Landslides from the 5 September 2022 Luding Earthquake in China

The 5 September 2022 Mw=6.7 Luding Earthquake was a shallow event that struck a mountainous area of Sichuan Province.  The earthquake killed 93 people and left a further 24 missing, with 424 people being injured.  The majority of the death toll was associated with building collapses and landslides, although the breakdown between the two causes is unclear.  It is likely that many of those whose bodies were not recovered died in landslides. I posted some images of the landslides triggered by this event shortly after the earthquake.

The town closest to the epicentre was Moxi [29.59, 102.08] in Luding County, which suffered many landslides.  A new paper in the journal Landslides (Liu et al. 2023) documents these failures, recording 192 landslides in the vicinity of the town.  Most of the failures were small, but they were damaging.

I thought it would be interesting to compare satellite imagery of Moxi town, and its surrounding area, before and after the Luding Earthquake.  This is an area that is heavily affected by cloud, especially in the summer months, so I have chosen two images about a year apart.  This is a Planet satellite image from 21 April 2022:

Planet satellite image of Moxi in Sichuan, China, collected before the Luding Earthquake. Image copyright Planet Labs, used with permission, dated 21 April 2022.

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Whilst this is the same site, collected on

Planet satellite image of Moxi in Sichuan, China, collected after the Luding Earthquake. Image copyright Planet Labs, used with permission, dated 4 May 2023.

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And for reference, as it is easier to compare, here is a slider to compare the two images:

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The large number of landslides that have developed between the capture of the two images is interesting.  Of course, these were not necessarily triggered by the Luding Earthquake given the time gap (they could have been triggered by heavy rainfall, for example), but it is highly likely that the vast majority were coseismic.  There is a large number of shallow disrupted slides in the west of the image, on the steeper slopes into the drainage system (not the optical illusion that makes the valley look like a ridge), and also some landslides on the slopes around the town.

It will be very interesting to see how these landslides develop in the Summer 2023 rainy season.  Debris flows look likely in heavy rainfall events.

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References and acknowledgement

Planet Team (2023). Planet Application Program Interface: In Space for Life on Earth. San Francisco, CA. https://www.planet.com/

Liu, X., Su, P., Li, Y. et al. 2023. Spatial distribution of landslide shape induced by Luding Ms6.8 earthquake, Sichuan, China: case study of the Moxi Town. Landslides (2023). https://doi.org/10.1007/s10346-023-02070-2