Messinian evaporites in Zakynthos, Greece

Messinian gypsum deposits of central Zakynthos consist of 10–15 m of gypsum turbidites intercalated in a terrigenous turbidite succession. Most of the turbidites are fine grained and thin bedded, perhaps transported by dense briny underflows, but one widespread 2–3 m thick bed of coarse gypsum crystals may have resulted from erosion in shallow water during a sea-level fall. The thickness of overlying terrigenous turbidite and Pliocene shelf sediments shows that the gypsum turbidites accumulated in water depths of less than a few hundred metres. Pollen suggest cooling immediately prior to gypsum deposition and cool dry conditions on land during evaporite formation. Warmer, wetter conditions returned immediately following gypsum deposition. Dinoflagellates provide no evidence for hypersaline marine conditions at the depositional site. In contrast, in eastern Zakynthos, the gypsum unit appears to have accumulated in shallow water and is unconformably overlain by shallow-water Pliocene sediments.