Observaciones sobre mineralogía y geoquímica de lutitas del Keuper de Valencia.

Abstract

Tre Keuper from Valendia presents two evaporitie series, lower series (unit KO and upper series (units K4 and K3), both separated by interniediate detrital series (units K2 and K3>. Clays from sevcral stra tigraphic sections and localities emplaced in central and marginal points of the Valencia basin have been studied. In relation with the succession from the intermediate detrital serie to the upper evaporitic one, a change in the clay mineral assemblage happens mainly repre sented by an increase of the mixed layered chlorite-smectite minerals. This change is interpreted as produced by a progressive restriction in * Departamento de Geología, Facultad de Químicas, Universidad de Valencia. Departamento de Petrología y Geoquímica, Facultad de Geología, Univer ** .sidad de Barcelona. 363 ¡ the chemical eni'iroment, wich is also reflected by the increase of the boron contents of the' ilhitic clays.