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extended abstracts - Geomorphic Processes and Geoarchaeology

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<strong>Geomorphic</strong> processes <strong>and</strong> geoarchaeology<br />

also proves the presence of the ancient humus formation in all three soils. Corg content in<br />

pedogenic horizons is 2-4 times increased comparing with lacustrine <strong>and</strong><br />

proluvial sediments.<br />

Carbonate content is high in all specimens, more that 30 %. This is not surprising<br />

as all these studied soils <strong>and</strong> sediments derivated from the weathering <strong>and</strong> re-deposition<br />

of the Cretaceous chalky material. But A1 soil horizons <strong>and</strong> lacustine sediments are<br />

slightly depleted (30-31 %), while proluvial-deluvial sediments have slightly elevated 33-<br />

36 % carbonate concentrations.<br />

All three paleosols <strong>and</strong> especially the upper one have the elevated concentration of<br />

Fe oxides determined by different methods (Tamm, Merha <strong>and</strong> Jackson, Bascomb). The<br />

Alleroed paleosol has the increased content of Al <strong>and</strong> Mn oxides (after Tamm).<br />

Thus, two main late Valdai intervals of various genesis were found in Divnogor’e<br />

9, indicating two various sedimentation regimes. The lower interval represents proluviallacustrine<br />

sedimentation of dammed basin, <strong>and</strong> the upper is pedo-deluvial (slope)<br />

interval. The lower interval is characterized by the interchange of cyclic layered clayey,<br />

fine <strong>and</strong> intermediate loamy subhorizontal layers (lacustrine batch) with fine <strong>and</strong><br />

intermediate loamy layers containing the inclusions of chalky Cretaceous fragments of<br />

variable size <strong>and</strong> roundness (of proluvial genesis). The upper interval is represented by<br />

the interchanging of weakly developed paleosols with talus layers <strong>and</strong> proluvial-deluvial<br />

loams. The pit is underlied by well developed soddy calcareous soil (Rendzina) of the<br />

Holocene age, which in its turn is recovered by agro-deluvial sediments.<br />

Three levels were identified indicating the late Valdai weakly developed soils with<br />

various genesis <strong>and</strong> degree of preservation. Their age is younger than the age of the bonebearing<br />

layer, but older than Holocene. The upper soil (expected to be of the Alleroed<br />

age) is represented by the ferruginous horizon, which is also marked by the small<br />

increasing of humus <strong>and</strong> Fe, Al, Mn oxides. This soil is preliminary correlated with<br />

weakly developed brown forest soil. The intermediate soil contains two horizons: weakly<br />

developed humus <strong>and</strong> carbonate horizons identified by the increased humus <strong>and</strong><br />

carbonates contents respectively. This soil is identified as weakly developed soddycalcareous<br />

soil (Rendzina). The lower soil is the most developed <strong>and</strong> humus rich,<br />

identified as the weakly developed meadow-calcareous soil.<br />

The lower <strong>and</strong> intermediate soils were formed under the forest-steppe periglacial<br />

environment. The upper soil is expected to be formed under forest periglacial<br />

environment. It is likely that all three soils reflect the short (n 10 1-2 years) periods<br />

corresponding to one or two warming periods (interphasials). Two lower soils correspond<br />

to the first drier stage, while the upper soil reflects the second wetter stage. It may occur<br />

that the soils reflect two warming periods. In this case the lower soil indicates the first<br />

(Boelling?), <strong>and</strong> the second humic soil <strong>and</strong> third brown soil correspond to the second<br />

warming period (Alleroed?).<br />

References<br />

1. Bessudnov A.A., Bessudnov A.N. 2010. New Upper Paleolithic monuments near<br />

Divnogor’e in the Middle Don. Russian Archeology, No. 2, P. 13-20 (in Russian).<br />

2. Lavrushin Yu.A., Bessudnov A.N., Spiridonova Е.А. et al. 2011. High resolution<br />

sequence of the local natural events in the middle part of European Russia. Vestnik VSU,<br />

Series: geology, No. 2, P. 26-39.<br />

269

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