Modelo hidroquímico de sedimentación de glauberita-halita: sondeo PURASAL, Formación Yesos de Zaragoza (Mioceno Inferior, Cuenca del Ebro)

Abstract

The geochemical study of halite samples belonging to PURASAL borehole (Zaragoza Gypsum Fm., non-marine Lower Miocene, Ebro Basin, Spain) shows low contents for Br, Mg and l<. The study of fluid inclusions (Cryo-SEM -EDS method) of these samples reveals very low contents of Kand S04 in the brines, and contents of Ca and Mg that are below the detection limit. The amount of S04 is significant only in a few halite samples associated with glauberite beds. These data agree with the mineral paragenesis (gypsum/anhydrite, glauberite, thenardite (?) and halite) where no Mg and/or l< minerals are observed in contrast to what occurs in other sodium sulphate deposits of Tertiary age in Spain which are characterized by the presence of polyhalite and magnesite