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.

Wednesday, 30 January 2013

A call for landslide photos for the USGS library archive

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Lynn Highland, a Geographer with the Landslide Program of the U.S. Geological Survey (USGS) is joining the USGS Library in a project to compile an archive of copyright free, high-resolution (if possible) photographs of all aspects of landslides. These contributed photos would be archived permanently with, and obtainable through, the USGS Library website, which can be accessed here:
 
http://libraryphoto.cr.usgs.gov/index.html

The photographs archived at the library are public domain and can be downloaded for free by anyone accessing the website. More information about the library and how it works can also be found at the website.

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

An unusual quarry landslide in Canada yesterday

A somewhat unusual quarry landslide occurred yesterday at the Maskimo Quarry in L'Epiphanie in Quebec, Canada.  Montreal CTV News has a good aerial image of the site and the landslide:
http://montreal.ctvnews.ca/search-suspended-for-workers-missing-in-collapsed-quarry-1.1134230
On initial inspection the slip appears to have originated in the materials in the slope above the main quarry face, and then to have cascaded over the edge into the main excavation. 

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

Tuesday, 29 January 2013

A round up of just a few of the recent landslide events

In the last few weeks there has been an unusual amount of landslide activity worldwide.  This is just a few of the more interesting events, there are many more that I'll try to cover in the next few days.  Thanks to everyone who has pointed them out to e, and apologies if I have not acknowledged your contribution or covered your story yet.  Please do keep them coming!

1. The raw footage of the Mount Dixon Rock Avalanche
The original video of this landslide in New Zealand is now available here (hat tip to Eric Miller for finding this).  It is genuinely amazing.  In fact the motion is even more complex than I had appreciated at first in two ways.  First, in the early part of the video the landslide appears to have a more rapid movement component on the left side (as seen from the camera).  I would not have guessed this from the morphology of the deposit.  Second, the landslide continued to creep for a considerable period after the main motion ceased, and it was this creep that caused the bull dozing of the snow at the landslide snout.  Very interesting indeed, and a perfect illustration of just how complex landslide motion can be.

2. Successful mitigation of the Braldu Valley landslide but continued hardship at Attabad

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

Monday, 28 January 2013

The video of the Mount Dixon (Aoraki Mount Cook) rock avalanche in motion

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At the time of the rock avalanche on Mount Dixon in Aoraki Mount Cook in New Zealand last week it was reported that at least one of the occupants of the Plateau Hut caught the video in action.  This has proven to be the case - 3 News NZ has obtained the footage from the climber - Neil Wiltshire - and has a nice report that features it.  At the moment I cannot embed it, but you can view it here:

View the full post at the AGU home of this blog by clicking here

Friday, 25 January 2013

Another valley blocking landslide in northern Pakistan

Three years ago, In January 2010, a large landslide in Northern Pakistan caused enormous disruption.  The landslide at Attabad, with which this blog was closely involved, remain unresolved, such that it affects the daily lives of thousands of people.  The ever-impressive Pamir Times, and various other newspapers in Pakistan, are now reporting another valley-blocking landslide in the same region, this time at Shigar in Skardu District.  This area is shown on the map below - according to Google Earth Shigar is in the valley above Skardu:

 

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Wednesday, 23 January 2013

An analysis, based on Images and video, of the Mount Cook National Park landslide on Monday

The large landslide on Mount Dixon in the Mount Cook National Park in New Zealand on Monday has now been photographed and videoed in some detail, providing a clearer picture of what happened.  This is a very impressive landslide with a large fall height and long runout distance, although as far as I can see there is nothing surprising about its behaviour.  A good starting reference point is the following Youtube video:



Landslide source
The mass appears to have fallen from a near vertical cliff on the southern flank of Mount Dixon, removing a section of the ridge-top in the process.  The scar left by this section can be seen in the image below (from here):





 

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Monday, 21 January 2013

First reports of a large landslide on Mount Cook in New Zealand

Several newspapers are reporting that a large landslide occurred today on the flanks of Mount Cook.  The best report is in The Press, which has an image (below) and a description of the landslide:
"A Department of Conservation spokeswoman from the Mt Cook office said the rockslide happened just after 2.30pm today.  "It's quite massive and I think it has left a scar on the mountain. I haven't heard of one this big before; not since the one in December 1991." Rocks fell more than 600 metres down the mountain, she said. She said 13 people were staying at the nearby Plateau Hut, but nobody was injured."
 

