{"id":33018,"date":"2020-02-11T07:39:47","date_gmt":"2020-02-11T07:39:47","guid":{"rendered":"https:\/\/blogs.agu.org\/landslideblog\/?p=33018"},"modified":"2020-02-11T07:39:47","modified_gmt":"2020-02-11T07:39:47","slug":"shuicheng-landslide-1","status":"publish","type":"post","link":"https:\/\/blogs.agu.org\/landslideblog\/2020\/02\/11\/shuicheng-landslide-1\/","title":{"rendered":"A seismic analysis of the 23 July 2019 Shuicheng landslide in China"},"content":{"rendered":"<h4>A seismic analysis of the 23 July 2019 Shuicheng landslide in China<\/h4>\n<p>On 23 July 2019 a large landslide occurred at Pingdi in Shuicheng County in western Guizhou Province, China, killing 51 people. <a href=\"https:\/\/blogs.agu.org\/landslideblog\/2019\/07\/25\/pingdi-landslide\/\">I covered this large landslide, one of the more significant of 2019, at the time<\/a>, and in August 2019 <a href=\"https:\/\/blogs.agu.org\/landslideblog\/2019\/08\/20\/pingdi-landslide-2\/\">I posted<\/a> the following high-resolution <a href=\"https:\/\/www.planet.com\/\">Planet Labs image<\/a> of the slide:-<\/p>\n<div id=\"attachment_31939\" style=\"width: 650px\" class=\"wp-caption aligncenter\"><img loading=\"lazy\" decoding=\"async\" aria-describedby=\"caption-attachment-31939\" class=\"wp-image-31939 size-full\" src=\"https:\/\/blogs.agu.org\/landslideblog\/files\/2019\/08\/19_08-China-1-e1566267464744.jpg\" alt=\"Shuicheng landslide\" width=\"640\" height=\"562\" \/><p id=\"caption-attachment-31939\" class=\"wp-caption-text\">A <a href=\"https:\/\/www.planet.com\/\">Planet Labs<\/a> SkySat image of the Shuicheng landslide in Guizhou Province China. Image collected on 2nd August 2019, copyright <a href=\"https:\/\/www.planet.com\/\">Planet Lab<\/a>s, used with permission.<\/p><\/div>\n<p>.<\/p>\n<p>A first analysis of the Shuicheng landslide (<a href=\"https:\/\/link.springer.com\/article\/10.1007\/s10346-020-01358-x\">Yan <em>et al.<\/em> 2020<\/a>) has now been published in the journal <em><a href=\"https:\/\/link.springer.com\/journal\/10346\">Landslides<\/a><\/em>. The most interesting element of this piece of work is that it uses a very detailed analysis of the seismic signals generated by the landslide to interpret its behaviour.\u00a0 This is one of the most detailed analyses of this type to date.\u00a0 It is particularly intriguing because of the behaviour of the slide, which I highlighted at the time, with an initial planar sliding component (in the vicinity of the road at the top of the slope, which is the bottom of the image above), bifurcation into two components in the middle part of the track, and then a single runout zone. Interestingly, <a href=\"https:\/\/link.springer.com\/article\/10.1007\/s10346-020-01358-x\">Yan <em>et al.<\/em> (2020<\/a>) have been able to back-analyse this behaviour from the seismic data.<\/p>\n<p>As a consequence of this investigation, the authors have provided this schematic of the behaviour of the Shiucheng landslide:-<\/p>\n<div id=\"attachment_33021\" style=\"width: 525px\" class=\"wp-caption aligncenter\"><img loading=\"lazy\" decoding=\"async\" aria-describedby=\"caption-attachment-33021\" class=\"wp-image-33021\" src=\"https:\/\/blogs.agu.org\/landslideblog\/files\/2020\/02\/20_02-Shiucheng-1.jpg\" alt=\"Shuicheng landslide\" width=\"515\" height=\"712\" srcset=\"https:\/\/blogs.agu.org\/landslideblog\/files\/2020\/02\/20_02-Shiucheng-1.jpg 684w, https:\/\/blogs.agu.org\/landslideblog\/files\/2020\/02\/20_02-Shiucheng-1-217x300.jpg 217w\" sizes=\"auto, (max-width: 515px) 100vw, 515px\" \/><p id=\"caption-attachment-33021\" class=\"wp-caption-text\">Schematic diagram showing the behaviour of the Shuicheng landslide, as interpreted from the seismic data by <a href=\"https:\/\/link.springer.com\/article\/10.1007\/s10346-020-01358-x\">Yan <em>et al.<\/em> (2020)<\/a>.<\/p><\/div>\n<p>.