Start of the last interglacial period at 135 ka: Evidence from a high Alpine speleothem
- 1Institut für Geologie und Paläontologie, Universität Innsbruck, Innrain 52, 6020 Innsbruck, Austria
- 2Forschungsstelle Radiometrie, Heidelberger Akademie der Wissenschaften, Im Neuenheimer Feld 229, 69120 Heidelberg, Germany
- 3Department of Geosciences, Morrill Science Center, University of Massachusetts, Amherst, Massachusetts 01003, USA
Abstract
A detailed study of growth periods of a flowstone from Spannagel Cave in the Zillertal Alps (Austria) at ∼2500 m above sea level, a site highly sensitive to climate changes, offers unprecedented new insights into Pleistocene climate change in Central Europe. Flowstone sample SPA 52 has a high U content (to 116 ppm); analyses of this sample reveal that episodes of calcite deposition started at 204 ± 3 ka, 135 ± 1.2 ka, and 122 ka, suggesting that at these times, the mean air temperature at this high Alpine site was within 1.5 °C of the present-day condition. The beginning of growth at 135 ka corresponds to the ending of the last glaciation and is concordant with a midpoint age for the penultimate deglaciation at 135 ± 2.5 ka, as deduced from the absolutely dated oxygen isotope curve in sediments from the Bahamas, as well as with recent coral evidence from Barbados indicating a high sea level already by 135.8 ± 0.8 ka. This set of data supports evidence against Northern Hemisphere forcing of termination II, because the insolation maximum is at 127 ka.
Footnotes
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↵GSA Data Repository item 2002095, Table 1, Th-U dates, is available on request from Documents Secretary, GSA, P.O. Box 9140, Boulder, CO 80301-9140, USA, editinggeosociety.org, or at www.geosociety.org/pubs/ft2002.htm.
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- Accepted May 15, 2002.
- Received November 2, 2001.
- Revision received May 7, 2002.
- Geological Society of America
