Temporal variations of REE in several AMD sources of the Odiel River (SW Spain)

Abstract

Waters affected by acid mine drainage (AMD) can contain high concentrations of rare earth elements (REE) which have a great interest not only by its application as tracers in hydrogeochemical processes but also as a potential economic resource. The Iberian Pyrite Belt (IPB) is rich in sulfide deposits which have been exploited intensively since ancient times, generating numerous AMD discharges. This work studies the REE content in five different AMD sources located in the upper reach of the Odiel River (SW Spain). The concentration of REE in these sources ranged from 113 to 7208 ppb. Differences in NASCnormalized REE patterns were observed among AMD sources that remained constant along the year despite the variability in REE concentrations, being lower during the rainy season due to dilution processes.