Glacial History of Wolf Creek, St. Elias Range, Canada

摘要: Remnants of late Wisconsin drift on bedrock benches 800-1,500 feet above Wolf Creek are the oldest evidence glaciation recognized. Deposits very latest and possibly, in part, earliest post-Wisconsin product a limited advance or extended pause recession from climax. Glacier was then at least several hundred thicker, its terminus not less than 4 5 miles beyond present snout. Post-Wisconsin xerothermic conditions caused extensive ice shrinkage, glaciers become smaller present. During this period an valley train formed, alluvial cones fans were built, mature white spruce forest developed up-valley to natural tree line. A subsequent expansion readvance culminated between 1840 1890. Large raw lateral terminal moraines trim line principal manifestations advance, which is believed be climatic, rather orogenic seis...