{"id":40310,"date":"2022-02-25T08:32:02","date_gmt":"2022-02-25T08:32:02","guid":{"rendered":"https:\/\/blogs.agu.org\/landslideblog\/?p=40310"},"modified":"2022-02-25T10:28:00","modified_gmt":"2022-02-25T10:28:00","slug":"lyneham-1","status":"publish","type":"post","link":"https:\/\/blogs.agu.org\/landslideblog\/2022\/02\/25\/lyneham-1\/","title":{"rendered":"Lyneham – an interesting landslide from the south of England"},"content":{"rendered":"

Lyneham – an interesting landslide from the south of England<\/h4>\n

Yesterday the BBC reported on another serious landslide<\/a> triggered by the heavy rainfall that fell across the UK last week<\/a>.\u00a0 This landslide has caused very significant damage to the B6049 road near to the village of Lyneham in<\/a> Wiltshire.\u00a0 The location is 51.517, -1.991.\u00a0 The BBC has this image of the aftermath of the landslide:-<\/p>\n

\"Damage

Landslide damage to the B4069 in Lyneham, Wiltshire. Image from the BBC.<\/em><\/p><\/div>\n

.<\/p>\n

It is clear that there has been very substantial vertical movement on the slope.\u00a0 Interestingly, a Google StreetView image of the road<\/a> suggests that it was undergoing considerable distress back in October 2021:-<\/p>\n

\"Google

Google StreetView<\/a> of a section of the B6049 near to Lyneham, showing extensive cracking in the road.<\/em><\/p><\/div>\n

.<\/p>\n

This crack appears to indicate extension, which is consistent with the deformation observed in the failure last week.<\/p>\n

Google Earth has good imagery of the site.\u00a0 This image was collected in April 2021:-<\/p>\n

\"Google

Google Earth image of the site of the landslide at Lyneham in southern England. Note the relict solifluction feature in the field downslope of the road<\/em>.<\/p><\/div>\n

.<\/p>\n

In the field downslope of the road (nearer to the camera) there is a clear large, shallow landslide lobe.\u00a0 There is a further lobe to the right of the image, emerging from the same morphological feature.\u00a0 I would interpret this as probable ancient solifluction landslide<\/a> – an active layer detachment – left over from the period when this area was affected by permafrost conditions during Pleistocene “Ice Age”.\u00a0 These features are common in southern Britain<\/a>. Note also that upslope of the road there appear to be some features that could be tension cracks in the field.<\/p>\n

There are similar lobes in some of the other fields too.<\/p>\n

So the most likely explanation for the landslide near to Lyneham is that it is a reactivation of a pre-existing failure, probably a solifluction landslide, caused by the exceptional rainfall that we are now experiencing.\u00a0 Of course a detailed site investigation is needed to verify this initial hypothesis.<\/p>\n

It will also be interesting to find out whether this is simply the results of increased rainfall or whether some other change has occurred in the area, such as a modification to the drainage. Are there signs of some construction activity in the field in the top left corner, for example?\u00a0 Without a detailed investigation it is impossible to know if this could have been a factor.<\/p>\n","protected":false},"excerpt":{"rendered":"

Last week, a landslide disrupted the B4069 road at Lyneham in S. England. Initial analysis suggests this could be the reactivation of an ancient solifluction failure. <\/p>\n","protected":false},"author":22,"featured_media":40313,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[3],"tags":[182,144,469,959,30679,30678,133],"class_list":["post-40310","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-landslide-report","tag-england","tag-europe","tag-featured","tag-landslide-report","tag-periglacial","tag-solifluction","tag-uk"],"_links":{"self":[{"href":"https:\/\/blogs.agu.org\/landslideblog\/wp-json\/wp\/v2\/posts\/40310","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=40310"}],"version-history":[{"count":0,"href":"https:\/\/blogs.agu.org\/landslideblog\/wp-json\/wp\/v2\/posts\/40310\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/blogs.agu.org\/landslideblog\/wp-json\/wp\/v2\/media\/40313"}],"wp:attachment":[{"href":"https:\/\/blogs.agu.org\/landslideblog\/wp-json\/wp\/v2\/media?parent=40310"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/blogs.agu.org\/landslideblog\/wp-json\/wp\/v2\/categories?post=40310"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/blogs.agu.org\/landslideblog\/wp-json\/wp\/v2\/tags?post=40310"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}