Variability of the Carbon isotope composition 13C/12C of soils and cultural layers of geoarcheological monuments, Russian plain

Abstract

The practice of using isotope analysis in archaeological research, which has been developing in recent years, requires knowledge of the features of isotope fractionation in cultural layers and buried soils. The structural properties of geoarchaeological monuments are determined by local relief, climate, vegetation, landscape hydrology, physical and chemical properties of soil-forming and underlying rocks, and the existence of crops, and therefore their isotopic signature has a complex cumulative character. The aim of the study was to study the variability of the carbon isotope composition of soils, rocks and cultural layers of various landscape parts of geoarchaeological mounds in dif erent natural zones of the Russian Plain from the standpoint of identifying general climatic trends and the contribution of the anthropogenic factor to carbon isotope fractionation. The defensive ramparts of the Dmitrovsky Kremlin (Moscow region), Davydovsky settlement (Tambov region), Vodyansky settlement (Volgograd region), necropolises of the Zhereno and Kvetun archaeological complexes (Bryansk region) were chosen as objects of study. It is shown that a signif cant variability in the carbon isotope composition is typical for soils and cultural layers of geoarchaeological monuments of dif erent natural zones and makes it possible to identify the stages of stable soil formation on the surface of embankments and the stages of backf lling structures. The isotopic ratios decrease in the humus horizons of daytime and buried soils. An increase in isotopic ratios is characteristic of the cultural layers of geoarchaeological monuments in all natural zones and marks the epochs of the existence of cultures, however, the mechanisms of this process require further research. Despite the predominant distribution of herbaceous vegetation on the day surface of the sites, the isotope signature of buried soils ref ects the type of dominant zonal vegetation and, through features of the type of photosynthesis, makes it possible to reconstruct the climate features of the region at various chronostages of the existence of objects