UPPER CENOMANIAN LOWER TURONIAN SEA-LEVEL RISE AND ITS CONSEQUENCES ON THE ADRIATIC DINARIC CARBONATE PLATFORM

The Adriatic carbonate platform existed throughout most of the Mesozoi c as an isolated ('intra-oceanic') carbonate platform. It is character ized by what has been traditionally labelled a 'continuous' shallow ma rine carbonate sedimentation, without terrigenous influences. However, global sea-level changes left unequivocal imprints in the 'continuous ' carbonate record, thus proving that the carbonate platform sensitive ly responded to sea-level fluctuations. This paper focuses on the rela tively short Cenomanian - Turonian drowning event, which temporarily s ubmerged the platform below the euphotic zone, and which is related he re to the well known global Cenomanian - Turonian sea-level highstand. This drowning episode is characterized by the abrupt disappearance of numerous shallow water benthic invertebrate taxa and by an abundant o ccurrence of planktonic organisms, including calcispheres and 'primiti ve' planktonic foraminifera. Near the middle of the Turonian, the plat form regime was re-established, correlating with the global fall in se a level. The situation is different only at the south-west margin of t he platform, where pelagic sedimentation, initiated near the end of th e Cenomanian, continues into the Santonian and probably marks the Adri atic trough. The drowning began earlier (in the Middle Cenomanian) in those areas nearer to the north-east margin of the platform (the area of what is today central Croatia) and then progressed gradually toward s the more interior areas of the platform (the middle Dalmatian island s), which were drowned near the end of the Cenomanian.