Foula landslides





Shallow landslides, bog bursts and debris flows above Channerwick











Looking east to Channerwick from a source zone for the bog burst. Slope failure has extended through the peat and regolith to exposures the steeply-dipping surface of the quartzite and phyllite

Bog bursts

Significance: an example of how intense, localised rainfall can lead to extensive and potentially hazardous mass movement

The steep slopes above Channerwick are locally mantled by several metres of peat. On 19/9/2003 the area experienced rainfall from one or two small but intense and stationary convection cells. Rainfall intensity probably reached more then 40 mm/hr and led to saturation of bogs and eventually bursts and associated shallow landslides in a number of areas. The worst affected area was perhaps the Burn of Channerwick where the A970 was cut in a 200 m section. A related debris flow removed a large part of the beach at Hoswick.