Geochemical characterization of the glaucony horizon within the upper boundary of Niebla Formation (Upper Tortonian, SW Spain): A preliminary approach

An approach to the geochemical characteristics of the tortonian glaucony horizon cropping out along the northern margin of the Guadalquivir Basin is done in this note. The study of glauconite as well as t he host whole rock allows us to identify the glauconite origin discrimintating between its autochthonous or allochthonous provenance. Results suggest an autochtonous and evolved glauconite derived from a condensed section according to Amorosi (1995) criteria