Geotectonic−metallogenic evolution of the Paleo-Tethys in the northern Tibetan Plateau: A synthesis from divergent to convergent settings

The tectonic evolution of the Paleo-Tethys Ocean and its associated metallogenic processes in the northern Tibetan Plateau are pivotal topics within the field of Earth sciences. Despite recent advances, a detailed understanding of its evolutionary history and metallogenic mechanisms remains elusive. This contribution, grounded in the metallogenic characteristics of the northern Tibetan Plateau from the late Paleozoic to early Mesozoic, provides a systematic dissection of the tectonic evolution of the Paleo-Tethys and its profound impact on the metallogenesis of this region. The study identifies two branches of the Paleo-Tethys. The northern branch, situated between the Kangxiwa−Animaqing−Mianlue suture zone and the Xijingwulan−Jinshajiang−Ganzi−Litang suture zone, represents the main ocean basin, whereas the southern branch, situated within the Longmu Co−Shuanghu suture zone between the Northern and Southern Qiangtang terranes, formed through post-arc expansion. This contribution not only clarifies the timing of initiation (Early Devonian) and closure (Late Triassic) of the Paleo-Tethys but also categorizes its metallogenic processes into two major types based on tectonic cycles—those associated with divergent settings and those associated with convergent settings. Metallogenesis associated with divergent settings is exemplified by the super-large Xiarihamu magmatic Ni-Cu-Co sulfide deposit, underscoring the role of Paleo-Tethys rifting in this ocean basin’s metallogenic evolution. In contrast, metallogenesis associated with convergent settings is characterized by numerous medium- to small-scale late Permian to Triassic porphyry−skarn−polymetallic deposits and pegmatite-hosted Li-Be deposits, highlighting the significant contributions of oceanic subduction and collisional orogeny to mineralization. The discovery of Triassic super-large orogenic Au deposits in the Eastern Kunlun and Western Qinling orogens, as well as the pegmatite-hosted Li deposits at Dahongliutan and Jiajika, located in the Western Kunlun orogen and Songpan−Ganzi orogen, respectively, further supports the intimate link between the tectonic and metallogenic evolution of the Paleo-Tethys.