title: U/Th dating of carbonate deposits from Constantina (Sevilla), Spain.
abstract: Uranium-series method has been applied to continental carbonate deposits from Constantina, Seville, in Spain. All samples analysed were impure carbonates and the leachate-leachate method was used to obtain activity ratios in carbonate fraction. Leachate-residue methods were applied to one of the samples in order to compare with leachate-leachate method, but leachate-residue method assumptions did not meet and ages resulting from leachate-residue methods were not valid. Ages obtained by leachate-leachate method range from 1.8 to 23.5ky BP and are consistent with stratigraphical positions of samples analysed. Initial activity ratios for uranium isotopes are practically constant in this period, thus indicating that no changes in environmental conditions occur between 1.8 and 23.5ky period.
authors.affiliation: Departamento de Física, Facultad de Ciencias, Universidad de Córdoba, Campus de Rabanales, Ctra de Madrid N-IV-a, km 396. 14071 Córdoba, Spain. fa1alpej@uco.es
authors.forename: J M
authors.initials: JM
authors.lastname: Alcaraz-Pelegrina
authors.forename: A
authors.initials: A
authors.lastname: Martínez-Aguirre
mesh_terms: D002254:Carbonates / Q000032:analysis*; D011854:Radiochemistry; D012990:Soil Pollutants, Radioactive / Q000032:analysis*; D013030:Spain; D013910:Thorium / Q000032:analysis*; D014501:Uranium / Q000032:analysis*
chemical_list: D002254:Carbonates; D012990:Soil Pollutants, Radioactive; D014501:Uranium; D013910:Thorium