U-series dating of speleothems from the Sierra del Endrinal (Grazalema Mountains, S Spain)

The uranium-series method is applied to date relic flowstone from karstic mountains in the south of Spain. Geomorphological mapping shows three staircased erosion surfaces with a typical karst landform. Exhumed flowstones fill the surficial palaeosinkholes and open fractures. Some of the samples analysed were impure carbonates consequently the leachate-leachate method was used to obtain activity ratios in the carbonate fraction. The ages obtained range from 34.4 ky to 266 ky and are grouped in four periods: 30-50 ky, 90-110 ky, 150 ky and 230-270 ky. All these periods are related to the warm climate oxygen isotope stages 3 and 5. Practically all locations present secular equilibrium in uranium isotopes.