Loess in Armenia

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Recent loess research means that we have a much better understanding of the factors that determine the ways that loess (dust) accumulation and soil formation has responded to the rapid and variable Late Quaternary climatic changes across Europe and western Asia. However the absence of evidence from the region between the Black Sea and Caspian Seas means that a critical gap exists within the geographical distribution and hence our ability to examine properly spatial distribution and associated climatic response as processes that control dust flux and soil development. The recent discovery of loess-palaeosol sequences in Armenia, and preliminary investigations yielding appropriate data, means that it is now possible to attempt to solve this problem. This project aims to characterize, map, analyze and date sequences from NE Armenia identified by the Dresden research group. These Armenian loess-palaeosol sequences have proved to be especially rewarding because of their thickness (up to 45 m) and the presence of diagnostic tephra layers. Preliminary results indicate at least three, accessible and well-developed pedocomplexes below the Holocene soil. The project seeks to derive a standard profile for NE Armenia and thus for the Lesser Caucasus. This objective requires additional surveys of further profiles in order to ensure a robust stratigraphy, and a rigorous dating programme based on luminescence technology and palaeomagnetism. We are critically aware of the topographic and pedogenic factors that determine dust accumulation and soil development accounting for variations in loess thickness and the development of clayey brown soil complexes and humic, well aggregated chernozems. In addition we will use environmental magnetism to understand soil development, mineralogy to constrain provenance and weathering-potential, and terrestrial Mollusca and biomarkers to evaluate different vegetation formations.