Prof. Dr. Werner Ehrmann

Prof. Dr. Gerhard Schmiedl
now: Institut für Geologie und Paläontologie, Universität Hamburg

Dr. Yvonne Hamann
jetzt: Geologisches Institut, ETH Zürich
Dr. Tanja Kuhnt
now: Institut für Geowissenschaften, Universität Frankfurt
Dr. A. Bornemann
Dr. S. Krüger
 

National Cooperation:

Prof. Dr. Ch. Hemleben, Dr. H. Schulz, Dr. W. Siebel
Institut für Geowissenschaften, Universität Tübingen
Prof. Dr. K.-C. Emeis
Institut für Biogeochemie und Meereschemie, Universität Hamburg
Dr. J.-B. Stuut
Fachbereich Geowissenschaften, Universität Bremen
Dr. H. Arz, Dr. P. Dulski
Geoforschungszentrum Potsdam
 
 

International Cooperation:

Prof. Dr. G. Haug
Geologisches Institut, ETH Zürich
Prof. Dr. F. Jorissen
Laboratoire de Géologie, Université d'Angers, Frankreich
Dr. S. Wulf
Institute for Geophysics, University of Austin, USA
   

Project Funding:
Deutsche Forschungsgemeinschaft, Bonn

During METEOR cruise M51/3 several sediment cores were retrieved from bathyal water depths of the Levantine and Aegean seas. The cores contain sediments from the last glacial and Holocene periods and allow the study of paleoceanographic changes at a high temporal resolution. The eastern Mediterranean Sea is very susceptible to both polar and subtropic / tropic climate signals due to its geographic position and marginal setting. Recent studies confirm that the oceanic circulation and marine ecosystems of the eastern Mediterranean Sea reacted very sensitively on short-term climatic fluctuations of different amplitude. These observations are not only important for the study of the climate system itself but are also relevant for social and economic issues in order to assess the potential anthropogenic impact on the densely populated Mediterranean region.
 

Target of the project is the reconstruction of short-term changes in the circulation of eastern Mediterranean subsurface water masses and detritic sediment input from the borderlands and its relation to the climate variability during the last glacial maximum and Holocene (last 20 kyr). This goal shall be achieved through an interdisciplinary approach combining different sedimentological, micropaleontological and isotope geochemical proxies. The major questions are:

1) How and how fast did the weathering processes change on the borderlands as response to short-term climatic variability?

2) How did the abrupt climate changes during the Holocene and the last glacial maximum control the formation and distribution of eastern Mediterranean intermediate and deep water masses? 

3) What impact did the abrupt climate changes of the past 20 kyr have on riverine run-off and nutrient input?

Results:

The results of the studies are documented in several publications and manuscripts.


Publications:

Ehrmann, W., Schmiedl, G., Hamann, Y. & Kuhnt, T. (2007a): Distribution of clay minerals in surface sediments of the Aegean Sea: A compilation. - International Journal of Earth Sciences (Geologische Rundschau), 96: 769-780.

Ehrmann, W., Schmiedl, G., Hamann, Y., Kuhnt, T., Hemleben, C. & Siebel, W. (2007b): Clay minerals in late glacial and Holocene sediments of the northern and southern Aegean Sea. - Palaeogeography, Palaeoclimatology, Palaeoecology, 249: 36-57.

Hamann, Y., Ehrmann, W., Schmiedl, G., Krüger, S., Stuut, J.-B. & Kuhnt, T. (2008): Sedimentation processes in the Eastern Mediterranean Sea during the Late Glacial and Holocene revealed by end-member modelling of the terrigenous fraction in marine sediments. - Marine Geology, 248: 97-114.

Hamann, Y., Ehrmann, W., Schmiedl, G. & Kuhnt, T. (2009): Modern and late Quaternary clay mineral distribution in the area of the SE Mediterranean Sea. - Quaternary Research, 71: 453-464.

Hamann, Y., Wulf, S., Ersoy, O., Ehrmann, W., Aydar, E. & Schmiedl, G. (2010): First evidence of a distal early Holocene ash layer in Eastern Mediterranean deep-sea sediments derived from the Anatolian volcanic province. - Quaternary Research, 73: 497-506.

Kotthoff, U., Pross, J., Schmiedl, G., Bornemann, A., Kaul, C., Koutsodendris, A., Marino, G., Peyron, O. & Schiebel, R. (2010):  Impact of late glacial cold events on the Northern Aegean region reconstructed from marine and terrestrial proxy data. - Journal of Quaternary Science.

Kuhnt, T., Schmiedl, G., Ehrmann, W., Hamann, Y. & Hemleben, C. (2007): Deep-Sea ecosystem variability of the Aegean Sea during the past 22 kyr as revealed by benthic foraminifera. - Marine Micropaleontology, 64: 141-162.

Kuhnt, T., Schmiedl, G., Ehrmann, W., Hamann, Y. & Andersen, N. (2008): Stable isotopic composition of Holocene benthic foraminifers from the Eastern Mediterranean Sea: Past changes in productivity and deep water oxygenation. - Palaeogeography, Palaeoclimatology, Palaeoecology, 268: 106-115.

Schmiedl, G., Kuhnt, T., Ehrmann, W., Emeis, K.-C., Hamann, Y., Kotthoff, U., Dulski, P. & Pross, J. (2010): Climatic forcing of eastern Mediterranean deep-water formation and benthic ecosystems during the past 22 000 years. - Quaternary Science Reviews. 

 


Ph. D. and Diploma Theses:

Hamann, Y. (2008): Late Quaternary climate variability in the Eastern Mediterranean Sea. Dissertation, Universität Leipzig, 165 S.

Kaul, C. (2008): Rekonstruktion spätquartärer ozeanographischer Bedingungen der Ägäis mit Hilfe planktischer Foraminiferen. Diplomarbeit, Universität Leipzig, 95 S.

Kuhnt, T. (2003): Sedimentationsprozesse in der Nordwestlichen Ägäis während des Holozäns. Diplomarbeit, Universität Leipzig, 92 S.

Kuhnt, T. (2008): Reconstruction of late Quaternary deep-sea ecosystem variability in the Eastern Mediterranean Sea based on benthic foraminiferal faunas and stable isotopes. Dissertation, Universität Leipzig, 103 S.

Milker, Y. (2006): Spätquartäre Sedimentationsgeschichte im östlichen Mittelmeer. Diplomarbeit, Universität Leipzig, 75 S.

Schmidt, A. (2007): Reconstruction of the late Quaternary deep-sea ecosystem in the eastern Levantine Basin using benthic foraminifera and stable isotopes. Diplomarbeit, Universität Leipzig, 99 S.

Siebert, D. (2007): Spätquartäre Sedimentationsgeschichte im östlichen Mittelmeer südlich von Zypern. Diplomarbeit, Universität Leipzig, 81 S.

Thieme, K. (2008): Spätquartäre Sedimentationsbedingungen in der zentralen Ägäis abgeleitet von Tonmineralen. Diplomarbeit, Universität Leipzig, 87 S.