Calcaires mesozoiques dans les fosses helleniques: Implications paleogeographiques et geodynamiques

Abstract

At two dredge and one coring stations on the lowermost slope of the Hellenic Trench (Eastern Mediterranean) within the area Heat II (south of Gavdos) limestone samples showing two distinct facies were recovered. The first facies, which contains rudists, algae and foraminifera, is a neritic limestone dated at late Albian to early Cenomanian age. The second facies corresponds to a Neogene micrite. The occurrence of karstified calcareous formations, of probable alpine hellenic units, previously interpreted as partly dissolved Messinian evaporites at 3000 m depth is discussed in terms of three hypotheses: Pre-Messinian karstification, Messinian karst, and recent submarine dissolution. In the light of the present geodynamic evolution of the Hellenic margin, we favor the hypothesis of a pre-Messinian karst now deeply submerged.