CGRG Bibliography of Canadian Geomorphology
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Author : Campbell, I.D.
Date : 1987
Title : Late Holocene climatic oscillations in the Ruby Range, Yukon Territory, Canada, palynological evidence.
Publication : Paper presented at the International Union for Quaternary Research : XII International Congress, Ottawa, July 31 - August 9, 1987.;
Issue :
Page(s) :
Abstract
Several sites at high altitudes in the Ruby Range, Yukon Territory, yield thin organic soil profiles with the White River Volcanic Ash at the base, overlying till or cobbles. Since this ash is dated at ca. 9000 BP, soil development at these sites appears to have been severely limited for some 8000 years of subaerial exposure. At other sites in the Ruby Range, where sedimentation and soil development started as early as 5000 BP, pollen diagrams indicate an oscillation of the climate between a warm-dry and a cold-wet state. In the longest of these records, the development of peaty horizons clearly correlates with the cold-wet periods. Since the volcanic ash was deposited at the beginning of the most recent (and current) cold-wet period, these sites where the ash is at the base of the organic soil must have been unvegetated during the previous periods of favourable climate for reasons not directly related to the climate. It would appear that the White River Ash provided the sandy substrate needed to develop a significant vascular plant cover. Since such sites cover a significant area at high altitudes in the Ruby Range, the ash would seem to be of some importance in the evolution of the vegetation in this area. (Author)
Bibliography of Canadian Geomorphology