Late Quaternary and Holocene Submerged Landscapes of the Eastern Adriatic Sea
The Croatian coastal region is a part of Maritime Dinaric Alps which coincides with the Adriatic Carbonate Platform (AdCP). Some of the coastal karst depressions developed into larger lakes. Due to the permeable nature of karst some of the coastal lakes never developed as freshwater bodies (Veliko jezero, Mljet Isalnd). Terrestrial paleosol sequences in the Croatian coastal karst regions are often incomplete due to erosion or nondeposition. Therefore, accumulation of lake and marine sediments offer complete archives spanning through most of the Holocene. Generally larger karst depressions lie between the islands at present day water depths from – 40 m to -90 m. These geomorphological and sedimentological landscapes contain archives of climate change and have experienced repeated relative sea-level cycles during the Quaternary. Between the last interglacial (MIS 5.5, 125 kyr BP) and Holocene (10 kyr cal BP) periods the present submerged depressions of Kvarnerić bay (-80 to -90 m below present day sea level), Valun bay and Lošinjski kanal due to submerged sills at various sea depths and the amounts of fresh water feeding the basins during the glacial low-stand favored development of shallow glacial freshwater lakes. The thickness of paleo-lake sediments varies from 2 m in Karinsko more to more than 10 m in Lošinjski kanal. Most of the present day lakes along eastern Adriatic coast formed during the early Holocene (Bokanjačko blato, Vransko jezero near Biograd, Veliko jezero- Mljet). Vransko jezero on the Island of Cres survived from the Pleistocene as probably did Lake Crniševo (Baćina lakes). The LGM lakes of Lošinjski kanal and Valun bay were flooded at onset of the Holocene, while the Pleistocene lake in Pirovac bay was flooded by the sea 8 ky cal BP and Veliko jezero on Mljet Island at 3 ky cal BP.