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14C AMS Dating of Icelandic Lake Sediments

Published online by Cambridge University Press:  18 July 2016

Árný E. Sveinbjörnsdóttir ,
Jan Heinemeier ,
Peter Kristensen ,
Niels Rud ,
Áslaug Geirsdóttir  and
Jórunn Harđardóttir
Árný E. Sveinbjörnsdóttir
Affiliation:
Science Institute, University of Iceland, Dunhagi 3, IS-107 Reykjavik, Iceland
Jan Heinemeier
Affiliation:
AMS 14C Dating Laboratory, Institute of Physics and Astronomy, University of Aarhus, DK-8000 Aarhus C, Denmark
Peter Kristensen
Affiliation:
Department of Earth Sciences, University of Aarhus, DK-8000 Aarhus C, Denmark
Niels Rud
Affiliation:
AMS 14C Dating Laboratory, Institute of Physics and Astronomy, University of Aarhus, DK-8000 Aarhus C, Denmark
Áslaug Geirsdóttir
Affiliation:
Department of Geosciences, University of Iceland, IS-101, Reykjavik, Iceland
Jórunn Harđardóttir
Affiliation:
INSTAAR, Campus Box 450, University of Colorado, Boulder, Colorado 80309, USA
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Abstract

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We report an age-depth profile for the sediments of the Lake Hesrvatn, southern Iceland, based on 14C analyses of the organic fraction of bulk sediment samples, molluscs and foraminifera. Our age-depth curve is supported by the occurrence of the well-dated Vedde ash in the lowermost part of the sediments. Comparison of foraminifera dates with the age of the Vedde ash indicates a reservoir age of ca. 400 yr. The results suggest that the sediments at Hestvatn accumulated in a marine environment until ca. 8700 bp and thereafter in freshwater.

Owing to the lack of terrestrial macrofossils and the low concentration of molluscs and foraminifera, we were forced to attempt to date most of the core with the organic fraction of the bulk sediment samples. We found, however, that this fraction is not homogeneous in density or 14C age. We believe that during sample pretreatment we managed to isolate a light organic fraction, which closely represents the true age of the sediment, whereas the denser fraction yields ages that are too high. This age diversity may to some extent be explained by the large drainage area of the lake, from which plant remains of different ages may have been washed into the lake.

Type
Part 2: Applications
Information
Radiocarbon , Volume 40 , Issue 2: 16th International Radiocarbon Conference June 16-20, 1997 Part 2: Applications, Conference Editors: Willem G. Mook Johannes van der Plicht , 1997 , pp. 865 - 872
Copyright
Copyright © The American Journal of Science 

References

Andersen, G. J., Heinemcier, J., Nielsen, H. L., Niels, R., Thomsen, M. S., Johnsen, S., Sveinbjörnsdóttir, Á. E. and Hjartarson, Á. 1989 AMS 14C dating on the Fossvogur sediments, Iceland. In Long, A., Kra, R. S. and Srdoč, D., eds., Proceedings of the 13th International 14C Conference. Radiocarbon 31(3): 592–600.Google Scholar
Bard, E., Arnold, M., Mangerud, J., Paterne, M., Labeyrie, L., Duprat, J., Mélières, M.-A., Sønstegaard, E. and Duplessy, J.-C. 1994 The North Atlantic atmosphere-sea surface 14C gradient during the Younger Dryas climatic event. Earth and Planetary Science Letters 126: 275–287.Google Scholar
Björck, S., Ingólfsson, Ó., Haflidason, H., Hallsdóttir, M. and Anderson, N. J. 1992 Lake Torfadalsvatn: A high resolution record of the North Atlantic ash zone I and the last glacial-interglacial environmental changes in Iceland. Boreas 21: 15–22.Google Scholar
Geirsdóttir, Á., Hallsdóttir, M. and Harórdóttir, J. (ms.) 1995 Environmental change in southern Iceland during the Holocene. Second annual PALE Research Meeting – Abstracts. 4–6 February 1995. University of Washington, Pack Forest, Eatonville, Washington. 6 p.Google Scholar
Geirsdóttir, Á. and Harórdóttir, J. 1995. Lake sediment coring in southern lowlands of Iceland. The Paleo Times: The Paleoclimate of Arctic Lakes and Estuaries Newsletter 3: 11.Google Scholar
Geirsdóttir, Á. and Harórdóttir, J. 1996 Studies of environmental change from the late glacial and Holocene in southern and western Iceland. The Paleo Times: The Paleoclimate of Arctic Lakes and Estuaries Newsletter 4: 18.Google Scholar
Geirsdóttir, Á. and Harórdóttir, J. 1997 The implications of lake sedimentary studies in south and west Iceland. The Paleo Times: The Paleoclimate of Arctic Lakes and Estuaries Newsletter 5: 5.Google Scholar
Geirsdóttir, Á., Harórdóttir, J. and Eiríksson, J. 1997 The depositional history of the Younger Dryas–Preboreal Búǒi moraines in south-central Iceland. Arctic and Alpine Research 29: 13–23.Google Scholar
Harǒardóttir, J., Geirsdóttir, Á. and Sveinbjörnsdóttir, A. E. (ms.) 1996 New finding regarding the deglaciation of southern Iceland; evidence from lake sediments. Paper presented at the GSA Annual Meeting, October 28–31, 1996. Denver, Colorado.Google Scholar
Jóhannesson, H., Grönvold, K. and Sveinbjörnsdóttir, Á. E. (ms.) 1994 Ófærugil ravine. Tephrochronology below Hekla layer 5. Paper presented at the Geoscience Society of Iceland, Spring Meeting.Google Scholar
Nesje, A. 1992 A piston corer for lacustrine and marine sediments. Arctic and Alpine Research 24: 257–259.CrossRefGoogle Scholar
Sveinbjörnsdóttir, Á. E., Heinemeier, J., Rud, N. and Johnsen, S. 1992 14C anomalies observed for plants growing in Icelandic geothermal waters In Long, A. and Kra, R. S., eds., Proceedings of the 14th International 14C Conference. Radiocarbon 34(3): 696–703.Google Scholar
Vogel, J. S., Southon, J. R., Nelson, D. E. and Brown, T. A. 1984 Performance of catalytically condensed graphite for use in accelerator mass spectrometry. In Wölfli, W., Polach, H. A. and Anderson, H. H., eds., Proceedings of the 3rd International Symposium on Accelerator Mass Spectrometry. Nuclear Instruments and Methods in Physics Research 233 (B5): 289–293.Google Scholar