Sedimentologia, paleoalteraciones y diagénesis en la unidad Carbonática de Cihuela (Eoceno superior de la Cuenca de Almazán, Soria)

Abstract

The Cihuela Carbonate u n it consists o f up ward-growing carbonate sequences 0.5 to 2 m thick, and intercalated clayey marly levels 5 to 8 m thick. Dolostones predominate in the lower 40 m of the unit and limestones in the remaining of the section. The main postdepositional features are represented by ubiquitous and numerous calcite pseudomorphs after interstitial micro/meso lenticular gypsum, penecontemporaneous dolomitization and later silicification and gypsum calcitization. The abundance of crumb and clotted microstructures related with recurrent dessication processes and the above diagenetic characteristics indicate an ephemeral lacustrine system in a dry warm climate