{"id":30380,"date":"2019-03-11T07:27:22","date_gmt":"2019-03-11T07:27:22","guid":{"rendered":"https:\/\/blogs.agu.org\/landslideblog\/?p=30380"},"modified":"2019-03-11T08:54:03","modified_gmt":"2019-03-11T08:54:03","slug":"uttarakhand-1","status":"publish","type":"post","link":"https:\/\/blogs.agu.org\/landslideblog\/2019\/03\/11\/uttarakhand-1\/","title":{"rendered":"A  video of a small but spectacular rockslide from Uttarakhand"},"content":{"rendered":"<h4>A video of a small but spectacular rockslide from Uttarakhand<\/h4>\n<p><a href=\"https:\/\/www.youtube.com\/watch?v=1NL_1enbuv4\">A video has been posted onto Youtube<\/a> showing a reasonably small but undeniably spectacular rockslide:-<\/p>\n<iframe loading=\"lazy\" width=\"480\" height=\"360\" src=\"https:\/\/www.youtube.com\/embed\/1NL_1enbuv4?feature=oembed\" frameborder=\"0\" allow=\"accelerometer; autoplay; encrypted-media; gyroscope; picture-in-picture\" allowfullscreen><\/iframe>\n<p>.<\/p>\n<p>In the comments section the location is described as being Uttarakhand, but no further details are provided.\u00a0 [Update &#8211; <a href=\"https:\/\/twitter.com\/Indian_Rivers\/status\/1105026693163634688\">in a tweet SANDRP reports<\/a> that the location is Bhatwadi in Uttarkashi district, and that the landslide happened last year] This appears to be to be as good an example as one could wish to find of a rockslide caused by discontinuities (joints) aligned with the slope &#8211; take a look at this still from the start of the video:-<\/p>\n<div id=\"attachment_30382\" style=\"width: 418px\" class=\"wp-caption aligncenter\"><img loading=\"lazy\" decoding=\"async\" aria-describedby=\"caption-attachment-30382\" class=\"size-full wp-image-30382\" src=\"https:\/\/blogs.agu.org\/landslideblog\/files\/2019\/03\/19_03-rockslide-1.jpg\" alt=\"Uttarakhand\" width=\"408\" height=\"451\" srcset=\"https:\/\/blogs.agu.org\/landslideblog\/files\/2019\/03\/19_03-rockslide-1.jpg 408w, https:\/\/blogs.agu.org\/landslideblog\/files\/2019\/03\/19_03-rockslide-1-271x300.jpg 271w\" sizes=\"auto, (max-width: 408px) 100vw, 408px\" \/><p id=\"caption-attachment-30382\" class=\"wp-caption-text\">The rock slope in Uttarakhand prior to the failure. Still from a video <a href=\"https:\/\/www.youtube.com\/watch?v=1NL_1enbuv4\">posted on Youtube by Sanjay Bisht<\/a>.<\/p><\/div>\n<p>.<\/p>\n<p>The plane of weakness on which sliding occurred can be clearly seen. It appears that in constructing the road the toe of the landslide has been removed, leaving the rock blocks free to slide on that surface.\u00a0 Failure then occurs sequentially, with further failure of blocks at the toe of the slide destabilising the main rock mass.\u00a0 When sliding initiates the blocks move along this surface until free to fall:-<\/p>\n<div id=\"attachment_30385\" style=\"width: 421px\" class=\"wp-caption aligncenter\"><img loading=\"lazy\" decoding=\"async\" aria-describedby=\"caption-attachment-30385\" class=\"size-full wp-image-30385\" src=\"https:\/\/blogs.agu.org\/landslideblog\/files\/2019\/03\/19_03-rockslide-2.jpg\" alt=\"Uttarakhand\" width=\"411\" height=\"473\" srcset=\"https:\/\/blogs.agu.org\/landslideblog\/files\/2019\/03\/19_03-rockslide-2.jpg 411w, https:\/\/blogs.agu.org\/landslideblog\/files\/2019\/03\/19_03-rockslide-2-261x300.jpg 261w\" sizes=\"auto, (max-width: 411px) 100vw, 411px\" \/><p id=\"caption-attachment-30385\" class=\"wp-caption-text\">The rock slope in Uttarakhand as the the failure develops. Still from a video posted on <a href=\"https:\/\/www.youtube.com\/watch?v=1NL_1enbuv4\">Youtube by Sanjay Bisht<\/a>.