V.V. Pogorelov, V.N. Koneshov, Yu.L. Rebetskiy

In this article the authors discuss a problem of adequate rheologic model of geologic environment for correct influence of gravitation forces on full stress state. The paper shows that the Poisson’s ratio is one of key factors for a model object similar to a physical structure. Another major question for the problem definition of numerical experiments is correct material behaviour after yield strength, influence of fluid pressure and history of processes of deformation and stress. We used FEM-code UWay. Elasto-plastic rheology with Drukker-Prager and Mizes criteria was used for 2D profile that crosses the Westren Sunda subduction zone. Set of strength parameters based on results of reconstruction of natural stress using CMT-mechanisms allowed detection of zones with plastic deformations which correlate with systems of listric faults in the viewed zone. The results are resistant to variations of model regime for oceanic lithosphere. Thus it is a result of complex influence of deformation history and rheologic properties of the model.

Keywords: stress, elastic-plastic deformation, numerical modeling, tectonophysics.