{"id":17473,"date":"2016-01-20T08:21:34","date_gmt":"2016-01-20T08:21:34","guid":{"rendered":"http:\/\/blogs.agu.org\/landslideblog\/?p=17473"},"modified":"2016-01-20T08:21:34","modified_gmt":"2016-01-20T08:21:34","slug":"las-cortederas-landslide","status":"publish","type":"post","link":"https:\/\/blogs.agu.org\/landslideblog\/2016\/01\/20\/las-cortederas-landslide\/","title":{"rendered":"Landslides in Chile Part 2: Las Cortaderas"},"content":{"rendered":"
Landslides in Chile Part 2: Las Cortaderas Landslide<\/h5>\n

Located not far from Santiago, in the upper reaches of the Maipo River catchment, is a very large mass movement, known as the Las Cortaderas Landslide.\u00a0 This is a fascinating landslide, not least because there are two distinct phases.\u00a0 The main landslide is vast – an ancient rock avalanche that entered the valley at some point in the past (of which more below).\u00a0 The frontal portion of this landslide deposit then failed again in the 1958 Las Melosas earthquake, blocking the Yeso River.\u00a0 This makes the later landslide sound like a small event – it is certainly not.\u00a0 Sepulveda et al.<\/em> (2008)<\/a> estimated that it had a volume of 15 to 20 million cubic metres, which is a large landslide by any standard. \u00a0 The river was blocked for a few years before breaching naturally.\u00a0 This is a view of the landslide from upstream:<\/p>\n

\"La<\/a>

Las Cortaderas Landslide from upstream<\/p><\/div>\n

.<\/p>\n

To illustrate the features of the lower part of the landslide, I have annotated the photograph below:<\/p>\n

\"La<\/a>

Annotated image of the Las Cortaderas Landslide<\/p><\/div>\n

.<\/p>\n

This image shows the landslide scar with the deposit on the right hand side (the scar is just to the left of the power cables):<\/p>\n

\"The<\/a>

Las Cortaderas Landslide<\/p><\/div>\n

.<\/p>\n

But, as mentioned above, the 1958 La Cortaderas landslide is a comparatively small failure of the deposit of a much larger landslide body.\u00a0 This is the Google Earth image of the site – I have annotated the 1958 landslide and the larger rock avalanche deposit from which it originated:-<\/p>\n

\"La<\/a>

Las Cortaderas Landslide via Google Earth<\/p><\/div>\n

.<\/p>\n

Taking a wider view though, the scale of the ancient rock avalanche becomes clear:<\/p>\n

\"Las<\/a>

Las Cortaderas Landslide<\/p><\/div>\n

.<\/p>\n

This is a truly huge landslide that would have blocked the river before breaching.\u00a0 The current river cuts through the landslide deposit, leaving a portion of the deposit on the other side of the valley.\u00a0 This is clearly exposed by the river.\u00a0 Note the chaotic landslide deposit, with the predominance of the largest boulders occurring in the upper portions:-<\/p>\n

\"La<\/a>

Las Cortaderas Landslide deposit<\/p><\/div>\n

.<\/p>\n

But if you think this is large, you should see what lies upstream – of which more tomorrow.<\/p>\n","protected":false},"excerpt":{"rendered":"

High in the Andes in central Chile lies the Las Cortaderas Landslide complex, the most recent portion of which was triggered by an earthquake in 1958<\/p>\n","protected":false},"author":22,"featured_media":17482,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[69],"tags":[1046,23,469,306,122],"class_list":["post-17473","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-landslide-images","tag-chile","tag-earthquake","tag-featured","tag-rock-avalanche","tag-south-america"],"_links":{"self":[{"href":"https:\/\/blogs.agu.org\/landslideblog\/wp-json\/wp\/v2\/posts\/17473","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=17473"}],"version-history":[{"count":0,"href":"https:\/\/blogs.agu.org\/landslideblog\/wp-json\/wp\/v2\/posts\/17473\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/blogs.agu.org\/landslideblog\/wp-json\/wp\/v2\/media\/17482"}],"wp:attachment":[{"href":"https:\/\/blogs.agu.org\/landslideblog\/wp-json\/wp\/v2\/media?parent=17473"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/blogs.agu.org\/landslideblog\/wp-json\/wp\/v2\/categories?post=17473"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/blogs.agu.org\/landslideblog\/wp-json\/wp\/v2\/tags?post=17473"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}