<\/p><\/div>\n<p>.<\/p>\n<p>Once free, the mass rapidly fragments, although some large blocks remain intact:-<\/p>\n<div id=\"attachment_30387\" style=\"width: 418px\" class=\"wp-caption aligncenter\"><img loading=\"lazy\" decoding=\"async\" aria-describedby=\"caption-attachment-30387\" class=\"size-full wp-image-30387\" src=\"https:\/\/blogs.agu.org\/landslideblog\/files\/2019\/03\/19_03-rockslide-3.jpg\" alt=\"Uttarakhand\" width=\"408\" height=\"497\" srcset=\"https:\/\/blogs.agu.org\/landslideblog\/files\/2019\/03\/19_03-rockslide-3.jpg 408w, https:\/\/blogs.agu.org\/landslideblog\/files\/2019\/03\/19_03-rockslide-3-246x300.jpg 246w\" sizes=\"auto, (max-width: 408px) 100vw, 408px\" \/><p id=\"caption-attachment-30387\" class=\"wp-caption-text\">Full failure of the rock slope in Uttarakhand. Still from a video posted on <a href=\"https:\/\/www.youtube.com\/watch?v=1NL_1enbuv4\">Youtube by Sanjay Bisht<\/a>.<\/p><\/div>\n<p>.<\/p>\n<p>This is a fine example of the <a href=\"https:\/\/blogs.agu.org\/landslideblog\/2017\/03\/29\/nepal-rural-roads-1\/\">need to ensure that rock slopes are properly assessed<\/a> and, where appropriate, engineered to prevent failure.\u00a0 The need for a proper engineering approach has been described in detail over the last 30 years by <a href=\"http:\/\/hearngeoserve.co.uk\/index.html\">Dr Gareth Hearn<\/a>.\u00a0 He has a good <a href=\"https:\/\/www.google.com\/url?sa=t&amp;rct=j&amp;q=&amp;esrc=s&amp;source=web&amp;cd=5&amp;ved=2ahUKEwjI6d6sw_ngAhVuQhUIHRCpBwMQFjAEegQIVxAC&amp;url=https%3A%2F%2Fwww.geolsoc.org.uk%2F~%2Fmedia%2Fshared%2Fdocuments%2FEvents%2FPast%2520Meeting%2520Resources%2FHimalaya%252014%2520Hearn%2520Engineering%2520challenges.pdf&amp;usg=AOvVaw1ettoA1meGigdNT9YB7VaR\">presentation summarising the key issues<\/a> (NB PDF). The techniques for preventing this type of failure are well established and comparatively simple to implement, but in many mountain areas a combination of a lack of resource and a lack of expertise mean that this does not happen. The upshot is increased disruption, high levels of hazard and, when the slope fails, substantial environmental cost.<\/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 video has been posted onto Youtube showing a reasonably small but undeniably spectacular rockslide in Uttarakhand in the Indian Himalayas <!-- 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":30387,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[29],"tags":[1705,469,5,27,136,72],"class_list":["post-30380","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-landslide-video","tag-engineering","tag-featured","tag-india","tag-road","tag-rockslide","tag-south-asia"],"_links":{"self":[{"href":"https:\/\/blogs.agu.org\/landslideblog\/wp-json\/wp\/v2\/posts\/30380","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=30380"}],"version-history":[{"count":0,"href":"https:\/\/blogs.agu.org\/landslideblog\/wp-json\/wp\/v2\/posts\/30380\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/blogs.agu.org\/landslideblog\/wp-json\/wp\/v2\/media\/30387"}],"wp:attachment":[{"href":"https:\/\/blogs.agu.org\/landslideblog\/wp-json\/wp\/v2\/media?parent=30380"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/blogs.agu.org\/landslideblog\/wp-json\/wp\/v2\/categories?post=30380"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/blogs.agu.org\/landslideblog\/wp-json\/wp\/v2\/tags?post=30380"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}