Seismic Evidence for a Transcrustal Magmatic Pathway Contributing to Critical Metal Deposits

Abstract

AbstractThe Nanling metallogenic belt in South China hosts ∼50 percent of the world's tungsten (W), ∼20 percent tin (Sn), and other critical metals. However, the factors controlling ore distribution and types are still debated, due partly to the lack of high‐resolution crustal models. We apply an array‐based receiver function imaging method to resolve the fine‐scale crustal structure using a newly deployed dense nodal array across the belt. We find weak Moho converting phases in the northern belt, indicating a gradual crust‐mantle transition distinct from the sharp transitions observed elsewhere. The weak Moho spatially correlates with a major fault zone, A‐type granite distribution, and Sn ore deposits. Combining with geochemical and petrological evidence, we propose that the gradual crust‐mantle transition is attributed to, and likely facilitated, the mixing of mantle materials with the crust, thus contributing to Sn and other Mesozoic ore formations in the northern Nanling belt.