15 March 2018

Llusco, Peru: a dramatic landslide has destroyed 100 houses

Posted by Dave Petley

Llusco, Peru: a dramatic landslide has destroyed 100 houses

A major landslide at Llusco in the Cusco region of Peru over the last few days has led to the destruction of over 100 houses, and the declaration of a state of emergency by the government.  The local authorities have stated that the landslide was caused by high pore water pressures, rather than by seismic activity. The landslide is reported to cover an area of about 30 hectares.  The best images that I have seen of the landslide reside in a Youtube video that was shot by a drone by Fameco Films and Art.  This should be visible below:-

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Based on this video the landslide appears to be a very large slump, with movement of a very large block.  However, the shear surface is, I suspect, non-circular, which has caused the block to fracture extensively.  This can be seen in the image below, taken from the video:-

Llusco landslide

Extensive fracturing in the displaced mass at Llusco in Peru. Image from a drone video posted to Youtube by Fameco Films and Art.

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The toe portion of the landslide has suffered very extensive fracturing and deformation, with a large amount of extension of the mass:-

Llusco landslide

Deformation of the frontal portion of the displaced mass at Llusco in Peru. Image from a drone video posted to Youtube by Fameco Films and Art.

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Unsurprisingly this has caused very extensive damage to the houses, which are no longer habitable.  The size of the fractures between displaced blocks is quite remarkable:

Llusco landslide

Damaged houseson the landslide at Llusco in Peru. Note the size of the fractures that have opened between the displaced blocks.Image from a drone video posted to Youtube by Fameco Films and Art.

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In many ways this landslide feels quite similar to the Seafront landslide (often known as the Cow Slide), triggered by the Kaikoura earthquake in New Zealand.