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<jats:title>Abstract</jats:title><jats:p>Very high‐resolution photogrammetric and geodetic measurements about the deformation of transverse ridges on Murtèl, Muragl and Suvretta rock glaciers in the Swiss Alps are discussed. The ridges are advected downstreams with a speed that equals the overall speed of the creeping permafrost within the significance level of the applied techniques. Any process of ridge formation is, thus, overlain on the mass creep. In fact, measurements yield local speed maxima on top of the ridges that can be explained by differential movement due to ridge growth through bulging under compressive flow. This hypothesis is consistent with results from laboratory experiments that were performed on a model ramp employing mixtures of Xanthan Gum, sand and gravel. Indications were also found that overthrusting is involved in the development of transverse ridges on rock glaciers. Copyright © 2004 John Wiley &amp; Sons, Ltd.</jats:p>

<jats:title>Abstract</jats:title><jats:p>Solifluction lobes and rock glaciers show similar geometry with a wide range of sizes. Morphometric analysis classifies these lobate landforms in the eastern Swiss Alps into five subgroups. <jats:italic>A bouldery rock glacier</jats:italic> has an active layer composed of matrix‐free boulders, whereas <jats:italic>a pebbly rock glacier</jats:italic> consists of matrix‐supported debris derived from less resistant rocks. Both move by permafrost creep at 5–30 m depth, but the former tends to have a longer tread. <jats:italic>A high solifluction lobe</jats:italic>, having a riser 0.2–3 m high, originates mainly from annual gelifluction operating within the top 0.5 m of sediment, and its variation, <jats:italic>a mudflow‐affected high solifluction lobe</jats:italic>, occurs where prolonged snowmelt triggers a rapid flow of the thawed surficial layer. <jats:italic>A low solifluction lobe</jats:italic> has a riser up to 0.2 m high and occurs where thin fine‐grained debris responds mainly to diurnal frost creep. These lobes show, on the whole, positive relations between the tread length (<jats:italic>L</jats:italic>), width (<jats:italic>W</jats:italic> ) and the riser height (<jats:italic>H</jats:italic> ). However, a regression analysis separates the rock glaciers from the solifluction lobes by a distinct gap at <jats:italic>W</jats:italic> (or <jats:italic>L</jats:italic>)=30 m and <jats:italic>H</jats:italic>=3 m and provides different regression lines for the two populations. The morphometry primarily determined by the transport process is <jats:italic>H</jats:italic>, which approximates or slightly exceeds the maximum depth of movement. The depth of movement also affects the horizontal extent of a moving mass, which defines <jats:italic>W</jats:italic>. A lobe appears where horizontal homogeneity exceeds 3<jats:italic>H</jats:italic>, and advances with time until reaching a maximum <jats:italic>L</jats:italic> controlled by climatic or dynamic conditions. Lobe morphometry can be used as an environmental indicator. Copyright © 2005 John Wiley &amp; Sons, Ltd.</jats:p>

<jats:title>Abstract</jats:title><jats:p>Photogrammetric measurements of surface movement, 1981–94, on the Muragl glacier forefield (Swiss Alps) are compared to direct current resistivity surveys for the same area. At three locations isolated patches of frozen sediments were inferred, each about 10,000–20,000 m<jats:sup>2</jats:sup> in area. These were deforming at surface velocities of up to 50 cm per year. The locations where creep was observed coincide well with areas where two‐dimensional (2D) resistivity surveys suggest ice is present within the ground. Copyright © 2005 John Wiley &amp; Sons, Ltd.</jats:p>