Neoglacial Glacier Fluctuations in the Canadian Rockies

Abstract

The Little Ice Age was the most extensive Neoglacial glacier advance in the Canadian Rockies. Evidence of earlier, less-extensive Neoglacial glacier advances is based on wood recovered from several glacier forefields. Wood flushed out of Athabasca Glacier (7550-8230 yr B.P., three dates) and Dome Glacier (6120-6380 yr B.P., two dates) indicates that forests occurred upvalley of present glacier termini during the Hypsithermal. Detrital logs from Peyto (14 dates), Saskatchewan (3 dates), Robson (3 dates), and Yoho (1 date) Glaciers, plus in situ slumps at Peyto and Robson Glaciers, have yielded 14 C dates between 2490 and 3300 yr B.P. (12 dates between 2800 and 2990). This wood is derived from sources at or upvalley from present glacier termini and represents forests overridden by glaciers between ca. 3100 and 2500 yr B.P. (Treeline was higher than present immediately prior to this advance.) This advance, which did not extend beyond the Little Ice Age maximum position, is designated the Peyto Advance and correlated with the Tiedemann Advance in western British Columbia. Earliest Little Ice Age advances at Peyto and Robson Glaciers are dated ca. 800-600 yr B.P. at positions ca. 500 m upvalley from Little Ice Age limits.