This blog provides a commentary on landslide events occurring worldwide, including the landslides themselves, latest research, and conferences and meetings. The blog is written on a personal basis by Dave Petley, who is the Wilson Professor of Hazard and Risk in the Department of Geography at Durham University in the United Kingdom.

This blog is a personal project that does not seek to represent Durham University.

Saturday, 30 March 2013

News of the Tibet gold mine landslide

First, many thanks to Adrian Moon for his help in putting together this post.
Xinhua has continued to run various stories about the catastrophic landslide at a gold mine in Medrogungkar, Tibet yesterdayThe sad headline news is that no survivors have been recovered, despite the attention of a large number of rescuers.  Xinhua has also released two tranches of images of the site (here and here), most of which focus on the rescuers in heroic poses.  However, a small number give a better idea of the scale of this event, of which this is by far the best:
http://news.xinhuanet.com/english/photo/2013-03/30/c_132273063_3.htm
Assuming that the source of the landslide is the apparently fresh material on the slope on the right side of the image, this is clearly a very long run out landslide.  The fresh material in the valley is undoubtedly the landslide deposit - it appears that this was a highly energetic, rapid, flow-type event.  It would be really interesting to see an image of the source area, but even from this image it is clear that this is not a typical quarry landslide. The enormous scale of the landslide is shown in this Sky News video:



The most likely location of the landslide, although this is not confirmed, 29.681 degrees E, 91.904 degrees North.  This is the Jiama mine (which elsewhere is sometimes called the Jiama Copper Mine). If so, there is more information about the mine here.  Certainly the satellite image from Google Earth is consistent with the images from Xinhua:

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A Google Earth perspective view demonstrates how a very large-scale slope failure could become channelised in this very narrow, steep valley:



In such a large landslide recovering the victims is a monumental task.  Further updates will be posted on the AGU home of this blog here.

Thursday, 28 March 2013

A new landslide on Whidbey Island

Many thanks to the various people, too numerous to mention, who highlighted this event to me

Whidbey Island in Washington State in NW USA is a well-known landslide site, and indeed has appeared on this blog before.  Yesterday a new landslide developed on a coastal cliff, destroying one house and threatening a further 30 or so.  This appears to be the site before the landslide, as shown on Google Earth:


 There is a really fantastic set of images on the Seattle Times blog, taken from both the air and the ground.  This one gives a really good view of the landslide itself:

http://seattletimes.com/html/photogalleries/localnews2020650059/2.html (c) Ted Warren / AP

An interesting aspect of this is to compare the state of the top of the cliff with that after the landslide.  This is a post landslide view, also from the Seattle Times:

http://seattletimes.com/html/photogalleries/localnews2020650059/2.html (c) Ted Warren / AP

This is a similar view from the Google Earth imagery:


 The length of cliff top lost is actually rather small given the size of the landslide.  This, in this case most of the movement is in material already at the bottom of the cliff rather than a large detachment from the top.  This may well explain why there are no obvious cracks on the Google Earth imagery.

Friday, 22 March 2013

A very important new paper - detecting large landslides using seismic data

ResearchBlogging.orgA paper was published today in the journal Science by Goran Ekstrom and Colin Stark in which they report on the use of the global seismic network to detect very large landslides in remote areas.  Unfortunately the paper (Ekstrom and Stark 2013) is behind a pay wall, so I cannot provide a link to the actual text.  Science have put out a press release about the work, and there are a couple of other news stories about it (here and here for example).  For those that have access to the article, some of the landslides that they describe will be familiar.  You will remember that last summer Colin provided data from his ongoing work with Goran that allowed us to unravel the mystery of the Seti River landslide in Nepal, and subsequently two rock avalanches in Alaska.

Read the rest of this post on the AGU home of this blog by clicking here

Thursday, 21 March 2013

Helicopter images of the Mid-Atlantic ridge in Iceland

I am in the middle of a somewhat chaotic week of travel - Durham, London, Iceland, Durham, London, Padua, London, Brussels, London, Durham, all in a week.  However, this started with an amazing weekend, in which Michele and I went to Iceland to celebrate a significant birthday.  On the day that we arrived, in glorious weather, we chartered a helicopter to fly over the Mid-Atlantic rift and other sites on the so-called Golden Circle. This is a somewhat expensive thing to do, but the views were quite unbelievable and it was a once in a lifetime experience.  I thought I'd reproduce a few of the images here:

So first of all, this was our chariot - a Bell 407.  You will see that we also made a stop on a glacier en route:

Read the rest of this post on the AGU home of this blog by clicking here



Thursday, 14 March 2013

Managing landslide hazard - an example from Franz Josef in New Zealand

Nicolas Barth at the Department of Geology at the University of Otago has a paper (Barth 2013) in the journal Landslides about rock avalanches in New Zealand triggered by the Alpine Fault.  The main topic of the paper is a fantastic ancient landslide known as the Cascade Rock Avalanche.  This image is taken from his website, showing the landslide in all of its glory:



Click here to read the rest of this post on the AGU home of this blog








Friday, 1 March 2013

Landslide oddities part 3: the ground moves in mysterious ways

First, my thanks to Ellen Hardy for pointing this one out.

Actually it is not really a landslide, but it is an example of the "strange" ways that the ground can behave.  The Southern USA has recently been affected by heavy rainfall.  In Leslie, Georgia, a homeowner was somewhat surprised when his empty swimming pool popped out of the ground.  WALB News 10 has the full story with a selection of photographs, although the best one is on the News 8 website, which also has a video:

 
http://www.wtnh.com/dpps/entertainment/must_see_video/heavy-rain-dislodges-swimming-pool-nd13-jos_5632197#.UTBZgtUXKdA
 
Read the full post on the AGU home of this blog by clicking here