{"id":37508,"date":"2021-04-27T08:04:38","date_gmt":"2021-04-27T08:04:38","guid":{"rendered":"https:\/\/blogs.agu.org\/landslideblog\/?p=37508"},"modified":"2021-04-27T08:07:06","modified_gmt":"2021-04-27T08:07:06","slug":"great-whale-river","status":"publish","type":"post","link":"https:\/\/blogs.agu.org\/landslideblog\/2021\/04\/27\/great-whale-river\/","title":{"rendered":"Great Whale River: a very large, low-angled landslide in Canada on 22 April 2021"},"content":{"rendered":"

Great Whale River: a very large, low-angled landslide in Canada on 22 April 2021<\/h4>\n

On 22 April 2021 a very large landslide occurred on the Great Whale River, upstream from the upstream of the villages of Kuujjuaraapik and Whapmagoostui in Quebec, Canada.\u00a0 Nunatsiaq News has this dramatic image of the landslide<\/a>:-<\/p>\n

\"The

The 22 April 2021 landslide on the Great Whale River in Quebec, Canada. Image by the Whapmagoostui First Nation, via Nunatsiaq News<\/a>.<\/p><\/div>\n

.<\/p>\n

The landslide is located at 55.298, -77.638.\u00a0 It is clearly visible on the Planet Labs image<\/a> taken on 23 April 2021:-<\/p>\n

\"Planet

Planet Labs<\/a> image of the landslide on the Great Whale River. Image copyright Planet Labs<\/a>, used with permission.<\/p><\/div>\n

.<\/p>\n

The slide is large – from the crown to the channel it is about 1.6 km, and from the crown to the toe it is about 4 km.<\/p>\n

The landslide is not thought to pose a direct threat to the communities downstream, fortunately, although there is some risk to users of the river as break-up of the ice is now unpredictable.<\/p>\n

The news reports describes this as having occurred in an area of clay.\u00a0 The form of the landslide suggests that it could be a quick clay \/ sensitive clay failure<\/a>.\u00a0 CBC has a splendid video shot from a helicopter that flew the length of the landslide<\/a>.\u00a0 This is a still from that video:-<\/p>\n

\"The

The landslide on the Great Whale River. Still from a video posted by CBC<\/a>.<\/p><\/div>\n

.<\/p>\n

The video suggests that the downstream\u00a0 deposit is highly liquid mud with rafts of trees.\u00a0 Note that many are still standing upright.\u00a0 This is indicative of a quick clay landslide.\u00a0 The landslide itself appears to be quite deep-seated, probably reflecting a thick clay deposit.\u00a0 This implies that the volume of the landslide on the Great Whale River is likely to be in the millions of cubic metres.<\/p>\n

There is little information as to the likely trigger at this point, but large landslides often occur in the spring as melt occurs.<\/p>\n

.<\/p>\n

Reference<\/h4>\n

Planet Team (2021). Planet Application Program Interface: In Space for Life on Earth. San Francisco, CA. https:\/\/www.planet.com\/<\/a><\/p>\n","protected":false},"excerpt":{"rendered":"

On 22 April 2021 a very large landslide occurred on the Great Whale River in Quebec, Canada. Images suggest that this landslide, which is about 4 km long, was a quick clay slide. <\/p>\n","protected":false},"author":22,"featured_media":37511,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[4,469,959,725,88,29047],"class_list":["post-37508","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-uncategorized","tag-canada","tag-featured","tag-landslide-report","tag-north-america","tag-quick-clay","tag-sensitive-clay"],"_links":{"self":[{"href":"https:\/\/blogs.agu.org\/landslideblog\/wp-json\/wp\/v2\/posts\/37508","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=37508"}],"version-history":[{"count":0,"href":"https:\/\/blogs.agu.org\/landslideblog\/wp-json\/wp\/v2\/posts\/37508\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/blogs.agu.org\/landslideblog\/wp-json\/wp\/v2\/media\/37511"}],"wp:attachment":[{"href":"https:\/\/blogs.agu.org\/landslideblog\/wp-json\/wp\/v2\/media?parent=37508"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/blogs.agu.org\/landslideblog\/wp-json\/wp\/v2\/categories?post=37508"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/blogs.agu.org\/landslideblog\/wp-json\/wp\/v2\/tags?post=37508"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}