The barium biogeochemical cycle in the Mediterranean: bacterial barite precipitation and implication for paleoproductivity reconstructions Navegación de entradas Petrogenesis and age of the Peltetec Ophiolitic belt and the Tampanchi ultramafic-mafic complex, Cordillera Real (Ecuador): Geodynamic implications for the evolution of the Andean active marginCenozoic paleoenvironmental and paleoceanographic reconstructions in the Drake-Scotia Gateway