12 December 2015

Two interesting landslide videos from Congjiang, China and Manali, India

Posted by Dave Petley

A rockfall in Manali in India

In India a huge and very dramatic rockfall near to Manali was caught from two different perspectives.  This is a Youtube video from one side:

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With accompanying text that says:

Landslide in Mandi: A massive landslide occurred at the Chandigarh-Manali national highway 21 in Mandi. No casualty has been reported so far.

And this is from the other:

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With accompanying text that says:

Live and Exclusive : landslide near Aut tunnel kullu, Himachal Pradesh (India)

I do think that this is a very interesting pair of videos in many ways.  The main collapse event, as captured in the film, is fascinating.  This is a still from the video as the initial collapse develops:-

Manali

Rockfall at Manali,via Youtube

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And this is a few seconds later:

Manali

Rockfall at Manali

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The rockfall appears to have developed in the lower block, nearer the camera, first, followed by the larger slice, further from the camera, thereafter.  But interestingly the large initial block appears to have failed in one go, before fragmenting, but with the collapse being preceded by many small rockfalls.  This is consistent with an event that is dominated by late stage fracture growth to promote the development of a detachment surface along which the failure occurred.  Once again, road user have been protected by the small pre-collapse rockfalls, which were sufficient to cause road users to evacuate the area, and of course to film with their cameras.

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Congjiang, China landslide video

Meanwhile, another really interesting video has appeared on Youtube courtesy of CCTV, the Chinese broadcaster.  The text that has been posted with it says the following:

 Surveillance camera on a street in Congjiang county in Gansu Province recorded the moment two buildings were destroyed by a landslide on Tuesday morning. After several people on the busy street noticed the landslide, they waved their hands and shouted to the drivers to make the them stop.

The wisdom of the driver who stops and in effect blocks the road just before the landslide is notable!

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