<\/p>\n<p>To my surprise, the data suggests that the Shuicheng landslide started below the road (Road A), not on the upslope side. <a href=\"https:\/\/link.springer.com\/article\/10.1007\/s10346-020-01358-x\">Yan et al. (2020)<\/a> suggest that this might have been the result of saturation of this part of the slope due to runoff from the road.\u00a0 This initial landslide was small, but it soon destabilised a wider area, such that a larger mass in the crown of the landslide began to move. Failure of this upper portion of the slope remained slow, but as the mass loaded the steeper slope below, the landslide both accelerated and increased in volume as material was entrained.<\/p>\n<p>In the third stage of the Shuicheng landslide, the natural topography forced it to bifurcate into the two portions seen in the satellite image.\u00a0 The landslide was now rapid and was efficient in entraining debris.<\/p>\n<p>Finally, the mass reached the bottom of the slope and was deposited in the valley.\u00a0 The seismic data indicates a rapid deceleration once the topography no longer supported sliding.<\/p>\n<p><a href=\"https:\/\/blogs.agu.org\/landslideblog\/2019\/08\/20\/pingdi-landslide-2\/\">In my original posts I hypothesised that the road had destabilised the slope<\/a>, but my interpretation was that it would have been the section upslope of the road that failed first. <a href=\"https:\/\/link.springer.com\/article\/10.1007\/s10346-020-01358-x\">Yan <em>et al.<\/em> (2020)<\/a>, using quantitative data, have shown that whilst the road was indeed a key factor, it was the downhill portion that failed first.<\/p>\n<p>This is a really nice example of the ways in which these new quantitative datasets can provide insight into landslide mechanisms.<\/p>\n<h4>Reference and acknowledgement<\/h4>\n<p>Yan, Y., Cui, Y., Tian, X. <em>et al.<\/em> 2020. <a href=\"https:\/\/link.springer.com\/article\/10.1007\/s10346-020-01358-x\">Seismic signal recognition and interpretation of the 2019 \u201c7.23\u201d Shuicheng landslide by seismogram stations<\/a>. <em>Landslides.<\/em>\u00a0 https:\/\/doi.org\/10.1007\/s10346-020-01358-x<\/p>\n<p>Planet Team (2020). Planet Application Program Interface: In Space for Life on Earth. San Francisco, CA. <a href=\"https:\/\/www.planet.com\/\">https:\/\/www.planet.com\/<\/a><\/p>\n<!-- AddThis Advanced Settings generic via filter on the_content --><!-- AddThis Share Buttons generic via filter on the_content -->","protected":false},"excerpt":{"rendered":"<p>A seismic analysis of the 23 July 2019 Shuicheng landslide in China, which killed 51 people, has provided a detailed understanding of the failure process<!-- AddThis Advanced Settings generic via filter on wp_trim_excerpt --><!-- AddThis Share Buttons generic via filter on wp_trim_excerpt --><\/p>\n","protected":false},"author":22,"featured_media":33021,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[608,544],"tags":[16,881,469,192,17,25,588],"class_list":["post-33018","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-research-project","category-review-of-a-paper","tag-china","tag-east-asia","tag-featured","tag-paper","tag-research","tag-satellite","tag-seismic"],"_links":{"self":[{"href":"https:\/\/blogs.agu.org\/landslideblog\/wp-json\/wp\/v2\/posts\/33018","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=33018"}],"version-history":[{"count":0,"href":"https:\/\/blogs.agu.org\/landslideblog\/wp-json\/wp\/v2\/posts\/33018\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/blogs.agu.org\/landslideblog\/wp-json\/wp\/v2\/media\/33021"}],"wp:attachment":[{"href":"https:\/\/blogs.agu.org\/landslideblog\/wp-json\/wp\/v2\/media?parent=33018"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/blogs.agu.org\/landslideblog\/wp-json\/wp\/v2\/categories?post=33018"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/blogs.agu.org\/landslideblog\/wp-json\/wp\/v2\/tags?post=33018"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}