22 July 2020

Qingjiang River: an unusual valley-blocking landslide in Hubei Province, China

Posted by Dave Petley

Qingjiang River: an unusual valley-blocking landslide in Hubei Province, China

On 20 July 2020 a very large landslide occurred in the Enshi Tujia and Miao Autonomous Prefecture in Hubei Province, China, blocking the Quinjiang River. The Xinhua report for this event indicates a volume of about 10 million cubic metres. The main valley was blocked and a barrier lake developed, although it has now breached safely.

I cannot find any images of this landslide in the English language media, which is a shame as it is an impressive event.  A quick search for Hubei landslide in Chinese (湖北滑坡) yields a number of images on Chinese news sites.  This is the best overview of the landslide that I have found:-

Quinjiang River landslide

The 20 July 2020 landslide on the Quinjiang River in Hubei Province, China. Image from Xinhua.

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This appears to be a large, mobile earthflow type landslide,  The nature of the material suggests to me that it is probably a failure in a thick loess deposit, although this needs to be confirmed.  The original failure is surprisingly deep-seated and broad, butt appears that there is little or no failure in the underlying bedrock that forms the gorge.

There is a good drone video of the landslide on Youtube.  You will need to excuse the corny music (I recommend that you turn the sound off), but it provides a really good sense of the nature of the failure.  The blockage on the Quinjiang River had breached at the time of the video:-

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Chine continues to undergo extremely heavy and prolonged rainfall, and there is another Yellow rainfall warning in place today for a large swathe of the country. These conditions are likely to set off an increasing number of landslides.  The combination of saturation to a deep level (as the Qingjiang River landslide indicates) and high intensity rainfall (the current forecast includes rates of up to 70 mm per hour) is ideal for promoting slope failure.

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Quickslide 1: The Skredkallen landslide in Norway

Yesterday, Louise Vick tweeted some nice images of the Skredkallen rock slope failure in Norway.  I’d like to visit this one!

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Quickslide 2: Continued landslide mayhem in Nepal

Nepal continues to suffer a high level of losses from landslides as abnormally heavy monsoon rainfall affects a large part of the country.  Nepal News has a nice summary of the rainfall that is causing these problems. As with China, these issues will become increasing severe as the rain persists.