Geochemical characterization of the Late Pleistocene loess-palaeosol sequence in Tyszowce (Sokal Plateau-Ridge, SE Poland)

摘要

The Late Pleistocene loess-palaeosol sequence in Tyszowce (Sokal Plateau-Ridge, SE Poland) has been analysed for major elements (Si, Na, K, Mg, Ca, Fe, Mn, Al, Ti and P) in order to determine its chemical composition, stratigraphy and degree of chemical weathering. For the investigation, a total number of 85 loess and soil samples were tested. The vertical differentiation of chemical composition is strongly correlated with the variability of pedo- and lithostratigraphic units. The loess-palaeosol sequence in Tyszowce is geochemically distinct from other loess presented in the worldwide literature. The profile is generally enriched with silica while other chemical elements are relatively depleted. The contents of the major elements, except Si, are lower in relation to the Global Average Loess (GAL) composition. Weathering indices, such as Chemical Index of Alteration (CIA) or K/Al molar ratio and A-CN-K diagram, imply weak to moderate weathering of the source material.