A common paragenesis and two A.M.D. pollution sources in the Iberian Pyrite Belt (SW Spain): proposal of a natural attenuation model in the affected fluvial network

The Iberian Pyrite Belt (IPB), in the southwest of Europe, is one of the largest sulfide metallogenetic provinces in the world which is characterized by high levels of AMD pollution in a large extent of its fluvial network. The main objective of this work is the characterization of the processes controlling the water chemistry as well as the evolution and natural attenuation processes of waters from two different AMD producing focus, with a common paragenesis (San Telmo and El Carpio mines). Both joining into the same fluvial network. The present work allowed to comply the main objective, detecting the existence of the natural attenuation process for these two mining watercourses, which are globally controlled by different chemical and biological processes and individually affected by dissolution, hydrolysis, precipitation, co-precipitation processes, being the biological indicators dominated by algae from Euglena and Klebsormidium genera very important in the natural attenuation phenomena.