3 October 2016
The location of the Rizhao rockslide in Shandong
Over the last few days a number of people (see acknowledgements below) have sent details of the location of the Rizhao rockslide in Shandong, about which I posted last week. Please accept my apologies for the slow response – I have just completed an epic journey back from Wellington in New Zealand – which is about as far as you can go from Norwich without using a rocket – so I have a number of important landslides upon which to catch up this week (and thanks to those that have tipped me off about other interesting events). Watch this space. And, as an aside, I am deeply worried about the landslide potential of Hurricane Matthew as it makes landfall over Jamaica and Haiti, probably tomorrow. This has the potential to cause real problems – a direct hit on Haiti could be very nasty.
Anyway, the location of the Rizhao landslide is now clear. Strangely enough it turns out that it is not actually in Rizhao, but in Lanshan at 35.104° N, 119.325° E. This is a Google Earth image of the site from 2012 – clearly a lot of work has been undertaken since then:
Marc comments that:
My guess would be a large wedge style failure. Bedding is clearly visible and would be in a toppling geometry, but the failure plane appears to be on an inclined joint. In such an arrangement removal of material at the toe could provide a release mechanism.
This seems spot on to me. I remain surprised that this is described as a natural landslide when works had obviously been undertaken on the slope. And the image above suggests that this is a slope with a strong set of joints that had the potential to allow release of the landslide.
Similar posts that might be of interest with regard to wedge failures:
- Kalimpong Day 4 part 1: An interesting and deadly roadside landslide
- A major rockslide on US2 near Wenatchee
- The mechanism of the Highway 3 landslide in Taiwan
- Rockfall sequence in Yosemite
Thanks to Marc, Kirk and Jon Johnson, all of whom helped to track down the location of the landslide.