Movement, moisture and thermal conditions at a turf-banked solifluction lobe, Kluane Range, Yukon territory, Canada

A turf-banked solifluction lobe was instrumented for the continuous recording of surface and internal movement, thaw settlement, soil volumetric moisture content and thermal conditions during the spring and summer of 2002. Strain probe measurements showed that gelifluction occurred as a series of discrete and abrupt displacements near the thaw plane, followed by retrograde movement. Most gelifluction events took place when thaw rates were high and the soil was saturated almost to the surface, but rain was also capable of inducing gelifluction at depth. The rapid and localized character of the observed displacements suggests that gelifluction results from micro-shearing of the soil, possibly along the interface of thawing ice lenses. Copyright (c) 2005 John Wiley & Sons, Ltd.