{"id":26670,"date":"2018-02-02T08:30:41","date_gmt":"2018-02-02T08:30:41","guid":{"rendered":"https:\/\/blogs.agu.org\/landslideblog\/?p=26670"},"modified":"2018-02-02T15:18:48","modified_gmt":"2018-02-02T15:18:48","slug":"maipo-valley-1","status":"publish","type":"post","link":"https:\/\/blogs.agu.org\/landslideblog\/2018\/02\/02\/maipo-valley-1\/","title":{"rendered":"Landslides in the Maipo Valley, Chile"},"content":{"rendered":"

Landslides in the Maipo Valley, Chile<\/h4>\n

Last month I was in Chile working with colleagues from the Universidad de Chile<\/a> and Universidad O’Higgins<\/a> on our Newton-Picarte Fund project<\/a> looking at seismically-triggered landslides<\/a> in the vicinity of Santiago.\u00a0 We were lucky enough to spend a couple of days in the Maipo Valley in the Andes, which is home to the most extraordinary collection of very large landslides.\u00a0 The image below shows a Google Earth view of the area. As the image shows, this is a region of fascinating but complex geology, high relief and, of course, a variety of landslide types.<\/p>\n

\"Maipo\"

Google Earth image of the upper part of the Maipo Valley<\/p><\/div>\n

.<\/p>\n

In the southwest corner of the image above a large landslide can be seen.\u00a0 This is a very active earthflow that is the result of mobilisation of an area of intensively hydrothermally-altered rocks.\u00a0 The upshot is a very spectacular, very active flow:-<\/p>\n

\"Maipo

A large earthflow in hydrothermally-altered rocks in Chile<\/p><\/div>\n

.<\/p>\n

However, most of the landslides in this valley are rockslope failures.\u00a0 As the image below shows this is a landscape that is dominated by landslide processes:-<\/p>\n

\"Maipo

A landscape dominated by landslide processes in the Maipo Valley.<\/p><\/div>\n

.<\/p>\n

In many areas the landslides are controlled by structural weaknesses in the bedrock.\u00a0 The area shown below is one of the best examples that I have ever seen.\u00a0 The massif in the background has a series of planar surfaces that mark previous rockslide events.\u00a0 Note the dispirate orientations and slope angles.\u00a0 This is a beautiful example of the ways in which local planes of weakness can dominate slope behaviour.\u00a0 These are hoever very large in scale ( hundreds of metres in length and width.<\/p>\n

\"Maipo

Multiple failure planes in bedrock massifs.<\/p><\/div>\n

.<\/p>\n

The image below shows two of these surfaces, which have generated a very large translational rockslide.\u00a0 Analysis suggests that it is likely that this rockslide was triggered by an earthquake:-<\/p>\n

\"Maipo

Planar failure surfaces in the Maipo Valley, Chile.<\/p><\/div>\n

.<\/p>\n

As a result there are numerous rockslide deposits in the valley, such as the one shown below, providing evidence of past catastrophic rock avalanches:-<\/p>\n

\"Maipo

Large rockslide deposits in the Maipo Valley – note the cars for scale.<\/p><\/div>\n

.<\/p>\n

In places the boulders that form the deposits are vast.\u00a0 This is one such deposit – note the people in the bottom left of the image for scale.<\/p>\n

\"Maipo

Large rock slide deposits in the Maipo Valley.<\/p><\/div>\n

Acknowledgement<\/h4>\n

This project was funded by NERC via the Newton-Picarte Fund. Grant: NE\/N000315\/2:\u00a0 Seismically-induced landslides in Chile: New tools for hazard assessment and disaster prevention. <\/em>I appreciate their help and support.<\/p>\n","protected":false},"excerpt":{"rendered":"

As part of our Newton Fund project, I spent a few days in January looking at the giant landslides of the Maipo Valley in Chile. These are some of my photos of these amazing rockslides and rock avalanches<\/p>\n","protected":false},"author":22,"featured_media":26690,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[69],"tags":[1046,469,983,306,136,122],"class_list":["post-26670","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-landslide-images","tag-chile","tag-featured","tag-landslide-images","tag-rock-avalanche","tag-rockslide","tag-south-america"],"_links":{"self":[{"href":"https:\/\/blogs.agu.org\/landslideblog\/wp-json\/wp\/v2\/posts\/26670","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=26670"}],"version-history":[{"count":0,"href":"https:\/\/blogs.agu.org\/landslideblog\/wp-json\/wp\/v2\/posts\/26670\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/blogs.agu.org\/landslideblog\/wp-json\/wp\/v2\/media\/26690"}],"wp:attachment":[{"href":"https:\/\/blogs.agu.org\/landslideblog\/wp-json\/wp\/v2\/media?parent=26670"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/blogs.agu.org\/landslideblog\/wp-json\/wp\/v2\/categories?post=26670"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/blogs.agu.org\/landslideblog\/wp-json\/wp\/v2\/tags?post=26670"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}