Tuesday, January 17, 2006

Landslide in Dorset

On 14th January 2006 a landslide occurred near Charmouth in West Dorset and 17 people had to be rescued from rising tides due to the landslide debris. The landslide has destroyed more of the coastal path and new cracks have opened up in the fields above, indicating further activity is to come. The area is prone to landsliding because impermeable Jurassic clays and limestones underly permeable Cretaceous Greensand. Following prolonged rainfall, the accumulation of percolated water at the boundary between the two formations causes seepage, lubrication and a consequent loss of friction. The result is that the upper strata slide over the underlying strata.

For more information on the geology and landsliding along this stretch of coast, visit the Jurassic Coast web site