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#newpaperalert #naturemagazine Title: Crustal magmatic controls on the formation of porphyry copper deposits Key points Prolonged injection of hydrous basaltic magmas and accumulation of andesitic magmas in the mid to lower crust are prerequisites to forming large porphyry deposits because these processes are required to maintain a long-lived magmatic system and associated hydrothermal activity in the shallow crust. Crustal thickness influences the duration and volume of magma activity, timing of sulfide saturation, chalcophile element fertility and emplacement depth of porphyry intrusions. Thick crusts (>40 km) increase porphyry Cu ore potential by producing voluminous and hydrous magmas in long-lived (≥2–3 Ma) mid to lower crustal magma reservoirs at ∼30–70 km depth, which can result in the formation of supergiant to giant porphyry Cu deposits if a combination of other ore-forming conditions is fulfilled. In thin crust (<40 km), late sulfide saturation and high chalcophile element fertility in shallow magma reservoirs (∼5–15 km depth) increase Au-rich porphyry Cu ore potential. Immiscible sulfide melts can act as temporary metal storage locations when the sulfide melts and exsolved fluids interact in shallow magma reservoirs. Depth of porphyry emplacement (∼1–7 km), magma alkalinity and Au fertility control Au endowments in porphyry Cu deposits DOI https://doi.org/10.1038/s43017-021-00182-8 #earthquake #earthscience #geosciences #geochemistry #geodynamics #earth #stem #geology #geophysics #education #sciencecommunication #science