15 May 2019
Joffre Peak: a significant rock avalanche in Canada
Posted by Dave Petley
Joffre Peak: a significant rock avalanche in Canada
Update: an even larger rock avalanche occurred on Joffre Peak on 16th May 2019.
On Monday morning (13th May 2019) at 07:41 am local time, a significant rock avalanche occurred at Joffre Peak in British Columbia in Canada. This has been well-reported in the local newspapers – for example, City News 1130 has a good report, including links to seismic data that recorded the event. Chris Christie posted this image of the source of the landslide and the initial part of the track:-
The source and initial track of the rock avalanche at Joffre Peak. Image by Chris Christie, South Coast Touring Facebook Group via Reddit
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Meanwhile, BC Parks have released this image of the track of the rock avalanche at Joffre Peak:-
The track of the rock avalanche at Joffre Peak in Canada. Image via the BC Government.
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Dr Drew Brayshaw has undertaken an initial analysis of the landslide, and tweeted that the failure area was about 25,000 – 30,000 m², based on a failure geometry of a block approximately 200 m high and 150 m wide. The runout distance was about 4.2 km. The location is 50.343, -122.446 if you want to take a look in Google Earth. The landslide is likely to have entrained a large volume of material along its track, although we will need to wait for good satellite images until this can be determined properly. No lives have been lost, but there has been some disruption to power supplies.
Once again we see a large rock avalanche in a high mountain area in the spring time, so it is logical to think that this might have been associated with melting ice in the rock mass. Interestingly, British Columbia has been experiencing unusually high temperatures – on Thursday last week a number of temperature records were broken, with temperatures in some locations reaching 30 C.
British Columbia experiences frequent large landslides – notable events include the 2012 Johnsons Landing landslide and the dramatic 2010 Meager Creek rock avalanche.
Update: an even larger rock avalanche occurred on Joffre Peak on 16th May 2019.
Dave Petley is the Vice-Chancellor of the University of Hull in the United Kingdom. His blog provides commentary and analysis of landslide events occurring worldwide, including the landslides themselves, latest research, and conferences and meetings.
Interesting article
Maybe a larger volume? With an L/H of about 3.6 and these very impressive/interesting pictures from Jay Memay: https://www.facebook.com/jmemay/posts/10156268455831512
Hi Dave,
it seems that the link to Meager Creek rock avalanche is the same than Johnsons’ one…
[sorted, thanks. D.]
It looks like another, potentially larger slide occurred on the same face today. Impressive.
Hi Dave,
Looks like another section located just left of the previous slide collapsed earlier today. The new scar seems to be twice as big.
It seems that there has been a SECOND event. Possibly larger? An update would be very cool!
Thanks!
The heli video seems to show some large flat tabular blocks in the debris field starting at :27. I’m curious if those are a function of snow collapse under the debris, or actual rock bodies
Nice blog!
Here is a lesser known large rockslide over a glacier in BC, but one that fell in the Autumn:
Jiskoot, H. (2011). Long‐runout rockslide on glacier at Tsar Mountain, Canadian Rocky Mountains: potential triggers, seismic and glaciological implications. Earth Surface Processes and Landforms, 36(2), 203-216. https://doi.org/10.1002/esp.2037
On 13/05 Monday afternoon walked up to the Upper Joffre Lake, all paths open and no mention of the landslide on the opposite side of the mountain. Came as a bit of a surprise to read this but there was no obvious falls onto the glacier above the upper lake.