(#) Department of Earth & Atmospheric Sciences, University of Alberta, Edmonton, Canada T6G 2H4.
(*) Department of Geosciences, University of Massachusetts Amherst, MA 01003.
Abstract
A 3300 year composite record of varve sedimentation is presented from High Arctic meromictic Lake C2. The combination of a short runoff and sediment transport season with the strong density stratification of the lake lead to the formation of annual sediment couplets, confirmed by 210Pb determinations. High intra-lake correlation of the varves allowed the construction of a lake-wide composite of varve sedimentation from overlapping segments from multiple sediment cores. Cross-dating between core segments isolated individual errors between cores and identified minor sediment disturbances and vague structures as major sources of error. Resolving errors between cores by cross-dating reduced the chronological error of the composite series to an estimated +/- 57 years.
The Lake C2 varves are the first non-ice, high resolution environmental record from the Canadian High Arctic. The composite varve series compares favorably with other high resolution proxies from the High Arctic, in particular with the ice core records from Devon Island and Camp Century, Greenland. Further details are also revealed about the timing and nature of major ice shelf growth and decay periods on the north coast of Ellesmere Island. Also, a general correspondence between the varve record and other North American proxies for the Little Ice Age period (1400-1900 AD) suggests that the Lake C2 record is sensitive to large-scale synoptic changes.