Crann, CA, Patterson, RT, Macumber, AL et al. (5 more authors) (2015) Sediment accumulation rates in subarctic lakes: Insights into age-depth modeling from 22 dated lake records from the Northwest Territories, Canada. Quaternary Geochronology, 27. 131 - 144. ISSN 1871-1014
Abstract
Age-depth modeling using Bayesian statistics requires well-informed prior information about the behavior of sediment accumulation. Here we present average sediment accumulation rates (represented as deposition times, DT, in yr/cm) for lakes in an Arctic setting, and we examine the variability across space (intra- and inter-lake) and time (late Holocene). The dataset includes over 100 radiocarbon dates, primarily on bulk sediment, from 22 sediment cores obtained from 18 lakes spanning the boreal to tundra ecotone gradients in subarctic Canada. There are four to twenty-five radiocarbon dates per core, depending on the length and character of the sediment records. Deposition times were calculated at 100-year intervals from age-depth models constructed using the 'classical' age-depth modeling software Clam. Lakes in boreal settings have the most rapid accumulation (mean DT 20±10 yr/cm), whereas lakes in tundra settings accumulate at moderate (mean DT 70±10 yr/cm) to very slow rates, (>100yr/cm). Many of the age-depth models demonstrate fluctuations in accumulation that coincide with lake evolution and post-glacial climate change. Ten of our sediment cores yielded sediments as old as c. 9000cal BP (BP=years before AD 1950). From between c. 9000cal BP and c. 6000cal BP, sediment accumulation was relatively rapid (DT of 20-60yr/cm). Accumulation slowed between c. 5500 and c. 4000cal BP as vegetation expanded northward in response to warming. A short period of rapid accumulation occurred near 1200cal BP at three lakes. Our research will help inform priors in Bayesian age modeling.
Metadata
Item Type: | Article |
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Authors/Creators: |
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Copyright, Publisher and Additional Information: | © 2015. Elsevier. Uploaded in accordance with the publisher's self-archiving policy. NOTICE: this is the author’s version of a work that was accepted for publication in Quaternary Geochronology. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. A definitive version was subsequently published in Quaternary Geochronology, 27,(2015) DOI:10.1016/j.quageo.2015.02.001 |
Keywords: | Accumulation rate; Bacon; Bayesian age-depth modeling; Deposition time; Northwest Territories; Paleolimnology; Subarctic |
Dates: |
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Institution: | The University of Leeds |
Academic Units: | The University of Leeds > Faculty of Environment (Leeds) The University of Leeds > Faculty of Environment (Leeds) > School of Geography (Leeds) |
Depositing User: | Symplectic Publications |
Date Deposited: | 19 Mar 2015 16:00 |
Last Modified: | 16 Jan 2018 07:18 |
Published Version: | http://dx.doi.org/10.1016/j.quageo.2015.02.001 |
Status: | Published |
Publisher: | Elsevier |
Refereed: | Yes |
Identification Number: | 10.1016/j.quageo.2015.02.001 |
Open Archives Initiative ID (OAI ID): | oai:eprints.whiterose.ac.uk:84364 |