15 October 2014

Three great new landslide videos, including a surfing backhoe!

Posted by Dave Petley

A surfing backhoe

The first of these three new landslide videos is a really interesting film of a small landslide taking out a backhoe:


This seems to be a nice example of a slide triggered by excess loading at the crest of the slope – in this case the backhoe itself.  The slide is small, only removing the land on which the excavator is standing.  Note the high mobility of the slide once it starts though.  It is interesting to note that the backhoe remains upright.  The sliding surface is clearly visible at the end of the video – a beautiful illustration of the way that a clay-rich soil can form a low friction sliding plane.

A large landslide in Taiwan

This video is over a year old, but I’ve not seen it previously as far as I’m aware.  This is probably one of the highest quality videos of a large-scale landslide that I’ve seen to date:


The most interesting aspect of this slide is the precursory activity that occurs across the slope before the main collapse event.  It would be really interesting to map this in time and space.  This is I think an indication that the whole block is moving, which as a result is deforming, popping off the smaller failures.  Just before the main collapse small rockfalls and landslides are occurring across the whole slope, as this image shows:



A soil slide from Indonesia

Finally, this landslide video appeared on Liveleak yesterday:


It was reportedly collected in Manado in Sulewesi in Indonesia.  Again, the slope shows lots of precursory landslide activity before the main failure event.  Shortly before the failure a man walks along the road that was subsequently inundated; I wonder whether he managed to escape.  It is interesting to note that the main slide appears to then trigger a second failure on a different part of the slope.  It is not clear to me why this should have occurred.