Allometry and cirque evolution

A critical appraisal of allometric growth among alpine cirques based on multivariate statistics and spatial analysis

“…Contrary to the approach most commonly adopted in previous studies (Olyphant, 1981a;Evans, 2006Evans, , 2010Barr and Spagnolo, 2013 (1). In the present case they are given by Eq.…”

“…Cirques may also develop beneath ice sheets, with plucking and quarrying processes operating in this case simultaneously on cirque walls and floors (Rudberg, 1984;Hooke, 1991;Richardson and Holmlund, 1996). Within this scientific narrative on the relative roles of cold-climate processes, the concept of allometric growth has been deemed a valid, easily measured proxy for evaluating whether cirque growth is dominated by headwall recession or, instead, by floor lowering (Olyphant, 1981a;Evans, 2006Evans, , 2010 -and thus for inferring which cold-climate process during the Pleistocene contributed most to bedrock denudation (Evans, 2006). The concept of allometric growth comes from biology (Gould, 1966).…”

Numerical modeling of glacial erosion and headwall processes in alpine valleys

“…Observations of seasonal rock avalanches have led to many measurements of the rate of headward erosion, which range between 0.001 mm and 5 mm/year (see Table 2 for a summary). Significant recent evidence suggests that valleys elongate over time because of headward erosion (Andrews and LeMasurier, 1973;Olyphant, 1981;Brocklehurst and Whipple, 2002;Oskin and Burbank, 2005;Naylor and Gabet, 2007). The appearance of fresh glacial valleys 'consuming' high plateaus is another sign of active headwall processes (e.g., Anderson et al, 2006b).…”

Ice thickness and topographic relief in glaciated landscapes of the western USA

“…Spectacular moraines on the eastern side of the range (e.g., Johnson et al, 1987) imply substantially more glacial erosion on this side of the range, presumably reflecting the effects of wind-blown snow crossing the range from west to east (e.g., Brocklehurst and MacGregor, 2005), and the North American monsoon system bringing precipitation from the Gulf of Mexico (e.g., Higgins et al, 1997;Poore et al, 2005). The glacial history is summarised by McCalpin (1981), while additional research has focussed on cirque evolution (e.g., Olyphant, 1981) and rock glaciers (e.g., Burger et al, 1999).…”