How does fluid inflow geometry control slope destabilization?

Abstract

Destabilization of submarine slopes and initiation of submarine mass wasting events depend on numerous factors e.g. transient rapid pore pressure changes due to earthquake shaking, fast sediment accumulation, ground water pumping or mineral dehydration to name a few. The major goal of our work is the quantitative analysis of how local pore pressure changes affect the destabilization of stable slope sediments. Here, we report on how the location and extent of fluid inflow within undisturbed slope sediments affect the onset of destabilization. We developed a 2D numerical slope model utilizing a new model approach. We combine a granular model which simulates a sediment package with a gridded fluid flow model. Our results indicate that the entry point of fluid flow greatly changes the location of destabilization. Failure zones of mass movements develop at different places, both vertically and laterally as a function of fluid flow input. Even with a simplified model setup we were able to identify three different destabilization scenarios. © Springer Science + Business Media B.V. 2010.