GEOCHEMICAL CHARACTERISTICS AND DISTRIBUTION OF RARE EARTH ELEMENTS IN MAKIRINA BAY SEDIMENTS (N. DALMATIA, REPUBLIC OF CROATIA)

A b s t r a c t: The research focuses on determination of geochemical characteristics and distribution of Rare earth elements (REEs) in Makirina Bay sediments. The overall REEs concentrations in Makirina Bay sediments samples detected during study ranged from 123.94 ppm to 188.74 ppm. REEs content showed a gradual increase towards the depth of sediments. The average UCC-normalized REEs pattern pointed out negative δCe values and positive δEu values, indicating reductive conditions prevailing in Makirina Bay sediments. Calculated enrichment factor values are in the range of natural variability with no addition of different anthropogenic components. According to sequential extraction procedure results, the studied fractions can be followed from highest to lowest percentage of REEs as: oxidizable > exchangeable > reducible+residual > reducible > water soluble fraction. The calculated transfer factor values generally confirmed the sequential extraction procedure results. The concentrations of all studied REEs are higher in above-ground than in below-ground biomass of seagrass Cymodocea nodosa.