20 April 2013

Initial reports of landslides from the earthquake in Sichuan this morning

Posted by Dave Petley

The Magnitude 6.6 earthquake in Sichuan this morning occurred just to the southwest of the area affected by the May 2008.  Of course this is not remotely on the scale of that earthquake, but the magnitude and shallow depth will have been sufficient to cause significant damage to the local area.  The USGS shakemap suggests that this will be the distribution of the shaking:

http://earthquake.usgs.gov/earthquakes/eventpage/usb000gcdd#shakemap

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Putting this into Google Earth suggests that the affected area is mountainous, which will inevitably mean that there have been landslides:

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The Vancouver Sun has the first landslide image that I have been able to track down, showing a large block that has fallen onto a road:

http://www.vancouversun.com/news/Photos+China+Sichuan+province+rocked+powerful+earthquake/8269890/story.html

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Xinhua is currently reporting two valley-blocking landslides, plus other failures and rockfalls, but with little detail:

Landslides have blocked traffic in many places across the county and two barrier lakes caused by the landslides are posing risks for the rescue efforts, it said…Vehicles damaged by rolling rocks were seen in the county. Houses along a street in the Lushan county seat have also collapsed. Helicopters are hovering, according to Xinhua reporters at the scene.

This Twitter image purportedly shows buildings in Ya’an – if this is correct (and I am uncertain about this at the moment – but the date is correct)  then it appears that foundation failure has been a major issue:

https://twitter.com/AdamNMayer/status/325430226442129408/photo/1