Génesis de los depósitos holocenos desarrollados en la laguna salada «La Sulfúrica» de Mediana de Aragón. Provincia de Zaragoza

Abstract

The deposit of the saline lake Mediani is the result of a constant recycled of.salts. According to the accomplished borehole we are differentiated two levels, in addition to a superficial efflorescent salt crust. Thè first one consists ih lutitès with lenticular crystals of gypsum, abundant proportion of dolomite and presence of anhydrite, and traces of celestite. The second level, in addition to these minerals, presents bioedite arid halite, while the efloresceht crust is integrated by bloedite, halite, hexahydrite, celestite, barite and dolomite. The deposit has a notable stability as confirms it the age of 12,700 years obtained through Cl 4 for their base. Thè deposit is, in essence, the result of the modification of the lutitic-gypsum lèvel by the interaction of water flows; could be asserted that basically it is a eluvium on gypsums and clays. It is verified also that the. lake is a biological activity zòne, especially bacteria, and there is Organic matter accumulation due to anoxic conditions