{"id":31832,"date":"2019-08-05T06:15:03","date_gmt":"2019-08-05T06:15:03","guid":{"rendered":"https:\/\/blogs.agu.org\/landslideblog\/?p=31832"},"modified":"2019-08-05T06:15:03","modified_gmt":"2019-08-05T06:15:03","slug":"grandview-surf-beach-1","status":"publish","type":"post","link":"https:\/\/blogs.agu.org\/landslideblog\/2019\/08\/05\/grandview-surf-beach-1\/","title":{"rendered":"Grandview Surf Beach: a fatal rock topple in California"},"content":{"rendered":"

Grandview Surf Beach: a fatal rock topple in California<\/h4>\n

On Friday a small rock topple occurred on sandstone bluffs on Grandview Surf Beach in Encinitas to the north of San Diego, in California, USA.\u00a0 The topple<\/a> appears to have occurred without identified precursors<\/a>.\u00a0 Three people were tragically killed in this landslide.\u00a0 This image, from Channel News Asia<\/a>, provides an overview of the event:-<\/p>\n

\"Grandview

The rock topple at Grandview Surf Beach in California on 2nd August 2019. Image via Channel News Asia<\/a>.<\/p><\/div>\n

.<\/p>\n

Reports indicate<\/a> that the three victims were all women from the same family, who were local to the area.<\/p>\n

The images above suggest that the failure mechanisms on these cliffs are quite complex, with rock toppling on the steep lower parts of the bluffs and shallow slips on the slightly lower angled upper sections.\u00a0 In this case the landslide appears to have been primarily the result of a large (some reports suggest about 10 m long) slab that underwent a toppling failure.\u00a0 Some of the debris from the upper part of the slope might also have been incorporated.\u00a0 This image, from Flipboard<\/a>, gives a better sense of this failure event:-<\/p>\n

\"Grandview

Overview of the aftermath of the rock topple at Grandview Surf Beach on 2nd August 2019. Image via Flipboard<\/a>.<\/p><\/div>\n

.<\/p>\n

The images above both suggest that the sea erodes a notch at the foot of the cliff at this site (such a notch can be seen on the left side of the image above), destabilising the face of the cliff.\u00a0 This sets up a classic toppling scenario.\u00a0 Note that the sandstones that form this cliff have little jointing, a situation that allows larger slabs to form and that sets up failures that can be rapid and catastrophic.<\/p>\n

Coastal cliffs can be dangerous<\/a>.\u00a0 There often seems to be a presumption that rockfalls occur primarily in periods of poor weather.\u00a0 I am not sure that there is much evidence to support that assumption.<\/p>\n","protected":false},"excerpt":{"rendered":"

On 2nd August 2019 a rock topple on Grandview Surf Beach near San Diego in California killed three women from a single family<\/p>\n","protected":false},"author":22,"featured_media":31839,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[739],"tags":[137,732,469,725,540,48],"class_list":["post-31832","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-coast-2","tag-california","tag-coastal-cliff","tag-featured","tag-north-america","tag-topple","tag-usa"],"_links":{"self":[{"href":"https:\/\/blogs.agu.org\/landslideblog\/wp-json\/wp\/v2\/posts\/31832","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=31832"}],"version-history":[{"count":0,"href":"https:\/\/blogs.agu.org\/landslideblog\/wp-json\/wp\/v2\/posts\/31832\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/blogs.agu.org\/landslideblog\/wp-json\/wp\/v2\/media\/31839"}],"wp:attachment":[{"href":"https:\/\/blogs.agu.org\/landslideblog\/wp-json\/wp\/v2\/media?parent=31832"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/blogs.agu.org\/landslideblog\/wp-json\/wp\/v2\/categories?post=31832"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/blogs.agu.org\/landslideblog\/wp-json\/wp\/v2\/tags?post=31832"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}