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Saturday, 19 January 2013

An interesting landslide in the Great Smoky Mountains

On 16th January heavy rainfall in the Great Smoky Mountains National Park in North Carolina triggered a large landslide that destroyed about 200 m of Newfound Gap Road (U.S. 441).  As the National Parks Service estimate that the landslide has a volume of about 70,000 cubic metres, and at least some landslide activity is continuing, it will take a while to reopen the road.  The National Parks Service has very kindly provided the following images of the landslide:





 
See the remainder of the images on the AGU home of this blog by clicking here

Friday, 18 January 2013

There is a very intriguing video on Youtube, posted this week, which provides a series of photographs of a large landslide dam breach event in Peru.  The accompanying text says:
In March 2012 there was a massive landslide in Huaraz, on the famous and breath-taking Santa Cruz Treck [sic]
The video is here:



The location appears to be this valley, as shown in a Google Earth perspective view:

Read more on the AGU home of this blog by clicking here

Wednesday, 16 January 2013

New research: extreme precipitation and landslides in 2010

As regular readers will know, since 2002 I have been maintaining a database of landslides that kill people worldwide (and this work was recently published in the Journal Geology).  In that dataset 2010 is the year with the highest level of losses from rainfall-induced landslides - it truly was a remarkable year.  In a recent paper (available online here and published behind a pay wall in the Journal of Hydrometeorology), Dalia Kirschbaum from NASA and colleagues (Kirschbaum et al. 2012) have used their own catalogue of mass movement events to examine the relationship between landslides and heavy rainfall.  The landslide catalogue that they have used is rather different to mine because it compiles information about all reported rapidly moving landslides, irrespective of their impact.  As such it is more comprehensive than my dataset, although it may be more subject to the vagaries of media and other types of reporting.  In this study, the catalogue has been compared with precipitation data from the TRMM satellite.  The TMPA dataset that they have used combines the TRMM data with rain gauge data to produce daily global rainfall dataset at a resolution on 0.25 x 0.25 degrees.  This dataset is known to represent large rainfall events quite well.

Perhaps unsurprisingly, the landslide dataset used here also show unusually high levels of landslide activity in 2010, with the increase above normal levels occurring primarily in Central America, the Himalayan Arc and Central-Eastern China.  In each case, the authors clearly show that the elevated levels of landslide activity were associated with rainfall levels that were above normal.  So, for example, this is the data for South Asia
 
Read the rest of this post on the home of this blog on the AGU blog site by clicking here

Monday, 14 January 2013

The Yunnan landslide and its relationship to earthquakes

The final count of lives lost in the earthquake in Yunnan Province in China last week is 46 people, of whom 17 were reported to be children.  All of the bodies have been recovered - which given the size of the landslide is a remarkable achievement - but in China there is some controversy about the decision to cremate the remains without the permission of the relatives.  It is not clear why this decision was taken, which does not accord with the religious traditions of the community affected.
Meanwhile, there is more information about the landslide in an article in the Global Times.  This reports that the landslide was 120 meters long, 110 meters wide and 16 meters deep, which seems surprising given the images that first appeared in the aftermath of the landslide:



 

Read more on the AGU home of this blog by clicking here

Friday, 11 January 2013

At least 18 killed in a landslide in China

Chinese News agencies are reporting that a landslide overnight buried 16 households in Gaopo Village of Zhenxiong County, in Yunnan Province, China.  Whilst estimates vary as to the number of known fatalities, CRIEnglish reports 18 confirmed deaths from a total of 40 people buried in the landslide.  On the other hand, China Daily is reporting  16 deaths and 37 people unaccounted for, so it seems inevitable that the fatality count will rise further.

The timing of this event looks interesting and perhaps surprising.  The images of the landslide seem to show a thin covering of quite fresh snow, which is not an obvious condition for landslide triggering.  The overview image, shown below, is also interesting:
http://english.cri.cn/6909/2013/01/11/2702s743084_2.htm
Judging by this image, the landslide was a reasonably rapid flow consisting mainly of mud and soil rather than bedrock:

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

Saturday, 5 January 2013

Remarkable photos of a collapsing arch in California

Robert Wills is a PhD student at Caltech.  On 29th December 2012 he was walking with his family on Tennessee Beach, north of the Golden Gate Bridge in San Francisco, California. This beach features a spectacular arch 30 m above the ground cut into the cliff face.  The day was stormy with large waves. Robert describes on his blog what happened next:
As we were admiring the waves, a crack and the ensuing sound of a waterfall of rocks caught our attention and everyone on the beach spun to see a small stream of rock flowing down the cliff face below the arch. This was exciting enough...
Read the remainder of this post on the AGU home of this blog by clicking here

Friday, 4 January 2013

A round-up of recent landslide stories and incidents

A round-up of recent landslide stories and incidents:

1. Fears of landslides in Rio de Janeiro
January 2011 was marked by a series of terrible landslides in Brazil, that caused extensive loss of life and damage.  Unfortunately, news reports suggest that this area is again suffering very heavy rainfall, with fears that landslides will once again be a major issue.  Hopefully this will come to nothing, but this will be worth watching over the next few days and weeks.

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

The remainder of the post includes:
2. Another landslide in Malaysia
3. An interesting landslide in New Zealand
4. Further landslide problems in the UK

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