Numerical modelling of a nonplanar strike slip fault and associated stress distribution in lithosphere asthenosphere system

In seismology, the nature of ground deformation in seismically active regions in between two major seismic events has an immense connection with fault movement and other ground damages in those regions. So, understanding of geophysical stress accumulation scenario in this aseismic period and its effects on the faults is a very important aspect for figuring out which faults are most likely to generate further fault movement in future. A computational method during quasi-static, aseismic period in the presence of a strike slip fault and associated fault movement is explained here. A long, surface breaking, non planar strike slip fault is taken to be situated in linearly viscoelastic half space representing the lithosphere asthenosphere system and fault geometry is complex in nature comprising of four interconnected planar parts. Due to some tectonic processes stress accumulates in the vicinity of the fault zone in the aseismic period. Tectonic processes and flow in the Earth's interior drive deformation of the Earth's surface that can lead to destructive fault movement when the accumulated stress exceeds the frictional and cohesive forces across the fault. The problem ultimately reduces to a two-dimensional boundary value problem with some discontinuity across the fault plane. The resulting problem is solved with the help of numerical technique, developed for the purpose, based on finite difference scheme. All the results have been depicted graphically with appropriate model parameters. Computational outcomes reveal that fault movement and fault geometry have a significant effect on the stress, strain and displacement components in the localized area of the fault plane.