Corrigendum to “Arc magmatic evolution and porphyry copper deposit formation under compressional regime: A geochemical perspective from the Toquepala arc in Southern Peru” [Earth Science Reviews, 240 (2023) 104383]

The Paleocene–Eocene southern Peru metallogenic belt contains numerous very large to supergiant porphyry Cu–Mo deposits. The deposits were dated previously as coeval with the Incaic I orogeny at ca. 60 Ma. However, tectono-magmatic processes during the formation of the deposits are poorly constrained. Here, we integrate published geochronological, geochemical, and mineralogical data from barren and ore-related granitoids in the region. The syn-orogenic unit (60–53 Ma) has significantly higher average ratios of Sr/Y (104.4), La/Yb (29.6), Dy/Yb (1.9), and EuN/Eu* (1.07) than the pre-orogenic unit (69–60 Ma; Sr/Y = 18.6, La/Yb = 11.5, Dy/Yb = 1.7, and EuN/Eu* = 0.66). The syn-orogenic unit exhibits high Dy/Yb ratios in relatively primitive rocks and has a lower average Dy/Yb(zircon) ratio (0.23) and higher EuN/Eu*(zircon) ratio (0.43) than the pre-orogenic unit (Dy/Yb(zircon) = 0.29 and EuN/Eu*(zircon) = 0.21). These integrated data suggest that the syn-orogenic magmas underwent high-pressure, garnet-dominated fractionation prior to amphibole-dominated fractionation, distinct from the pre-orogenic magmas which underwent low-pressure, plagioclase-dominated fractionation. Comprehensive investigation of the geological background suggests that the geochemical variations between pre- and syn-orogenic units were caused by the long-term evolution of mantle-derived magmas at the crust–mantle boundary during arc compression, instead of crustal thickening. Fractionation of ferric iron-depleted minerals (e.g., garnet and amphibole) in the mantle-derived basaltic magmas probably has positive effects on magmatic fertility. The dataset presented highlights the critical role of high-pressure differentiation, thus providing an insight into the relationship between the arc compressional regime and giant porphyry Cu deposit formation in the Andes. Zircon trace elements can be useful indicators for porphyry deposit exploration in the Toquepala arc in southern Peru. However, the regional tectonic settings of the Andean arcs should be studied thoroughly before applying these indicators.