Morphological Controls on the Occurrence of Submarine Slab Failures

This paper describes a statistical analysis of an inventory of 267 shallow slab slides in the West Nile Delta to identify significant combinations of morphometric parameters deemed conducive to failure. It was found that slopes with a planar plan curvature and a slope angle of less than 6 degrees account for approximately 95% of the observed landslides, and that increasing plan concavity acts to stabilise submarine slopes beyond this 6 degree threshold. It is hoped that these findings will provide a useful starting point in ultimately reconciling geomorphological observation with geotechnical modelling of the sea floor, and thus provide an increased understanding of the controls on submarine slope instability.