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Elevation As A Control Of Boulder Stream Formation In The Blue Ridge Province Of Virginia, Marc D. Zamkotowicz

OES Theses and Dissertations

Within four study areas in the Blue Ridge Mountains of Virginia, boulder streams formed by periglacial processes carpet the bottoms of most high-altitude first-order valleys. The geomorphic indicators of periglacial formation in these long, linear accumulations of bouldery colluvium - the presence of vertical clasts, gradational upper contacts with talus deposits, confinement within valleys, and hump-like cross sectional profiles - were present in all areas mapped and in most individual boulder streams. The minimum critical elevation for boulder stream formation increases from north to south across Virginia, from 150 m in elevation in northern Virginia to 1500 m in southwestern …