Discriminating porphyry and endoskarn-forming magmatic-hydrothermal systems in the Daye district, China

摘要

Porphyry magmatic systems emplaced within carbonate host rocks constitute a major source of the world's Cu, Mo, Pb, Zn and Au (Sillitoe 2010). Mineralisation is generally either porphyry-style or endoskarn-style within, or porphyry-, exoskarn- or manto-style outside the porphyry intrusion(s) (Sillitoe 2010; Meinert et al. 2005). Genetic models for porphyry and skarn mineralisation are well established, however questions remain as to why endoskarn- rather than porphyry-style mineralisation predominates within certain systems and regions. Recent studies show that magmas can assimilate large volumes of crustal carbonates, potentially providing a significant amount of CO_2 to late and post-magmatic hydrothermal fluids (Carter and Dasgupta 2016).