subsurface (blue=negative, red=positive)


  • Python-based user interface

  • Finite Element Method (FEM)

  • optimized for large data sets

  • Virtual Geophysics Laboratory (VGL) integration

  • gravity and magnetics

  • joint inversions with multiple data sets

  • extendable inversion capabilities

  • open design with symbolic computing

  • scalable performance with 8000+ processor cores

  • integration with advanced 3-D visualization

  • supported formats: netCDF, Silo, VTK, ER Mapper, ...

  • Open Source License

  • compatible with Linux, Mac, Windows


The code can be downloaded from

License: Open Software Licence v 3.0


Project funded by the Australian Geophysical Observatory System (AGOS), AuScope NCRIS, CRIS, NCRIS2.