25 February 2014

Mount La Perouse rock avalanche: more images

Posted by dr-dave

The Mount La Perouse rock avalanche

The Mount La Perouse rock avalanche nine days ago is a very interesting landslide.  My original post, based on the seismic data of Colin Stark, Clément Hibert and Goran Ekstrom is here; the first images of it, as collected by Drake Olson, are here.

Satellite data

Landsat 8 passed over the landslide on Saturday; nature was kind to us by providing a cloud-free day, so the landslide has been images well.  Colin Stark has run a quick initial process of the data, which reveal the following parameters for the Mount La Perouse rock avalanche:

  • Maximum length (from the crown to the toe: about 7,400 metres
  • Maximum elevation (i.e. height of the crown of the source area): about 2,800 metres
  • Minimum elevation (i.e. the height of the toe of the landslide): about 1060 metres

Colin has draped the Landsat 8 data on to a digital elevation model to provide a view of the dynamics of the landslide:

Mount la Perouse rock avalanche

Copyright Colin Stark, used with permission.  Image: Landsat 8

..

Mount la Perouse rock avalanche

Copyright Colin Stark, used with permission. Image: Landsat 8

..

Some additional images of the Mount La Perouse rock avalanche

Drake Olson, via Marten Geertsema at UNBC, has provided some additional photographs of the landslide.  First, this is a view of the landslide from the air.  Note the remarkable super-elevation of the landslide (i.e. the way in which it has run up the sides of the valley):

Mount la Perouse rock avalanche

Copyright Drake Olson – used with permission

..

This is a really vast landslide.  To give an impression of the scale, this is the landslide toe.  If you look carefully you will just be able to see Drake’s aircraft:

Mount la Perouse rock avalanche

Copyright Drake Olson – used with permission

..

We are all indebted to Drake for collecting these wonderful images.  Here he is sitting on the landslide debris:

Mount la Perouse rock avalanche

Copyright Drake Olson – used with permission

..

Acknowledgements

This post uses images and information collected by Colin Stark.  He would like to acknowledge NSF, which funded the research under the following schemes: