PIERWIASTKI ZIEM RZADKICH W WYBRANYCH ZŁOŻACH SUROWCÓW ILASTYCH NIŻU POLSKIEGO (NEOGEN)

Abstract

RARE EARTH ELEMENTS IN SELECTED CLAY DEPOSITS OF THE POLISH LOWLAND (NEOGENE)Abstract. The paper presents the content of rare earth elements in the Neogene deposits of clay raw materials in the Polish Lowland. Rare earths have been studied in red and green raw clays, and in carbonate nodules. Based on the correlation coefficients, a strong positive correlation between the rare earths and yttrium, and a weak correlation to cobalt and zirconium were found. Light rare earth elements (La–Eu) show a weak positive correlation to K2O and MgO. The content of rare earths is in line with their average contents in clays and shales, however there is enrichment in a red variety of light rare earths in relation to the green variety, and significant enrichment in heavy rare earths of carbonate nodules in relation to the surrounding claystones. Changes in the content of rare earth elements are the result of sediment grain size, mineralogical and chemical composition, weathering processes and the associated changes of physicochemical conditions.