In:
Quaternary Research, Cambridge University Press (CUP), Vol. 74, No. 1 ( 2010-07), p. 156-165
Abstract:
Burial Lake in northwest Alaska records changes in water level and regional vegetation since ∼ 39,000 cal yr BP based on terrestrial macrofossil AMS radiocarbon dates. A sedimentary unconformity is dated between 34,800 and 23,200 cal yr BP. During all or some of this period there was a hiatus in deposition indicating a major drop in lake level and deflation of lacustrine sediments. MIS 3 vegetation was herb-shrub tundra; more xeric graminoid-herb tundra developed after 23,200 cal yr BP. The tundra gradually became more mesic after 17,000 cal yr BP. Expansions of Salix then Betula , at 15,000 and 14,000 cal yr BP, respectively, are coincident with a major rise in lake level marked by increasing fine-grained sediment and higher organic matter content. Several sites in the region display disrupted sedimentation and probable hiatuses during the last glacial maximum (LGM); together regional data indicate an arid interval prior to and during the LGM and continued low moisture levels until ∼ 15,000 cal yr BP. AMS 14 C dates from Burial Lake are approximately synchronous with AMS 14 C dates reported for the Betula expansion at nearby sites and sites across northern Alaska, but 1000–2000 yr younger than bulk-sediment dates.
Type of Medium:
Online Resource
ISSN:
0033-5894
,
1096-0287
DOI:
10.1016/j.yqres.2010.03.007
Language:
English
Publisher:
Cambridge University Press (CUP)
Publication Date:
2010
detail.hit.zdb_id:
1471589-2
detail.hit.zdb_id:
205711-6
SSG:
13
SSG:
14
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