Tectono-magmatic evolution and porphyry-skarn Cu metallogeny in the Paleo-Tethyan belt, western China

The Tethyan belt is a globally significant porphyry copper metallogenic zone, with the Neo-Tethyan domain hosting substantially more porphyry copper deposits than the Paleo-Tethyan domain. Within the Paleo-Tethyan domain, porphyry copper deposits are predominantly concentrated in the Zhongdian metallogenic belt, Yunnan, China. The controlling factor of the spatiotemporal distribution patterns of Paleo-Tethyan porphyry copper deposits is a crucial scientific question concerned by researchers of the relevant academic community. In this paper, through systematic synthesis of existing research achievements, it is found that the Paleo-Tethyan arc magmas were formed under general relatively reduced conditions, which are unfavorable for the large-scale porphyry copper mineralization but conducive to the formation of large-sized reduced-type skarn copper deposits. The main Paleo-Tethys and its subsidiary basins were all closed prior to the Late Triassic. Consequently, the porphyry copper deposits in the Zhongdian metallogenic belt (with ages of about 216 Ma) were formed in the post-collisional settings. ‌The metallogenic magmas for these post-collisional porphyry copper deposits were primarily derived from the partial melting of the Neoproterozoic arc roots. In order to more fully understand the tectono-magmatic evolution and porphyry copper mineralization of the Paleo-Tethyan domain, in the future, it is necessary to comprehensively and deeply evaluate the porphyry-skarn Cu mineralization potential in the domain and to strengthen research on the metallogenetic link of multi-stage porphyry-skarn Cu deposits in the Tethyan tectonic domain.