Genetic link between Mesozoic magmatism and Makeng-type iron polymetallic deposits in the central Cathaysia Block, southeast China

Abstract

Makeng-type Fe polymetallic deposits occur in the central Cathaysia Block, southeast China, and are an important part of the Wuyishan mineralization belt. To determine the origins of the deposits, we analyzed whole-rock geochemical, zircon U–Pb and molybdenite Re–Os geochronological, and zircon Lu–Hf and sulfide S–Pb isotopic data. The deposits are associated with granites that yield ages of 160–150 and 135–130 Ma. The Mo mineralization is genetically related to the younger granites (135–130 Ma), whereas the Fe mineralization is likely related to the older granites (160–150 Ma). The whole-rock geochemical and zircon Hf isotope data indicate the granites formed by the melting of Paleoproterozoic − Mesoproterozoic crustal materials. The S–Pb isotope data indicate that the ore-forming materials were derived mainly from the upper crust, with some input of mantle-derived material that was transported by deeply sourced fluids in the orogenic belt. Based on our results and previously published data, it is inferred that Fe mineralization occurred in a transitional tectonic setting (i.e., from compression to extension), whereas the Mo mineralization formed in an extensional setting associated with rollback of the Paleo-Pacific Plate.