Th/U dating of frozen peat, Bol'shoy Lyakhovsky Island (northern Siberia)
The chronology of Quaternary paleoenvironment and climate in northeastern Siberia is poorly understood due to a lack of reliable numerical age determinations. The best climatic archives are ice-rich permafrost sequences, which are widely distributed in northeastern Siberia. For this study, 230Th/U-a...
Published in: | Quaternary Research |
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Main Authors: | , , |
Format: | Article in Journal/Newspaper |
Language: | unknown |
Published: |
Cambridge University Press (CUP)
2002
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Subjects: | |
Online Access: | https://epic.awi.de/id/eprint/57874/ https://epic.awi.de/id/eprint/57874/1/Schirrmeister_2002_QR.pdf https://hdl.handle.net/10013/epic.e79a4765-cfba-400f-ac65-4f29c930baae |
Summary: | The chronology of Quaternary paleoenvironment and climate in northeastern Siberia is poorly understood due to a lack of reliable numerical age determinations. The best climatic archives are ice-rich permafrost sequences, which are widely distributed in northeastern Siberia. For this study, 230Th/U-ages were determined by thermal ionization mass spectrometry (TIMS) from frozen peat in a permafrost deposit at the southern cliff of the Bol'shoy Lyakhovsky Island (New Siberian Archipelago), west of the Zimov'e River. These yielded a Pre-Eemian "isochron"-corrected 230Th/U- age of 200,900 ± 3400 yr. This result is reliable because permafrost deposits behave as closed systems with respect to uranium and thorium. Our findings suggest that 230Th/U dating of frozen peat in permafrost deposits is a useful tool for the reconstruction of the Middle Quaternary environment of northern Siberia and of the whole Arctic. © 2002 University of Washington. |
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