Pleistocene lakes in southern Israel and Jordan: the environmental conditions of the first step out of Africa
Zusammenfassung der Projektergebnisse
Previously reported Pleistocene lake sediments in southern Israel and Jordan were reexamined during the course of the project. The studied region is currently hyper-arid with a mean annual precipitation of less than 50 mm. As a result, permanent rivers, wetlands and lakes do not exist in the area. However, the presence of Pleistocene mudstones and limestones in several basin settings was used to infer the accumulation of deposits in lakes and to reconstruct significantly wetter conditions in the Pleistocene. Exposed mudstones, marls and authigenic limestones, partly including remains of freshwater organisms (gastropods and ostracods), and the lack of gypsum and other salts mostly suggests deposition in wetland environments. Pleistocene lakes apparently existed only in rare cases such as those of the early Pleistocene Nahal Zihor in the Negev Desert. Based on the types of sediments and faunal remains associated with these water bodies, it is suggested that four relatively wet periods in comparison to current climatic conditions occurred during the early Pleistocene, the middle Pleistocene, the middle section of the late Pleistocene (~ Marine Isotope Stage 3) and its latest section more or less equivalent to the Younger Dryas period in the North Atlantic region. However, a higher number of detailed sedimentological studies including absolute dating of aquatic deposits in the southern Levant is required to improve the knowledge with respect to the temporal history of moisture changes in the region and related climatic changes of air circulation patterns during the Pleistocene. A scientifically surprising result of the project was the observation that almost all postulated ‚lake’ sediments were re-assessed as wetland deposits. Previous geological analyses were apparently often not sufficiently thorough and did often not include palaeontological analyses as probably most powerful tool to distinguish between lacustrine and paludal sediments.
Projektbezogene Publikationen (Auswahl)
- 2012. Ostracods from water bodies in hyperarid Israel and Jordan as habitat and water chemistry indicators. Ecological Indicators, 14: 87-99
Mischke, S., Ginat, H., Al-Saqarat, B., Almogi-Labin, A.
(Siehe online unter https://doi.org/10.1016/j.ecolind.2011.07.017) - 2014. An expanded ostracod-based conductivity transfer function for climate reconstruction in the Levant. Quaternary Science Reviews, 93: 91-105
Mischke, S., Almogi-Labin, A., Al-Saqarat, B., Rosenfeld, A., Elyashiv, H., Boomer, I., Stein, M., Lev, L., Ito, E.
(Siehe online unter https://doi.org/10.1016/j.quascirev.2014.04.004) - 2015. Palaeoenvironmental inferences from late Quaternary sediments of the Al Jafr Basin, Jordan. Quaternary International, 382: 154-167
Mischke, S., Opitz, S., Kalbe, J., Ginat, H., Al Saqarat, B.
(Siehe online unter https://doi.org/10.1016/j.quaint.2014.12.041) - Fossil-based reconstructions of ancient water bodies in the Levantine deserts. In: Enzel, Y. and Bar-Yosef, O. (eds.) Quaternary of the Levant. Cambridge University Press
Mischke, S., Ginat, H., Al Saqarat, B.S., Faerstein, G., Porat, N., Rech, J.
- Pleistocene water bodies and associated geologic deposits in the southern Levant. In: Enzel, Y. and Bar-Yosef, O. (eds.) Quaternary of the Levant. Cambridge University Press
Rech, J.A., Ginat, H., Catlett, G.A., Mischke, S., Winer Tully, E., Pigati, J.S.
- 2016. Paleoclimate reconstruction of the quaternary sediments near the Gulf of Aqaba (Southern Jordan). Arabian Journal of Geosciences, 9: 361 (13 pp.)
Abbas, M., Al-Saqarat, B., Al-Shdaifat, A.
(Siehe online unter https://doi.org/10.1007/s12517-016-2346-5)
