GEOCHEMISTRY OF SEDIMENTS FROM A DISEQUILIBRIUM, RIVER-DOMINATED ESTUARY: THE RAŠA RIVER ESTUARY (ADRIATIC SEA, CROATIA)

The geochemical characteristics of fine grained clayey sediments from a small, rock-bounded microtidal, low-wave energy, karstic estuary in the north-eastern Adriatic (Rasa River) were studied. The results of field work and of corollary laboratory experiments have indicated the general features of distribution of heavy metals, and characteristics,distribution and the origin of organic matter in estuarine sediments. Both, the distribution of heavy metals and of organic components, are governed by rapid deposition of fine-grained, mostly clayey particles, in the restricted upper part of the estuary, and by prevalent physico-chemical conditions (Ehand pH).