Multi-proxy-approach in palaeoenvironmental reconstructions using terrestrial sequences from southeastern Transylvania

Abstract

Tephrochronology in terrestrial sediments gained increased attention throughout the last years. Volcanic layers in loess-palaeosol-sequences can be used to enhance the chronostratigraphy and to correlate miscellaneous archives. In southeastern Europe this correlative dating is frequently used, since the region lies in the dispersal area of several regional and supra-regional marker tephra layers. They can be used to put e.g. palaeo-environmental data in a temporal framework. The polygenetic sediment sequence of Bodoc north of Sfântu Gheorghe (Transylvania) and at the bank of the Olt River contains several of such tephra layers. These layers were deposited either subaerial or subaqueous, since this 15 m sequence is of aeolian and fluvial origin. Based on tephra geochemical data and correlations with proximal deposits, we assume the sequence to cover the last glacial cycle. Peculiarly, the sequence shows periglacial features such as ice-wedge casts and cryoturbation, albeit the permafrost boundary during the LGM is thought to be further north (Vandenberghe et al., 2014). Geochemical, magnetic, granulometric and photometric analyses are conducted to reconstruct the local palaeoenvironmental conditions and their implications for southern Transylvanian palaeoclimate. Moreover, the tephra layers are investigated as well as radiocarbon and luminescence dating are applied to obtain a high-resolution chronostratigraphy.

References
Vandenberghe, J., French, H.M., Gorbunov, A., Marchenko, S., Velichko, A.A., Jin, H., Cui, Z., Zhang, T., Wan, X., 2014. The Last Permafrost Maximum (LPM) map of the Northern Hemisphere: permafrost extent and mean annual air temperatures, 25-17 ka BP: The Last Permafrost Maximum (LPM) map of the Northern Hemisphere. Boreas 43, 652–666. https://doi.org/10.1111/bor.12070

Resources

• INTAV_2018_Bodoc.pdf

Bibliography

Pötter, S., Bösken, J., Hambach, U., Veres, D., Karátson, D., Wulf, S., Obreht, I., Markovic, S., Lehmkuhl, F. (2018): Multi-proxy-approach in palaeoenvironmental reconstructions using terrestrial sequences from southeastern Transylvania. INQUA–INTAV International Field Conference and Workshop, Crossing New Frontiers - Tephra Hunt in Transylvania 24.-29.06.2018, Brașov, Romania