Landslides from the 5 September 2022 earthquake in Luding County, Sichuan

On 5 September 2022, at 12:53 pm local time, a M=6.8 (to be confirmed) earthquake struck Sichuan Province in China, with the epicentre located in Luding County at 29.726, 102.279.  At the time of writing the confirmed number of fatalities is 74 according to Xinhua News, with a further 26 people missing.  These numbers are likely to change in the coming days.  Images suggest that there is substantial damage in Luding County.

It is worth noting of course that this disaster comes on top of the ongoing drought and heatwave in China, which also continues to impose severe lock downs on its population in response to Covid-19.  This is likely to have increased both the vulnerability and the long term impact of the seismic event.

The mountainous location of this earthquake has meant that landslides were inevitable.  Images are appearing on Chinese media to suggest that there has been a host of significant failures, causing extensive damage and some evidence of flooding.  For example, JFDaily has a really good set of images of multiple landslides, including this one:-

Landslides in terrace deposits triggered by the 5 September 2022 earthquake in Luding County, China. Image via JFDaily.

.

These appear to be shallow landslides in terrace deposits.  Note the very extensive damage to the road on both sides of the bridge.  The slope has failed both above and below the road.

Meanwhile, BJ News has a report in Chinese about landslides on the Wandong River, reporting that three large landslides have occurred.  The report indicates that at least one was valley blocking, but that the obstruction has been cleared.  The report includes a video showing some of the obstructions, including this dramatic image:-

A valley-blocking landslide on the Wandong River, triggered by the 5 September 2022 earthquake in Luding County, Sichuan. Image from BJ News.

.

Sohu has an annotated image of road damage – unfortunately I cannot translate the text – that is fascinating:-

Landslides triggered by the 5 September 2022 earthquake in Luding County, China. Image from Sohu.

.

The landslides here are shallow, disrupted rockslides, typical of earthquakes in steep mountains.  Note the huge damage to the road.  The slopes on the left have been far more seriously affected than those of the right, possibly suggesting that slope aspect was a factor in initiation (as we have found elsewhere).

For those on Twitter, @Geo_JunXie (a PhD student at the University of Hull, my new institution) has posted a thread of videos of landslides triggered by the earthquake.  They are worth viewing:-

An earthquake of magnitude 6.8 struck near Luding County, Sichuan Province, China today at a epicentre depth of 16 kilometers. The earthquake has triggered a large number of landslides.#earthquake pic.twitter.com/sSbiq26h8c

— JUN XIE (@Geo_JunXie) September 5, 2022

Finally, also on 5 September 2022, at 10:38 am (i.e. before the earthquake), another substantial landslide occurred in China, this time at Shangtan Village in Hualong County in Qinghai Province.  China News has a report that includes this image:-

The 5 September 2022 landslide at Shangtan Village in Hualong County, in Qinghai Province. Image from China News.

.

One person was killed by the landslide.  Note that the failure appears to have occurred in an benched slope.  As per the landslide I featured yesterday at Hongya Village in Qinghai, this may also be a failure in loess, but once again that will need verification.