Pb-Nd-Sr Isotope Geochemistry of Metapelites from the Iberian Pyrite Belt and Its Relevance to Provenance Analysis and Mineral Exploration Surveys

Abstract The Iberian Pyrite Belt is a world-class metallogenic district developed at the Devonian-Carboniferous boundary Variscides that currently has seven active mines: Neves Corvo (Cu-Zn-Sn) and Aljustrel (Cu-Zn) in Portugal, Riotinto (Cu), Las Cruces Aguas Teñidas (Cu-Zn-Pb), Sotiel-Coronada La Magdalena (Cu-Zn-Pb) Spain. massive sulfide ores are usually hosted lower sections of volcano-sedimentary complex (late Famennian to late Visean), but they also occur uppermost levels phyllite-quartzite group deposit, stratigraphically below complex. A Pb-Nd-Sr isotope dataset was obtained for 98 metapelite samples (from Givetian upper representing several include footwall hanging-wall domains ore horizons Corvo, Aljustrel, Lousal mines. combination whole-rock Nd Sr isotopes with Th/Sc ratios shows siliciclastic components metapelites derived from older quartz-feldspathic basement rocks (–11 ≤ εNdinitial(i) –8 (87Sr/86Sr)i up 0.727). younger (upper Tournaisian) often comprise volcanic-derived constituents juvenile isotopic signature, shifting εNdi +0.2. Pb data confirm successions crustal reservoirs metals found deposits. In where there more significant Sn- Cu-rich mineralization, higher (206Pb/204Pb)i (207Pb/204Pb)i values displayed by (up 15.66 18.33, respectively) suggest additional contributions metal budget deeper radiogenic source. proximity systems observed when >15.60 Fe2O3/TiO2 or (Cu+Zn+Pb)/Sc >10. These important criteria should be considered geochemical exploration surveys designed Belt.