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Separation and 14C Dating of Pure Pollen from Lake Sediments: Nanofossil AMS Dating

Published online by Cambridge University Press:  18 July 2016

Austin Long ,
Owen K. Davis  and
Jeanne de Lanois
Austin Long
Affiliation:
Department of Geosciences, The University of Arizona, Tucson, Arizona 85721 USA
Owen K. Davis
Affiliation:
Department of Geosciences, The University of Arizona, Tucson, Arizona 85721 USA
Jeanne de Lanois
Affiliation:
Department of Geosciences, The University of Arizona, Tucson, Arizona 85721 USA
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Abstract

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We have developed and tested a practical device for manually separating pollen from pollen concentrates in sufficient quantity for AMS 14C dating. It is a combination of standard, commercially available equipment handled in a clean room by an individual trained to recognize pollen. A typical example requires about 15–20 h of hand-picking under the microscope. We show the usefulness of this procedure with results on a mid-Holocene segment from a core from Mono Lake. Sediments from this hardwater lake contain pollen and finely disseminated organic matter, but no macrofossils. The pollen dated ca. 1000 yr younger than the bulk sediment. The sediment “date” is most likely affected by incorporation of limestone-derived carbon, and is erroneously old.

Type
II. Applied Isotope Geochemistry
Information
Radiocarbon , Volume 34 , Issue 3: Proceedings of the 14th International Radiocarbon Conference , 1992 , pp. 557 - 560
Copyright
Copyright © The American Journal of Science 

References

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