Morphometry and environmental characteristics of turf‐banked solifluction lobes, Kluane Range, Yukon Territory, Canada

Measurements of turf‐banked solifluction lobes at a site in the Kluane Range, Yukon Territory, are compared to observations made by L.W. Price of similar features located 50 km to the north in the Ruby Range. Both studies show that a threshold depth of snow is necessary for lobes to develop. The relative importance of solifluction on slopes with different orientations, however, is not congruent. The largest lobes at our site are present on northeast‐facing slopes and the smallest on northwest‐facing slopes. Lobe dimensions increase downslope in association with a greater organic mat thickness, a higher soil fines content, and a reduced late‐summer thaw depth. Riser heights that are large relative to tread length‐to‐width ratios are correlated with a thin organic mat, a thick active layer and a high coarse particle content. The lobe plan‐form, described by the ratio of tread length to tread width, is significantly correlated with only one biophysical variable. Mean and median length‐to‐width ratios are below unity for all aspects at our site and in several other studies, suggesting a common evolutionary form. A cycle of solifluction lobe development is proposed, in which a lobe enlarges to a maximum size that depends on micro‐site environmental characteristics. Copyright © 2002 John Wiley & Sons, Ltd.