Slowflows: Experiments and numerical simulations

Due to various destabilizing factors such as hydro-thermo-mechanical degradation, and earthquakes, the strength of the Earthsurface material may decrease, leading to increased slow earthflow events. Earthflows often cause extensive damage to infrastructure and permanently change the landscape pattern. However, the earthflows have received much less attention compared to their fast-moving counterparts, like avalanches, landslides, and debris flows. Here, we present some novel laboratory experiments simulating slowflows to understand their initiation, movement, and long-term morphological evolution by using a highly viscous material, the molten jaggery, locally found in Kathmandu. The tremendously slowly deforming and moving jaggery is assumed to represent earthflows. Experimental results demonstrate some key aspects of slowflow dynamics of earth materials and seminally contribute to the systematic understanding of earthflow processes. We simulate the slowflow propagation process by using a dynamic earthflow model. Simulation results capture some essential features of the massively viscous, exceptionally slowly deforming, and moving earth surface materials.