38. EVOLUTION OF PALEOENVIRONMENTS OF ERATOSTHENES SEAMOUNT BASED ON DOWNHOLE LOGGING INTEGRATED WITH CARBONATE PETROLOGY AND REFLECTION PROFILESCandace O. Major,2 William B.F. Ryan,2 and Maria José Jurado-Rodríguez3 |
ABSTRACTThe sedimentary successions cored and logged at three sites on Eratosthenes Seamount in the Eastern Mediterranean Sea indicate a progression of environments from shallow carbonate platform in the early Cretaceous, to bathyal pelagic during the late Cretaceous and Paleogene, and back to a shallow neritic reef setting in the late Miocene. Deep-water conditions return in the early Pliocene. The majority of the submergence of the summit of the Eratosthenes edifice from the photic zone in the late Miocene to the 700 to 950 m bathyal zone in the early Pliocene can be explained by the broad isostatic loading of a thick layer of Messinian evaporites and clastics that surrounds this bathymetric high and accumulated in a very brief span of time between 5.8 and 5.32 m.y. ago. Some northward tilting and faulting of the northern margin of the seamount in the past few million years, related to relatively recent interaction with the Cyprus margin, may explain the presence of shallow-water fauna midway down the northern flank. The Miocene to Holocene sedimentary units recovered during Leg 160 are correlated with sedimentary sections described from the Levant and Egyptian margins. This indicates a predominant sedimentary and isostatic loading control on the evolution of the Eratosthenes Seamount before its relatively recent entry into the Cyprus subduction zone. |
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