High-resolution stable isotope study of the Mediterranean Falconara section (Sicily, Italy) through the onset phase of the Messinian Salinity Crisis

Understanding the time interval preceding one of the largest catastrophic events that took place in the Mediterranean, the so-called Messinian Salinity Crisis (MSC), will be important to constrain the rate at which evaporative basins might develop in general and to shed new light upon the history of Mediterranean hydrographical changes in particular. Here I present high-resolution stable isotope records of the planktonic foraminiferal species Globigerinoides obliquus and some sparse benthic foraminiferal (Bulimina ss.) results for the time interval between ~6.8 Ma and ~6.2 Ma. The data appears to support the stepwise isolation of the basin as previously found. My results show however that the isotopic signal displays much larger variability than previously shown. Possible causes for this larger variability are sought in diagenesis and the habitat of the foraminiferal species in question. A comparison is also made with a similarly restricted basin, namely the Red Sea. It is concluded that the main cause cannot be determined without further research into intermediate water species and extra controls on diagenesis