1. Solar-forced 2600 BP and Little Ice Age highstands of the Caspian Sea
- Author
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Kroonenberg, S.B., Abdurakhmanov, G.M., Badyukova, E.N., van der Borg, K., Kalashnikov, A., Kasimov, N.S., Rychagov, G.I., Svitoch, A.A., Vonhof, H.B., and Wesselingh, F.P.
- Subjects
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SOLAR radiation , *GROUND penetrating radar , *MASS spectrometry - Abstract
Abstract: The level of the Caspian Sea, the largest inland sea in the world, has fluctuated capriciously in history, with amplitudes up to 3m in the last century, to 25m in the last millennium, and to over 150m since the Last Glacial. There is little consensus about the causes, and forecasts are contradictory, mainly due to a lack of solid data about past sea levels before 1837 AD, when instrumental observation started. We studied the Holocene Turali barrier complex along the western Caspian shore in Dagestan, Russia. Barrier dynamics during the last 3m sea-level cycle in the past century show that only lagoonal deposits overridden by highstand barriers are suitable for dating former highstands. In the Holocene barrier complex, we selected the most suitable sites for dating using ground penetrating radar (GPR) profiles, outcrops and gravel pits. We obtained 14 accelerator mass spectrometry (AMS) 14C data on in situ double-valved molluscs from highstand lagoonal deposits. The results suggest that the last major highstands occurred around 2600 BP and in the Little Ice Age and coincide with global cooling events associated with minima in solar activity. This suggests that millennial precipitation changes in the Volga River drainage basin are also forced by solar activity. [Copyright &y& Elsevier]
- Published
- 2007
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