The Dauki Fault at the Shillong Plateau-Bengal Basin Boundary in Northeastern India: 2D Finite Element Modeling

The Dauki fault is a major fault along the southern boundary of the Shillong plateau that may be a source of destructive seismic hazards for the adjoining areas, including northeastern Bangladesh. In this study, we simulated the present stress distribution and the ongoing convergence deformation within the study area using numerical simulation. This simulation attempts to determine the proper dip angle of the Dauki fault from a variety of differently established models but with the same realistic boundary conditions. The simulated stress field helped to predict the type of tectonic environment and the faulting patterns of the study area. The best-fit model can account for the compressive stress regime in the study area, except in the uppermost part of the Shillong plateau, the Bengal basin, and Assam areas where extensional stress regimes exists. In the model, the elements for which Mohr-Coulomb's failure occurs correspond with the observed earthquake data that refer to the Dauki fault as a north-dipping thrust fault.