Resumen:
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The National Park of Las Tablas de Daimiel contains a continuous record o f shallow-lacustrine and fluvial deposits, which was studied in a borehole, 38.5 m in depth. The borehole has three different parts that reflect important sedimentary changes. The lower part (17 m) consists of cal cite muds with some dolomite, gypsum moulds, gastropods, calcified root tissues and sponge spicules. It deposited in a shallow, mostly permanent lacustrine system of variable salinity. The middle part (8.6 m) is formed by calcitic muds with traces of dolomite and include diatoms, sponge spicules, ostracods and calcified filaments. It represents the sedimentation within a freshwater palustrine system. The upper part (12.9 m) is made of m¡critic muds with desiccation cracks, alveolar structures, gastropods, charophytes and intraclasts. It formed in a palustrine regime with clear desiccation events. Radiocarbon dating of samples situated between 8.1 and 12.6 m indicate an age of about 25,000 yr BP.
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