[CIG-SHORT] Virtual California 1.0 Released

[Eric Heien]

Greetings,

We are pleased to announce the release of Virtual California, a boundary element code designed to investigate long term fault system behavior and interactions between faults through stress transfer.

Virtual California is a boundary element code that performs simulations of fault systems based on stress interactions between fault elements to understand long term statistical behavior. It uses a model of faults embedded in a homogeneous elastic half space with arbitrary dips and rakes. The code performs calculation assuming linear stress increase in the long term based on element-element interaction calculations governed by Okada’s implementation of Green’s functions. During the rupture phase elements may fail and release stress based on a combination of static and dynamic stress thresholds. The behavior of the system is determined by interactions between elements from the Green’s function and the stress release from elements during events.

Virtual California also includes QuakeLib, a C++ library and Python wrappers containing key mathematics, geophysics and I/O functionality related to earthquake simulation and result analysis. QuakeLib contains 1) functions to read, write and validate fault models and earthquake catalogs in the EqSim format, 2) classes to represent and access these models and catalogs, 3) classes to represent faults and associated fault parameters as well as functionality related to the faults, 4) classes and functions to perform vector mathematics and unit/geographic conversions related to modeling, 5) functions to evaluate stress, gravity, and displacement fields based on Okada’s equations given a rectangular fault or point source.

You can download the source code and manual from:

http://geodynamics.org/cig/software/vc/

Detailed installation instructions for the source are included in the INSTALL file.  Several examples are included and described in the manual.

Best,

Eric Heien
Michael Sachs
Kasey Schultz
John Rundle


References:

Eric M. Heien, Michael Sachs, "Understanding Long-Term Earthquake Behavior through Simulation,” Computing in Science and Engineering, vol. 14, no. 5, pp. 10-20, Sept.-Oct. 2012, doi:10.1109/MCSE.2012.39

Sachs, M.K., Heien, E.M., Turcotte, D.L., Yikilmaz, M.B., Rundle, J.B., Kellogg, L.H. "Virtual California Earthquake Simulator" Seismological Research Letters, November/December 2012, v. 83, p. 973-978, doi:10.1785/0220120052