Radiocarbon Dating of Lacustrine Strands in Arctic Alaska

Аннотация

Reports on 1958-64 studies of lacustrine processes and basin sequences in the Pt Barrow region. Lakes developed in the ice-rich late Pleistocene Gubik Formation are surrounded by two to four exposed and revegetated wave-cut shelves which suggest regional correlative cycles of piracy due to minor shifts in climate and eustatic level. Shelves exposed when lakes are intersected by tundra streams and drained, require 10-20 yr for revegetation in the present climate. Radiocarbon dates of samples from abandoned strands show the majority to be <3500 yr old. The postglacial transgressive-regressive lacustrine cycle is described and diagrammed. The lacustrine maximum transgression probably occured near the end of the hypsithermal (3500-4000 BP) and the onset of the post-hypsithermal cooling phase was synchronous with the initial period of draining. More systematic investigation is required however, before clear time correlation of geomorphic surfaces and events can be established.