Wyniki wyszukiwania - BazTech

1

Absolute chronology of fluvial events in the Upper Dnieper River system and its palaeogeographic implications

Panin A. V., Adamiec G., Arslanov K. A., Bronnikova M. A., Filippov V. V., Sheremetskaya E. D., Zaretskaya N. E., Zazovskaya E. P.

Geochronometria

|

2014

|

Vol. 41, no. 3

278--293

EN

A set of 121 radiocarbon and OSL dates has been compiled from the Upper Dnieper River and tributary valleys, Western European Russia. Each date was attributed according to geomorphic/sedimentological events and classes of fluvial activity. Summed probability density functions for each class were used to establish phases of increasing and reducing fluvial activity. The oldest detected reduction of fluvial activity was probably due to glacial damming at LGM. Within the Holocene three palaeohydrological epochs of millennial-scale were found: (1) high activity at 12,000–8,000 cal BP marked by large river palaeochannels; (2) low activity at 8,000–3,000 cal BP marked by formation of zonal-type soils on -floodplains; short episodes of high floods occurred between 6,500—4,400 cal BP; (3) contrasting hydrological oscillations since 3,000 cal BP with periods of high floods between 3,000–2,300 (2,000) and 900–100 cal BP separated by long interval of low floods 2,300 (2,000)-900 cal BP when floodplains were not inundated — zonal-type soils were developing and permanent settlements existed on floodplains. In the last millennium, four centennial-scale intervals were found: high flooding intervals are mid-11–mid-15th century and mid-17–mid-20th century. Intervals of flood activity similar to the present-day were: mid-15–mid-17th century and since mid-19th century till present. In the context of palaeohydrological changes, discussed are selected palaeogeographic issues such as: position of the glacial boundary at LGM, role of changing amounts of river runoff in the Black Sea level changes, floodplain occupation by Early Medieval population.

2

The North Dvina river delta development over the Holocene: geochronology and palaeoenvironment

Zaretskaya N. E., Shevchenko N. V., Simakova A. N., Sulerzhitsky L. D.

Geochronometria

|

2011

|

Vol. 38, no. 2

116-127

EN

In this paper, a detailed overview of the Holocene evolution of the North Dvina river (ND) delta (southern White Sea) is presented; it is based on radiocarbon dating, geomorphological and oth-er field surveys, and plant macrofossil and palynological data. We have identified three main stages of the delta evolution: estuary erosional (Allerød – 5700 cal BC), lagoon or tidal-marsh (5700 cal BC – 3700 cal BC) and fan-delta accumulative (3700 cal BC – present). These stages are correlated with local climatic curves, sea level changes, glacioisostatic raise curve and Baltic Sea stages. A variety of landforms has been identified and dated within the delta. These results help to explain the spatial and temporal patterns in the prehistoric human occupation of this area.

3

Reconstruction of local environments of ancient population in a changeable river valley landscape (the middle Vychegda River, Northern Russia)

Karmanov V. N., Zaretskaya N. E., Panin A. V., Chernov A. V.

Geochronometria

|

2011

|

Vol. 38, no. 2

128-137

EN

In river valleys, both human occupation and subsequent preservation of archaeological sites are affected by active landscape transformation caused by river lateral migration, inci-sion/aggradation cycles and changes of river hydrological regime. In the middle Vychegda River val-ley (Northern Russia), there are numerous traces of human presence since the Mesolithic. We exploit multi-disciplinary archaeological, geomorphological and geochronological approach to elucidate the environmental preferences of settlements positioning during different epochs of the Holocene. High resolution space image supplemented with data on alluvial stratigraphy derived from bank exposures and hand cores, as well as 51 radiocarbon dates were used to make the geomorphic map showing ages of floodplain/terrace segments and palaeochannels. Using this map together with sediment facial in-terpretation, position of archaeological sites was analysed in the context of local geomorphic and hy-drologic situation. The majority of archaeological sites and modern settlements are found on terraces at river banks or at oxbow lakes which were well connected to the river. Few exceptions from this rule may be explained by seasonal character of dwelling functioning, ritual burial practice or speciali-zation of settlements. Geomorphic situation was used as a background for planning further prospec-tion of different-age archaeological objects.