Reconstruction of microenvironmental changes in the Kopasz Hill loess area at Tokaj (Hungary) between 15 and 70 ka BP.

Abstract

We collected 11 Kopasz Hill loess profiles for paleoecological and geochronological analysis. The loess accumulation and development formed during the last (Weichselian) glacial period between 70 and 15 ka BP. We found that the majority of the loess profiles were composed of three typical loess strata and two well-developed paleosol horizons. Based on vertebrate remains, the lowest loess layer formed between 70-50 ka BP, during the first cool and dry climatic phase of the last glacial period, when forest steppe vegetation dominated in the Kopasz Hill area. On the surface of the lowermost layer, a paleosol developed between 50 and 40 ka BP as an indication of a more humid and warmer climatic phase. This paleosol layer was buried by a new loess layer that developed between 40 and 32 ka BP. The upper paleosol horizon developed between 32 and 26 ka BP. Molluscs preferring a mild climate were found in this layer, suggesting that this phase was wet and relatively temperate. A number of fired macrocharcoal remains can be found on the top of this paleosol layer. Charcoal samples from nine sites were dated by radiocarbon analyses. These results reflect the presence of a charcoal-rich horizon that developed 28-26 ka BP. Ca. 26 ka BP, loess formation resumed. We analyzed 14 samples from 6 sites by the (super 14) C method. Based on (super 14) C data, the uppermost part of loess profiles developed between 26 and 15 ka BP.