Failure and flow on a 35° slope: Causes and three-dimensional observations

✍ Scribed by Julian A. Dowdeswell; Henry F. Lamb; John Lewin

• Publisher: John Wiley and Sons
• Year: 1988
• Tongue: English
• Weight: 995 KB
• Volume: 13
• Category: Article
• ISSN: 0360-1269
• DOI: 10.1002/esp.3290130808

✦ Synopsis

A well-vegetated 35" slope in upland Wales, U.K., failed during a winter flood event. Failure was linked to high magnitude rainfall and diversion of flowing water onto the slope. Mass movement began with gravitational slumping, which was transformed rapidly into a debris flow. Three-dimensional characteristics of the active debris flow are reconstructed from mudlines on 58 trees still standing in the flow path. Mudline formation only on the up-flow side of trees indicates the relatively high viscosity of the debris flow. Mudline height is a function of the maximum thickness and velocity of the flow at any tree.