Location of Repository

A 40,000-yr record of environmental change from Burial Lake in Northwest Alaska

By Mark B. Abbott, Mary E. Edwards and Bruce P. Finney

Abstract

Burial Lake in northwest Alaska records changes in water level and regional vegetation since ?39,000 cal yr<br/>BP based on terrestrial macrofossil AMS radiocarbon dates. A sedimentary unconformity is dated between<br/>34,800 and 23,200 cal yr BP. During all or some of this period there was a hiatus in deposition indicating a<br/>major drop in lake level and deflation of lacustrine sediments. MIS 3 vegetation was herb-shrub tundra;<br/>more xeric graminoid-herb tundra developed after 23,200 cal yr BP. The tundra gradually became more<br/>mesic after 17,000 cal yr BP. Expansions of Salix then Betula, at 15,000 and 14,000 cal yr BP, respectively, are<br/>coincident with a major rise in lake level marked by increasing fine-grained sediment and higher organic<br/>matter content. Several sites in the region display disrupted sedimentation and probable hiatuses during the<br/>last glacial maximum (LGM); together regional data indicate an arid interval prior to and during the LGM<br/>and continued low moisture levels until ?15,000 cal yr BP. AMS 14C dates from Burial Lake are approximately<br/>synchronous with AMS 14C dates reported for the Betula expansion at nearby sites and sites across northern<br/>Alaska, but 1000–2000 yr younger than bulk-sediment dates

Year: 2010
OAI identifier: oai:eprints.soton.ac.uk:158377
Provided by: e-Prints Soton
Download PDF:
Sorry, we are unable to provide the full text but you may find it at the following location(s):
  • http://dx.doi.org/10.1016/j.yq... (external link)
  • Suggested articles


    To submit an update or takedown request for this paper, please submit an Update/Correction/Removal Request.