Thrase

About

Thrase is a GPU-enabled, high-order accurate SBP-SAT finite difference code on unstructured meshes for SEAS (Sequences of Earthquakes and Aseismic Slip) problems written entirely in Julia.

Features:

• high-order accurate finite difference spatial discretizations featuring provably stability
• direct and matrix-free iterative solvers for static problems via Julia
• non-stiff methods for fully-dynamic (wave propagation) problems involving rate-and-state friction
• high-order accurate, adaptive time-stepping via Julia
• unstructured hexahedral meshes
• non-planar boundaries and interfaces

Dependencies:

• Thrase is written entirely in Julia

Installation:

As a julia registered package (recommended):

• Download the latest release of Julia
• Coming soon!: add the Thrase package: from the julia repl:

] add Thrase

• Test the installation:

] test Thrase

From source (in your terminal):

• Download the latest release of Julia
• Clone the repository

git clone https://github.com/Thrase/Thrase.jl.git

• Activate the project and download and compile dependencies

cd Thrase.jl
julia --project=.
] activate .

• Install any dependencies (only necessary the first time)

] instantiate

• Test the installation

include("test/runtests.jl");

Getting Started:

To run the code for the first SEAS benchmark problem

localARGS = ["examples/bp1-qd.dat"]
include("examples/stripped_qd_driver.jl");

To run the code for BP6

localARGS = ["examples/bp6.dat"]
include("examples/BP6_driver.jl");

Note that the parameters set in the input file "examples/bp1-qd.dat" are slightly modified from the benchmark description to allow for fast simulation on most personal computers. The driver file calls a stripped down version of the code (for training purposes).

Documentation:

More to come soon...

How to cite:

• Erickson, B. A., Kozdon, J. E., and Harvey, T. (2022), A non-stiff summation-by-parts finite difference method for the wave equation in second order form: Characteristic boundary conditions and nonlinear interfaces, Journal of Scientific Computing, doi: 10.1007/s10915-022-01961-1.
• Kozdon, J. E., Erickson, B. A., and Wilcox, L. C. (2020), Hybridized summation-by-parts finite difference methods, Journal of Scientific Computing, doi: 10.1007/s10915-021-01448-5.
• Erickson, B. A. and Dunham, E. M. (2014), An efficient numerical method for earthquake cycles in heterogeneous media: Alternating sub-basin and surface-rupturing events on faults crossing a sedimentary basin, Journal of Geophysical Research, doi:10.1002/2013JB010614.

License:

• Distributed under the MIT License. See LICENSE.txt for more information.

Contributing:

Thrase is an open-source project and welcomes:

• contributions via forks and pull requests
• questions, feature requests, or bug reports via issues

Contact:

• Brittany A. Erickson (bae@uoregon.edu)