{"id":26478,"date":"2018-01-04T07:37:15","date_gmt":"2018-01-04T07:37:15","guid":{"rendered":"https:\/\/blogs.agu.org\/landslideblog\/?p=26478"},"modified":"2018-01-04T07:41:01","modified_gmt":"2018-01-04T07:41:01","slug":"karrat-fjord-rock-avalanche-3d-geometry","status":"publish","type":"post","link":"https:\/\/blogs.agu.org\/landslideblog\/2018\/01\/04\/karrat-fjord-rock-avalanche-3d-geometry\/","title":{"rendered":"The Karrat Fjord rock avalanche: a new paper examining the 3D geometry"},"content":{"rendered":"

The Karrat Fjord rock avalanche: a new paper examining the 3D geometry<\/h4>\n

The Karrat Fjord rock avalanche<\/a> was the large, dramatic slope failure in Greenland in June 2017 that generated a localised tsunami, resulting in four deaths.\u00a0 I covered this extensively last year<\/a>, in part because of the dramatic videos of the tsunami itself<\/a>, and in part because of the interesting interpretations of seismic data associated with the landslide<\/a>.\u00a0 We are now starting to see the first papers being published about this slide – I suspect we will see a number over the coming years.\u00a0 I have already highlighted one that examined precursory seismic activity<\/a>.\u00a0 The journal Landslides<\/em><\/a> has now published a paper (Gauthier et al.<\/em> 2017<\/a>) based upon a set of 3D reconstructions of the Karrat Fjord rock avalanche, constructed from aerial imagery collected by helicopter.<\/p>\n

This study starts to provide some very helpful constraints on the landslide. The image below, from Gauthier et al.<\/em> (2017)<\/a> compares a conventional image with the 3D reconstruction:<\/p>\n

\"Karrat

Image from Gauthier et al.<\/em> (2017)<\/a> comparing conventional photography with the 3D reconstruction of the landslide scar for the Karrat Fjord rock avalanche.<\/p><\/div>\n

.<\/p>\n

The statistics for the Karrat Fjord rock avalanche are impressive.\u00a0 In total the team estimate that the landslide had a total volume of 58 million m\u00b3, of which 13 million m\u00b3 was deposited along the track and 45 million m\u00b3 entered the fjord.\u00a0 The landslide had a near vertical release plane at the rear, but was planar in terms of the sliding motion.\u00a0 The majority of the material travelled over 1000 m vertically, with a maximum fall height of 1270 m. In places that landslide was up to 300 m thick.\u00a0 They classify the landslide as a \u201ctsunamigenic extremely rapid rock avalanche”, with the majority of the material entering the fjord in 2-3 minutes.\u00a0 It is unsurprising that a landslide on this scale was able to generate a local tsunami.<\/p>\n

Gauthier et al.<\/em> (2017)<\/a> also comment upon the apparently incipient West Landslide, which can be seen in the image above.\u00a0 They note that this landslide first appeared after May 2015; to date it has moved about 50 m without failing catastrophically.\u00a0 Whilst this landslide appears to be shallower than the main slide, Gauthier et al.<\/em> (2017)<\/a> note that this needs further study.\u00a0 It is hard to disagree.<\/p>\n

I think this is an important study that provides clarity about the nature of the important Karrat Fjord rock avalanche.\u00a0 I hope we will see further studies of the precursory development of the landslide, its motion, and the ways in which it generated the tsunami, in the months ahead.\u00a0 I know that a number of groups are working on this rock avalanche.<\/p>\n

Reference<\/h4>\n

Gauthier, D., Anderson, S.A., Fritz, H.M. et al.<\/em> 2017. Karrat Fjord (Greenland) tsunamigenic landslide of 17 June 2017: initial 3D observations<\/a>.\u00a0 Landslides (2017). https:\/\/doi.org\/10.1007\/s10346-017-0926-4.<\/p>\n","protected":false},"excerpt":{"rendered":"

In a paper just published in the journal Landslides, Gauthier et al. 2017 use a 3D reconstruction to estimate that the tsunamigenic June 2017 Karrat Fjord rock avalanche in Greenland had a volume of 58 million cubic metres.<\/p>\n","protected":false},"author":22,"featured_media":26481,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[544],"tags":[469,5655,959,192,17,136,128],"class_list":["post-26478","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-review-of-a-paper","tag-featured","tag-greenland","tag-landslide-report","tag-paper","tag-research","tag-rockslide","tag-tsunami"],"_links":{"self":[{"href":"https:\/\/blogs.agu.org\/landslideblog\/wp-json\/wp\/v2\/posts\/26478","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/blogs.agu.org\/landslideblog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/blogs.agu.org\/landslideblog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/blogs.agu.org\/landslideblog\/wp-json\/wp\/v2\/users\/22"}],"replies":[{"embeddable":true,"href":"https:\/\/blogs.agu.org\/landslideblog\/wp-json\/wp\/v2\/comments?post=26478"}],"version-history":[{"count":0,"href":"https:\/\/blogs.agu.org\/landslideblog\/wp-json\/wp\/v2\/posts\/26478\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/blogs.agu.org\/landslideblog\/wp-json\/wp\/v2\/media\/26481"}],"wp:attachment":[{"href":"https:\/\/blogs.agu.org\/landslideblog\/wp-json\/wp\/v2\/media?parent=26478"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/blogs.agu.org\/landslideblog\/wp-json\/wp\/v2\/categories?post=26478"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/blogs.agu.org\/landslideblog\/wp-json\/wp\/v2\/tags?post=26478"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}