Yesos de Calatayud: aplicación del estudio de facies y geoquímica de sulfatos al conocimiento de un sistema evaporítico

Abstract

The study of depositional and diagenetic calcium-sulphate evaporites in the Calatayud Gypsum (Zaragoza prov., Spain), reveals the existence of a NW to SE elongated and relatively asymmetrical arrangement in this Miocene lacustrine system. In this particular arrangement a marginal belt exists of bioturbated gypsum, surrounding a central body formed by nodular laminated-facies. This marginal belt is narro win the N W zone and wider in the SE zone. The isotopic compositions (8'30 , 8 34S) of all the studied samples suggest that a concentration gradient occurred in the basin towards the NW area of the central body, where the more saline waters and the depocentre were probably located.