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| Titel |
Constraining the Sahara freshwater discharge during sapropel S5 time by a
stable isotope record from the Greater Sirte |
| VerfasserIn |
Eleen Zirks, Michal Kucera, Paul Bachem, Hartmut Schulz |
| Konferenz |
EGU General Assembly 2016
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| Medientyp |
Artikel
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| Sprache |
en
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 18 (2016) |
| Datensatznummer |
250129325
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| Publikation (Nr.) |
 EGU/EGU2016-9420.pdf |
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| Zusammenfassung |
| The Nile River and the Black Sea were long considered as the only significant eastern
Mediterranean freshwater sources and therefore inferred as the primary agents promoting
surface stratification associated with sapropel formation. Sapropel S5, deposited
during the last interglacial, marks a time of possible movement of Homo sapiens out
of Africa. Satellite images revealed the existence of ancient rivers that once ran
through the Sahara desert and drained into the Gulf of Sirte. Anomalous Nd isotope
records from sapropel S5 deposits indicate that these rivers may have been active
during MIS 5e, implying another freshwater source into the eastern Mediterranean
Sea during that period. To constrain the extent of freshwater discharge into the
Mediterranean from the Kufrah River during MIS 5e, a new δ18O record of five
planktonic foraminifera species was generated from sediment core GeoTü SL 96,
located proximal to the assumed outflow of the Kufrah River. The record from core
GeoTü SL 96 compared with seven other records from the eastern Mediterranean Sea
reveal a pattern of oxygen isotope anomalies which implies that the Kufrah River
delivered detectable amount of freshwater during the second part of sapropel S5. These
results reinforce the hypothesis that Sahara river systems were active during MIS 5e,
which has ramifications for the understanding of sapropel events, reconstruction of
coastal landscape, and the better understanding of migration routes of early humans. |
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