9 August 2011

Two new landslide videos – including an amazing pulsing debris flow

Posted by Dave Petley

Another two landslide videos have popped up – and both are fascinating.  First, former Durham student Georgie Bennett captured this multi-stage landslide near to Merano in Italy on 2nd August:

Fortunately no-one was killed.  Note the weather – fine and sunny – so no obvious trigger.

Second, the Pamir Times has today posted this video of a very large debris flow in Talis village, Ghangche District, in the Baltistan region of northern Pakistan.  The Youtube page notes that “At least 60 houses were destroyed by the debris flow disaster that hit Talis village of Ghangche District, in Baltistan region. Last year a similar flood had taken the lives of 13 people at Talis.  Around 120 families of Talis have been evacuated to safe areas, where they are living in tents.”

Do watch this one carefully as it captures beautifully the pulses or waves of movement through the mass, with periods of essentially no movement (actually probably creep) between them.  The different sizes of the pulse mean that each movement event is different in terms of the amount of material mobilised (sometimes material right up to the banks moves, at other times just the material in the centre of the channel), the velocity and the duration.  You will note also that the surface rises as the front of the pulse comes through.  Once you get your eye in, this is quite fascinating and surreal to watch.

Comments and thoughts welcome please!