CSDMS 2014 annual meeting poster Lian Feng
Modeling the evolution of a thrust system: a geological application of DynEarthSol2D
Eunseo Choi, University of Memphis Memphis Tennessee, United States. echoi2@memphis.edu
Mervin Bartholomew, University of Memphis Memphis Tennessee, United States. jbrthlm1@memphis.edu
Abstract:
DynEarthSol2D (an open source available at http://bitbucket.org/tan2/dynearthsol2) is a robust, adaptive, two-dimensional finite element code that solves the momentum and heat energy balance equations in the Lagrangian form using unstructured meshes. Verified in a number of benchmark problems, this solver uses contingent mesh adaptivity in places where shear strain is focused (localization) and a conservative mapping assisted by marker particles to preserve phase boundaries during remeshing. As a first step towards the ultimate goal of applying DynEarthSol2D to the tectonics-surface process coupling, we explored the factors controlling faulting patterns in a thrust system with multiple décollements. In our models, a décollement is a zone of a finite thickness and a lower cohesion and friction angle than the surrounding rocks. By varying the number of décollements, their frictional strength, and spacing between them, we explore how the factors govern the interaction of décollements, resulting in various styles of deformations in a thrust system. We also investigate how erosion rates and overburden influence thrusting patterns. Our results are compared with balanced cross-sections from the southern Appalachian Mountains. As one of the most intensively studied fold-and-thrust belts, it provides a large variety of thrusting patterns with imbricates branch-off and ramp-flat structures to test our model results.
* Please acknowledge the original contributors when you are using this material. If there are any copyright issues, please let us know and we will respond as soon as possible.
