Intermittent surging movements of a coastal landslide
- 1 November 1987
- journal article
- Published by Wiley in Earth Surface Processes and Landforms
- Vol. 12 (6) , 597-603
- https://doi.org/10.1002/esp.3290120603
Abstract
Since the late 1960s there has been a large mudslide in coastal cliffs of Permo‐Triassic strata (conglomerate overlying mudstone) at West Down Beacon, 2 km west of Budleigh Salterton, Devon. A total displacement of 100 m was achieved between 1981 and 1985 as the lobate toe of the mudslide pushed forward across the beach in eleven surges of movement. Each surge involved a displacement of between 5 and 15 m and was completed within a few hours. The toe moved by planar sliding, possibly on more than one seaward‐dipping shear surface or zone. Occasionally there were additional relatively minor displacements (less than 1 m), but normally the mudslide was stationary between the major surges. After each surge high‐oblique aerial photographs were obtained for stereoscopic interpretation. Debris falls from the cliff appear to have triggered some of the mudslide surges. A displacement recording of one surge has indicated that the rate of movement of the mudslide may have been partly controlled by variations in sea level during the tidal cycle.Keywords
This publication has 3 references indexed in Scilit:
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