{"id":32636,"date":"2019-12-05T07:41:59","date_gmt":"2019-12-05T07:41:59","guid":{"rendered":"https:\/\/blogs.agu.org\/landslideblog\/?p=32636"},"modified":"2019-12-05T14:15:37","modified_gmt":"2019-12-05T14:15:37","slug":"blackhawk-rock-avalanche","status":"publish","type":"post","link":"https:\/\/blogs.agu.org\/landslideblog\/2019\/12\/05\/blackhawk-rock-avalanche\/","title":{"rendered":"The Blackhawk rock avalanche &#8211; insights from imagery"},"content":{"rendered":"<h4>The Blackhawk rock avalanche &#8211; insights from imagery<\/h4>\n<p><a href=\"https:\/\/blogs.agu.org\/landslideblog\/2019\/11\/15\/the-blackhawk-landslide\/\">A couple of weeks ago I posted about the remarkable Blackhawk rock avalanche in the USA<\/a>.&nbsp; Since then my regular and highly valued correspondent who goes by the pseudonym funkenbeachin has been putting together some additional information to aid the interpretation of this very large landslide.&nbsp; I would like to highlight two really interesting and important things that he has done.&nbsp; The first is a really impressive and useful video, <a href=\"https:\/\/www.youtube.com\/watch?v=Nf44--InPo4\">posted to Youtube,<\/a> that combined the geological map of the site with <a href=\"https:\/\/en.wikipedia.org\/wiki\/Multispectral_image\">multispectral satellite data<\/a>.&nbsp; You should be able to view this below:-<\/p>\n<p><iframe loading=\"lazy\" src=\"https:\/\/www.youtube.com\/embed\/Nf44--InPo4\" width=\"800\" height=\"450\" frameborder=\"0\" allowfullscreen=\"allowfullscreen\"><span data-mce-type=\"bookmark\" style=\"display: inline-block; width: 0px; overflow: hidden; line-height: 0;\" class=\"mce_SELRES_start\">\ufeff<\/span><\/iframe><\/p>\n<p>.<\/p>\n<p>Note that this uses Sentinel data.&nbsp; The annotation on the <a href=\"https:\/\/www.youtube.com\/watch?v=Nf44--InPo4\">Youtube video page<\/a> provides information about the sources of information and the band combinations used.<\/p>\n<p>This is really interesting for a number of reasons.&nbsp; First, it illustrates really well the ways in which multispectral imagery can be used to provide insight into the geological processes in a complex location.&nbsp; The different geological materials provide different spectral responses when the satellite band combinations are changed.&nbsp; This means that it becomes possible to discriminate between different deposits that look similar under normal conditions, providing real insight into the evolution of the landslide.&nbsp; This band combination is a really good example:-<\/p>\n<div id=\"attachment_32641\" style=\"width: 654px\" class=\"wp-caption aligncenter\"><img loading=\"lazy\" decoding=\"async\" aria-describedby=\"caption-attachment-32641\" class=\"size-full wp-image-32641\" src=\"https:\/\/blogs.agu.org\/landslideblog\/files\/2019\/12\/19_12-Blackhawk-YT-1.jpg\" alt=\"Blackhawk rock avalanche\" width=\"644\" height=\"603\" srcset=\"https:\/\/blogs.agu.org\/landslideblog\/files\/2019\/12\/19_12-Blackhawk-YT-1.jpg 644w, https:\/\/blogs.agu.org\/landslideblog\/files\/2019\/12\/19_12-Blackhawk-YT-1-300x281.jpg 300w\" sizes=\"auto, (max-width: 644px) 100vw, 644px\" \/><p id=\"caption-attachment-32641\" class=\"wp-caption-text\">A multispectral image of the area around the Blackhawk landslide. Still from a <a href=\"https:\/\/www.youtube.com\/watch?v=Nf44--InPo4\">Youtube video by funkenbeachin<\/a>.&nbsp; Data from <a href=\"https:\/\/sentinel.esa.int\/web\/sentinel\/home\">ESA Sentinel<\/a>, collected on 28 June 2019.<\/p><\/div>\n<p>.<\/p>\n<p>There is fascinating geological complexity in this image, in the bedrock source area, the sediments on the plains below and the landslide deposit itself.<\/p>\n<p>The second is the insight that this analysis provides into the evolution of the landslide itself.&nbsp; The very linear lateral eastern margin of the Blackhawk rock avalanche deposits for example is really interesting.&nbsp; I would be really interested to receive comments about your interpretation of the imagery.<\/p>\n<p>Funkenbeachin has also annotated and enhanced the <a href=\"https:\/\/thesis.library.caltech.edu\/691\/\">digitased Shreeve geological map<\/a> of the Blackhawk rock avalanche to make it easy to understand:-<\/p>\n<div id=\"attachment_32643\" style=\"width: 714px\" class=\"wp-caption aligncenter\"><img loading=\"lazy\" decoding=\"async\" aria-describedby=\"caption-attachment-32643\" class=\"size-full wp-image-32643\" src=\"https:\/\/blogs.agu.org\/landslideblog\/files\/2019\/12\/19_12-Blackhawk-YT-2.jpg\" alt=\"Blackhawk rock avalanche\" width=\"704\" height=\"888\" srcset=\"https:\/\/blogs.agu.org\/landslideblog\/files\/2019\/12\/19_12-Blackhawk-YT-2.jpg 704w, https:\/\/blogs.agu.org\/landslideblog\/files\/2019\/12\/19_12-Blackhawk-YT-2-238x300.jpg 238w\" sizes=\"auto, (max-width: 704px) 100vw, 704px\" \/><p id=\"caption-attachment-32643\" class=\"wp-caption-text\">The digitised Shreeve geological map of the Blackhawk rock avalanche. Image created by funkenbeachin.<\/p><\/div>\n<p>.<\/p>\n<p>He has very kindly provided a PDF of the map with far higher resolution than the image above &#8211; if you would like a copy then please drop me a line via d.n.petley@sheffield.ac.uk<\/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>Regular correspondent funkenbeachin has used ESA Sentinel multispectral satellite data to facilitate analysis of the Blackhawk rock avalanche  <!-- 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":32641,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[69],"tags":[137,469,963,725,306,25,20063,48],"class_list":["post-32636","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-landslide-images","tag-california","tag-featured","tag-landslide-video","tag-north-america","tag-rock-avalanche","tag-satellite","tag-sentinel","tag-usa"],"_links":{"self":[{"href":"https:\/\/blogs.agu.org\/landslideblog\/wp-json\/wp\/v2\/posts\/32636","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=32636"}],"version-history":[{"count":0,"href":"https:\/\/blogs.agu.org\/landslideblog\/wp-json\/wp\/v2\/posts\/32636\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/blogs.agu.org\/landslideblog\/wp-json\/wp\/v2\/media\/32641"}],"wp:attachment":[{"href":"https:\/\/blogs.agu.org\/landslideblog\/wp-json\/wp\/v2\/media?parent=32636"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/blogs.agu.org\/landslideblog\/wp-json\/wp\/v2\/categories?post=32636"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/blogs.agu.org\/landslideblog\/wp-json\/wp\/v2\/tags?post=32636"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}