11 May 2018

Mabian Yi: a massive landslide in China caught on video

Posted by Dave Petley

Mabian Yi: a massive landslide in China caught on video

On Saturday 5th May a very large landslide occurred at Mabian Yi in Sichuan Province, China.  The landslide, which appears to have been anticipated, was captured on a spectacular video that is now on Youtube.  There are multiple versions of this video online, but the best I can find is this one, posted by New China TV:

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There is a longer version of the video, slightly strangely edited, on Twitter as well.  This version shows much more of the precursory rockfall activity that occurred ahead of the main failure event.

This image shows the slope just ahead of the main sliding event:-

Mabian Yi

The slope at Mabian Yi just prior to the landslide on 5th May 2018.  Still from a video posted to Youtube by New China TV.

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Note the recent failure on the left of the image – this slide appears to define the lateral margin of the main failure.  The 5th May landslide appears to have initiated on the right side though:

The initiation of failure at Mabian Yi on 5th May 2018. Still from a video posted to Youtube by New China TV.

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CCTV have a little more detail about the landslide:

A massive landslide on Saturday buried a road section in Mabian Yi Autonomous County in southwest China’s Sichuan Province, terrifying the people who witnessed the disaster.  Soil and boulders estimated over 50,000 cubic meters in volume cut off a nearby road and partially blocked a nearby river.  Learning about the disaster, local government immediately deployed traffic police officers and road maintenance workers to handle the situation.  The police now cordoned off the affected section and the workers are clearing the debris from the road.  No casualties have so far been reported in the disaster.

Waonews report that the location was as follows:

At 12:30 on May 5th, a high slope collapsed (the mileage position of wave three road K6+240~320) at Po three road (pineapple bridge – Sanhekou township) Sanhekou Township, Leshan city of Mabian Yi Autonomous County (pineapple bridge – Sanhekou township).

From this I have been able to track the location down to 28.835, 103.361.  This is an image of the site from Google Earth, captured in 2016:-

Mabian Yi

Google Earth imagery of the site of the Mabian Yi landslide in China.

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Note the apparent tension cracks at the ridge crest.  This was a landslide that has been developing for some time.