sunset_kauai (c) Bridget Smith-Konter

Maxwell: 4D Viscoelastic Crustal Deformation Modeling Code

Exploration of earthquake scenarios that span several thousand years, and deform over an equal number of kilometers, requires models that are three-dimensional, time-dependent, and computationally efficient. My groupʻs research focuses on the development, verification, & application of a semi-analytical Fourier model describing the 3D response of both elastic and viscoelastic mediums to a distribution of body forces. Using Fourier analysis, the horizontal complexity of a given fault system has no effect on the speed of the computation; likewise, because the solution is analytic in time, no numerical time stepping is required. This approach allows for rapid computer model calculations that are over 20 times faster than previous methods (e.g., finite element methods). A single time-step for a mesh of 2048 by 2048 horizontal grid cells, containing over 400 fault patches, requires only 40 seconds of CPU time on a personal computer. Multiple time steps, including hundreds of years of earthquake history, can be computed in a matter of hours.

Maxwell sketch
Plate Motion

Model documentation and FORTRAN source code

Related Publications:

  • Ward, L., B. Smith-Konter, X. Xu, X. Tong, and D.T. Sandwell (2021), Seismic moment dependence on crustal rigidity for the southern San Andreas Fault System, Journal of Geophysical Research, https://doi. org/10.1029/2020JB021208.
  • Sandwell, D.T. and B. Smith-Konter (2018), Maxwell: A semi-analytic 4-D code for earthquake cycle modeling of transform fault systems, Computers and Geosciences, doi: 10.1016/j.cageo.2017.737.
  • Smith, B. and D. Sandwell (2006), A model of the earthquake cycle along the San Andreas Fault System over the past 1000 years, J. Geophys. Res., 111, doi:10.1029/2005JB003703.
  • Smith, B.R. and D.T. Sandwell, A 3-D semi-analytic viscoelastic model for time-dependent analyses of the earthquake cycle, J. Geophys. Res., doi:10.1029/2004JB003185, 2004.
  • Smith, B. R. and D. T. Sandwell, Coulomb stress along the San Andreas Fault System, J. Geophys. Res., 108, doi:10.1029/2002JB002136, 2003.