25 July 2016

Gangotri and China: three fascinating new landslide videos

Posted by Dave Petley

Gangotri – a very nice rockslide video from India

As Asia reels under extraordinary rainfall under strong monsoon conditions, three new, interesting landslide videos have been posted on Youtube.  The first shows a rather elegant rockslide on the highway to Gangotri in Uttarakhand in northern India:

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This is a classic of its type – a translational rockslide on a joint system dipping out of the slope.  It is likely that trimming of the slope to create the road has removed the natural buttress at the toe of the slide, allowing slip to occur on the existing weakness when pore pressures are high.

Gangotri

Gangotri rockslide via Youtube

 

Note also the very large amounts of dust generated by the landslide.

A spectacular landslide from China

This video first appeared on Liveleak, and has now migrated to Youtube as well.  The landslide is from a highway in China, but no other details are available:-

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The magnitude of the landslide is very large.  Note that both section of the landslide occurred on slopes that have been cut to create the road bench, and then reinforced to provide stability:-

Gangotri

Massive roadside landslide in China, via Youtube

 

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The aftermath of a landslide in China

And finally, CCTV has now posted a very nice video of the aftermath of the widely circulated video of a landslide destroying houses in a rural village in Hunan Province:

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This is the original video:

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In this case there is a railway line running across the slope – the failure appears to have occurred at the tunnel portal:

Gangotri

Landslide in China via CCTV and Youtube

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It’s hard to know whether earthworks for the line played a role in the landslide, but it seems like a prime candidate:

Gangotri

Footage of the aftermath of a landslide in China, via CCTV and Youtube

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These three landslides all rather nicely illustrate the ways on which poor slope management is exacerbating landslide problems in upland areas of Asia.