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Asia in Europe? - A direct stratigraphic comparison between the Chinese Loess Plateau and the Middle Danube Basin Loess

Ulrich Hambach1, Mladjen Jovanović2, Slobodan Marković3, Tivadar Gaudenyi4
1 LS Geomorphologie, Universität Bayreuth, Deutschland
2 Department of Geography, University of Novi Sad, Serbia
3 LAPER, University of Novi Sad, Serbia
4 Geographical Institute, Serbian Academy of Science, Serbia

P 1.5 in Progress in Quaternary Stratigraphy

Loess deposits are considered to be some of the most detailed and long-term terrestrial records of Pleistocene climate change. In Eurasia, a unique mid-latitudinal loess-belt ranging from China to South-Eastern Europe provides insights into climate evolution since the Pliocene, at least. Whereas loess deposits in Western and Central Europe are temporarily and spatially discontinuous, in the Lower and Middle Danube Basin, at the western edge of the Eurasian loess belt, one can find true loess plateaus providing almost continuous archives of Pleistocene palaeoclimate. These plateaus were presumably formed under similar environmental conditions like in the Chinese Loess Plateau (CLP) and in other Central Asian loess areas.

In the region called Vojvodina (northern Serbia), we find loess deposits dating back at least to the younger Early Pleistocene and reaching thicknesses of more than 50 m (Marković et al., 2009, 2011). A most remarkable morphological feature is the Titel Loess Plateau (TLP), situated in the interfluve of the Danube and Tisza rivers. Different phases of fluvial erosion have shaped the ellipsoid form of the plateau which is characterised by steep slopes on the margins. In the contrast of that, the plateau surface provides a more smooth morphology with low hypsometric differences. The TLP represents a loess island in the Danube and Tisza floodplains with maximal extension of c. 16 km (NW-SE) and a maximum width of c. 7 km. The loess sequences are comprised of multiple couplets of loess and palaeosol units totalling almost 50 m thickness of sediments (Fig. 1). 5 palaeosol complexes can be distinguished separated by several metres thick loess layers. The lower 2 palaeosol units are developed as strongly rubified forest soils with decreasing degree of pedogenesis from old to young. In contrary, the younger palaeosol units including the recent soil are developed as steppe soils.

Based on inter-profile correlation between three sites at the northern bluffs of the plateau (Veliki surduk, Feudvar and Dukatar) a synthetic TLP profile was built. A detailed magnetic susceptibility (MS) record in combination with palaeopedological observations forms the backbone of the relative stratigraphy. Results from optical dating (Bokhorst et al., 2009) prove the last glacial age of the uppermost loess unit and the thorough palaeopedological study by Bronger (1976) corroborates our interpretations.

The pattern of MS variation and absence of any erosion sign in the profiles suggest a correlation of paleosol complexes V-S5, V-S4, V-S3, V-S2 and V-S1 with the MIS 15-13, 11, 9, 7 and 5, respectively. The new stratigraphic model based on these correlations suggests serious re-interpretations of previous chronological concepts of the TLP loess series. The loess-paleosol sequences at the TLP and in Batajnica (Vojvodina) deposited during the last five interglacial-glacial cycles are characterised by sharp environmental differences between high dust accumulation rates during the glacials and reduced dust fluxes in the periods of palaeosol formation. The revised chronostratigraphic frame for the TLP loess-paleosol sequence provides an opportunity to examine the long term environmental dynamics within the context of regional, continental and global climate changes. Low values of MS and relative high accumulation rates derived from loess units V-L1, V-L2, VL-3, and V-L5 are in good agreement with the relative extent of ice sheets as estimates from marine isotope records (Lisecki and Raymo, 2005).

The distinct and characteristic MS record of the TLP loess-paleosol sequences provides important and significant similarities to the environmental magnetic records observed in other Eurasian loess sections. This opens the possibility to extend the temporal and spatial correlation across the Eurasian loess belt from China via Central Asia to the Middle Danube Basin. A direct correlation of the magnetic susceptibility records from Louchuan (CLP) (Lu et al., 1999) and from the Titel Loess Plateau will be dicussed. Due to high accumulation rates, the Middle and Late Pleistocene loess-paleosol sequences of the TLP preserve a unique aeolian continental record of climate and environmental changes for the last c. 600 kyrs which allows a direct comparison to the loess archives Central Asia and China.

Fig. 1: Direct correlation of the magnetic susceptibility records from Louchuan (CLP) (Lu et al., 1999) and from the Titel Loess Plateau (TLP). Note the striking resemblance in amplitude and shape of the records.
Fig. 1: Direct correlation of the magnetic susceptibility records from Louchuan (CLP) (Lu et al., 1999) and from the Titel Loess Plateau (TLP). Note the striking resemblance in amplitude and shape of the records.

last modified 2012-07-28