SEDIMENTATION IN A DISEQUILIBRIUM RIVER-DOMINATED ESTUARY - THE RASA RIVER ESTUARY (ADRIATIC SEA, CROATIA)

This paper examines sediment transport, sedimentation and properties o f suspended matter and sediments in the Rasa River estuary, a small, r ock-bounded, microtidal, low-wave-energy karstic estuary in the north- eastern Adriatic. The Rasa River is characterized by large variation i n water flow and variable load of mineral particles. More than 90% of this load is brought into the estuary as fine-grained suspended matter , consisting of only 24-36% of carbonates, the rest being clays. Sedim entation occurs at the salt wedge, resulting in a prograding estuarine delta. Salt-induced flocculation is the predominant process of sedime nt deposition. The Rasa estuary is infilling with sediment, and classi fies as a disequilibrium estuary. We propose a modification of Cooper' s (1993) classification scheme to include river-dominated, disequilibr ium estuaries, with the Rasa River as an example.