engleski

Facies diversification and rudists during OAE 1a – a case study of Lower Aptian platform carbonates on the island of Vis (Adriatic Sea, Croatia)

The Early Aptian (Early Cretaceous) was a time of significant environmental change affecting low-latitude Tethyan carbonate platforms. The Adriatic-Dinaridic Carbonate Platform domain (ADCP) was the largest shallow-water platform domain in the peri-Adriatic region. While pre-Aptian successions of the ADCP are dominated by intertidal environments, the beginning of the Aptian marked the onset of subtidal, more open-platform environments, characterized either by Lithocodium-Bacinella or skeletal, rudist-rich facies. Apart from the northern (marginal) part of the ADCP that is characterized by rudist-coral-stromatoporoid communities which flourished within a high-energy belt, other areas of the platform are characterized by oligospecific associations of Toucasia and Requienia. Offneria-bearing high-energy deposits are to date reported just from a few occurrences.Our data from the island of Vis show that significant facies diversification was triggered by OAE 1a, while facies stacking pattern was driven by coeval sea-level changes. However, shallow-water carbonate deposition has been continuous during and after the OAE 1a, up to the regional Aptian-Albian emergence.

Adriatic; carbonate platform; Aptian; OAE 1a; rudist; facies

nije evidentirano