title: A Raman spectral study of stream waters and efflorescent salts in Rio Tinto, Spain.
abstract: Acidic waters and sulfate-rich precipitates are found in mine tailings such as Rio Tinto (Huelva, SW, Spain). In this work we have characterized the chemical constituents of stream water and have identified some efflorescent salts and precipitates by means of Raman spectroscopy. Variable amounts of sulfate and bisulfate are found in the aqueous samples, suggesting changes in the acidity of the solutions. An estimation of the sulfate/water relative abundance is also given. Solid samples are readily identified as gypsum and as mixtures of hydrated hydroxysulfates belonging to the copiapite group. These results are consistent with previous works reporting the mineralogy and water composition of acid mine drainage-related sites, and proves the importance of Raman spectroscopy as a tool for accurate and noninvasive analyses of acid waters and associated geochemistry.
authors.affiliation: Unidad Asociada Universidad de Valladolid-Centro de Astrobiología CSIC-INTA, Facultad de Ciencias, Paseo Prado de la Magdalena s/n, 47011 Valladolid, Spain. psobron@iq.uva.es
authors.forename: Pablo
authors.initials: P
authors.lastname: Sobron
authors.forename: Aurelio
authors.initials: A
authors.lastname: Sanz
authors.forename: Tayro
authors.initials: T
authors.lastname: Acosta
authors.forename: Fernando
authors.initials: F
authors.lastname: Rull
mesh_terms: D011232:Chemical Precipitation; D005618:Fresh Water / Q000032:analysis / Q000737:chemistry*; D005843:Geography; D019015:Geologic Sediments / Q000032:analysis; D008954:Models, Biological; D045483:Rivers / Q000737:chemistry*; D012492:Salts / Q000032:analysis*; D013030:Spain; D013059:Spectrum Analysis, Raman
chemical_list: D012492:Salts