extended abstracts - Geomorphic Processes and Geoarchaeology
extended abstracts - Geomorphic Processes and Geoarchaeology
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 />
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