Hostname: page-component-586b7cd67f-l7hp2 Total loading time: 0 Render date: 2024-11-23T20:49:25.292Z Has data issue: false hasContentIssue false
  • English
  • Français

Radiocarbon Reservoir Ages from Freshwater Lakes, South Georgia, Sub-Antarctic: Modern Analogues from Particulate Organic Matter and Surface Sediments

Published online by Cambridge University Press:  18 July 2016

Steven G Moreton ,
Gunhild C Rosqvist ,
Sarah J Davies  and
Michael J Bentley
Steven G Moreton
Affiliation:
NERC Radiocarbon Laboratory, Scottish Enterprise Technology Park, East Kilbride, G75 0QF, United Kingdom. Corresponding author. Email: [email protected]
Gunhild C Rosqvist
Affiliation:
Department of Physical Geography, Stockholm University, S-106 91 Stockholm, Sweden
Sarah J Davies
Affiliation:
Institute of Geography and Earth Sciences, University of Wales Aberystwyth, Llandinam Building, Aberystwyth, SY23 3DB, United Kingdom
Michael J Bentley
Affiliation:
Department of Geography, University of Durham, Science Site, South Road, Durham, DH1 3LE, United Kingdom
Rights & Permissions [Opens in a new window]

Abstract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

Lake sediments have the potential to preserve proxy records of past climate change. Organic material suitable for radiocarbon dating often provides age control of such proxy records. Six shallow freshwater lakes on the sub-Antarctic island of South Georgia were investigated for carbon reservoir effects that may influence age-depth profiles from lake sediment records in this important region. Paired samples of particulate organic matter (POM) from the water column and surface sediment (bulk organic carbon) were analyzed by accelerator mass spectrometry 14C. POM in 4 lakes was found to be in equilibrium with the atmosphere (~107% modern), whereas 2 lakes showed significant depletion of 14C. In each lake, the surface sediment ages were older than the paired POM age. Surface sediment ages showed a much greater range of ages compared to the equivalent POM ages, even for lakes located in close proximity. We conclude that sediment disturbance during coring, bioturbation, and periodic resuspension of sediments are likely factors causing the difference in the apparent age of surface sediments.

Type
Part II
Information
Radiocarbon , Volume 46 , Issue 2: Proceedings of the 18th International Radiocarbon Conference (Part 2 of 2), Conference Editors: Nancy Beavan Athfield, Rodger J Sparks , 2004 , pp. 621 - 626
Copyright
Copyright © The Arizona Board of Regents on behalf of the University of Arizona 

References

Birnie, J. 1990. Holocene environmental change in South Georgia: evidence from lake sediments. Journal of Quaternary Science 5:171–87.Google Scholar
Björck, S, Håkansson, H, Zale, R, Karlén, W, Jönsson, BL. 1991b. A Late Holocene lake sediment sequence from Livingston Island, South Shetland Islands, with palaeoclimatic implications. Antarctic Science 3(1):61–72.Google Scholar
Björck, S, Hjort, C, Ingólfsson, Ó, Skog, G. 1991a. Radiocarbon dates from the Antarctic Peninsula region—problems and potential. Quaternary Proceedings 1:55–65.Google Scholar
Björck, S, Olsson, S, Ellis-Evans, C, Håkansson, H, Humlum, O, de Lirio, JM. 1996. Late Holocene palaeoclimatic records from lake sediments on James Ross Island, Antarctica. Palaeogeography, Palaeoclimatology, Palaeoecology 121:195–220.Google Scholar
Doran, PT, Berger, GW, Lyons, WB, Wharton, RA Jr, Davisson, ML, Southon, J, Dibb, JE. 1999. Dating Quaternary lacustrine sediments in the McMurdo Dry Valleys, Antarctica. Palaeogeography, Palaeoclimatology, Palaeoecology 147:223–39.CrossRefGoogle Scholar
Gordon, JE, Harkness, DD. 1992. Magnitude and geographic variation of the radiocarbon content in Antarctic marine life: implications for reservoir corrections in radiocarbon dating. Quaternary Science Reviews 11:697–708.CrossRefGoogle Scholar
Hall, BL, Henderson, GM. 2001. Use of uranium-thorium dating to determine past 14C reservoir effects in lakes: examples from Antarctica. Earth and Planetary Science Letters 193:565–77.CrossRefGoogle Scholar
Hjort, C, Ingólfsson, Ó, Möller, P, Lirio, JM. 1997. Holocene glacial history sea-level changes on James Ross Island, Antarctic Peninsula. Journal of Quaternary Science 12(4):259–73.Google Scholar
Ingólfsson, Ó, Hjort, C, Björck, S, Smith, RIL. 1992. Late Pleistocene and Holocene glacial history of James Ross Island, Antarctic Peninsula. Boreas 21:209–22.CrossRefGoogle Scholar
Jones, VJ, Hodgson, DA, Chepstow-Lusty, A. 2000. Palaeolimnological evidence for marked Holocene environmental changes on Signy Island, Antarctica. The Holocene 10(2):43–60.Google Scholar
Levin, I, Kromer, B. 1997. Twenty years of atmospheric 14CO2 observations at Schauinsland Station, Germany. Radiocarbon 39(2):205–18.Google Scholar
Rosqvist, GC, Rietti-Shati, M, Shemesh, A. 1999. Late glacial to middle Holocene climatic record of lacustrine biogenic silica isotopes from a Southern Ocean island. Geology 27:967–70.Google Scholar
Rosqvist, G, Schuber, P. 2003. Millennial-scale climate changes on South Georgia, Southern Ocean. Quaternary Research 59(3):470–75.Google Scholar
Skidmore, MJ. 1972. The geology of South Georgia: 3. Prince Olav Harbour and Stromness Bay areas. British Antarctic Survey Scientific Reports 73:50.Google Scholar
Stuiver, M, Denton, GH, Hughes, TJ, Fastook, JL. 1981. History of the marine ice sheet in west Antarctica during the last glaciation, a working hypothesis. In: Denton, GH, Hughes, TH, editors. The Last Great Ice Sheets. New York: Wiley-Interscience. p 319–436.Google Scholar
Takahashi, HA, Wada, H, Nakamura, T, Miura, H. 1999. 14C anomaly of freshwater algae in Antarctic coastal ponds and lakes. Polar Science 12:248–57.Google Scholar
Wasell, A, Håkansson, H. 1992. Diatom stratigraphy in a lake on Horseshoe Island, Antarctica: a marine-brackish-freshwater transition with comments on the systematics and ecology of the most common diatoms, Diatom Research 7:157–94.Google Scholar
Zale, R, Karlén, W. 1989. Lake sediment cores from the Antarctic Peninsula and surrounding islands. Geografiska Annaler 71(A):211–20.Google Scholar