Peaks of the North Cascades Range
June 15, 2011
Photographer: Marli Bryant Miller
Summary Author: Marli Bryant Miller
The North Cascades range contains some of the most rugged landscape and the greatest concentration of active alpine glaciers in the lower 48 states. These two items are certainly related. Glaciers eroded steep cliffs or headwalls behind their upper reaches and left sharp peaks behind as erosional remnants called horns. Glaciers also deepened and steepened the valleys so the topographic relief from valley floors to summits typically far exceeds a mile. The bedrock of the North Cascades consists mostly of metamorphic and intrusive igneous rock formed during the coalescence and accretion of terranes to North America during the later part of the Mesozoic Era. Photo taken July 2008.
Photo Details: Camera Maker: Canon; Camera Model: Canon EOS 5D; Lens: EF100-400mm f/4.5-5.6L IS USM; Focal Length: 300.0mm; Aperture: f/9.0; Exposure Time: 0.0013 s (1/800); ISO equiv: 100.