Effect of Changing the Dimension of Initial Debris Mass in the Dynamics of Landslide Generated Tsunami
Date
2021
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
Department of Mathematics
Abstract
Debris
ow is a traveling mass of loose mud, soil, air, water and sand that moves down
a slope caused due to gravity. When debris
ows, landslides, or any gravitational mass
ows hit closed or partially open water sources such as seas, oceans, fjords, hydraulic
reservoirs, mountain lakes, bays and landslide dams, it results in tsunami (impulse water
waves) by transforming their impact energy to water body, potentially causing damages of
infrastructures and human casualties both near eld and the distant coastlines. The degree
of hazard depends on the scale, types, location and process of the landslide. Volume
or size of the initial debris mass that fails in the slope, is one of the dominant factors in
accelerating the splash strength or intensity, the propagation and amplitudes of the subsequent
water waves and potential dam breach or water spill over. Here, we numerically
integrate the two-phase mass
ow model [61] for quasi three dimensional, high-resolution
simulation results with variation of size of the two-phase initial landslide or debris both
longitudinally and laterally. In our numerical experimental results, we observe fundamentally
di erent solid and
uid wave structures in the reservoir, and the dynamics of
submarine mass
ow for di erent volumes of the release mass by extending or contracting
the base area along down-slope and/or cross-slope directions. The simulation results show
that tsunami amplitudes and run out extents are rapidly increased when the volume of
initial release mass in the form of a triangular wedge is enlarged by increasing the base
area through the increment of the length and breadth of the release base. This study can
be an instructive tool to develop and implement tsunami hazard mitigation measures to
enhance public safety and reduce potential loss.
Description
Keywords
Tsunami, Landslide