{"id":7479,"date":"2013-12-17T15:31:38","date_gmt":"2013-12-17T15:31:38","guid":{"rendered":"http:\/\/blogs.agu.org\/landslideblog\/?p=7479"},"modified":"2013-12-17T15:31:38","modified_gmt":"2013-12-17T15:31:38","slug":"tohoku-earthquake-landslide","status":"publish","type":"post","link":"https:\/\/blogs.agu.org\/landslideblog\/2013\/12\/17\/tohoku-earthquake-landslide\/","title":{"rendered":"The 500 cubic kilometre landslide that we all missed – triggered by the Tohoku earthquake"},"content":{"rendered":"
The Tohoku Earthquake tsunami<\/h5>\n

The UK environment research council NERC has a press release out today about work that was presented last week at the AGU Fall meeting in relation to the Tohoku earthquake in Japan.\u00a0 There has been some investigation of the terrestrial landslides triggered by the event, but of course most of the interest has been focused on the tsunami.\u00a0 There has always been something of a mystery about the Tohoku earthquake tsunami, in part because it was so large and in part because its behaviour is a little strange.\u00a0 In particular, the tsunami had two distinct peaks some 20 to 30 minutes apart.<\/p>\n

\"Tohoku<\/a><\/p>\n

..<\/p>\n

A giant submarine landslide<\/h5>\n

The press release reports on as yet unpublished research that investigated the tsunami using wave buoy data and modelling, demonstrating that the wave cannot be explained by the earthquake alone.\u00a0 This suggests a secondary source – most likely a submarine landslide – the potential location of which they tracked down using the wave buoy data.\u00a0 Dave Tappin of the BGS explains:<\/p>\n

‘Using maps of the seabed [I assume this means sonar data], we identified a landslide that was 40 kilometres wide, 20 kilometres long and 2 kilometres thick. That makes it 500 cubic kilometres, so it’s pretty big.’<\/p>\n

‘We then used computer models to simulate the tsunami from a dual source; the earthquake and the landslide, and this gave us the high water levels along the north Honshu coast.’<\/p>\n

‘An additional check on the landslide source was from an analysis of the wave frequency at the buoys, which showed a high-frequency component that could only be from the landslide.’<\/p><\/blockquote>\n

This is of course an enormous landslide – the volume is impressive in itself, but a slide with a thickness of two kilometres is genuinely amazing.\u00a0 I am really looking forward to seeing the submarine imagery of this event.\u00a0 The Tohoku earthquake and tsunami<\/a> killed about 16,000 people and left about 2,700 missing.<\/p>\n","protected":false},"excerpt":{"rendered":"

A NERC press release today suggests that the tsunami triggered by the 2011 Tohoku earthquake was exacerbated by a 500 cubic kilometre submarine landslide<\/p>\n","protected":false},"author":22,"featured_media":7482,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[537],"tags":[23,361,129,757,756],"class_list":["post-7479","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-earthquake-induced-landslide","tag-earthquake","tag-japan","tag-submarine-landslide","tag-tohoku","tag-tsumani"],"_links":{"self":[{"href":"https:\/\/blogs.agu.org\/landslideblog\/wp-json\/wp\/v2\/posts\/7479","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=7479"}],"version-history":[{"count":0,"href":"https:\/\/blogs.agu.org\/landslideblog\/wp-json\/wp\/v2\/posts\/7479\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/blogs.agu.org\/landslideblog\/wp-json\/wp\/v2\/media\/7482"}],"wp:attachment":[{"href":"https:\/\/blogs.agu.org\/landslideblog\/wp-json\/wp\/v2\/media?parent=7479"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/blogs.agu.org\/landslideblog\/wp-json\/wp\/v2\/categories?post=7479"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/blogs.agu.org\/landslideblog\/wp-json\/wp\/v2\/tags?post=7479"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}