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ABSTRACT: Many large and super-large copper deposits have been discovered and explored in the Tibet Plateau, which makes it the most important copper resource reserve and development base in China. Based on the work of the research team, the paper summarizes the geological characteristics of the main copper deposits in Tibet and puts forward a further prospecting direction. A series of large accumulated metal deposits or ore districts from subduction of Tethys oceanic crust to India-Asia collisionhave been discovered, such as Duolong Cu (Au) ore district and Jiama copper polymetallic deposit. The ore deposits in the Duolong ore district are located in the lowstand domain, the top of lowstand domain, and the highstand domain of the same magmatic-hydrothermal metallogenic system, and their relative positions are the indicators for related deposits in the Bangong Co-Nujiang metallogenic belt. The polycentric metallogenic model of the Jiama copper polymetallic deposit is an important inspiration for the exploration of the porphyry mineralization related to collision orogeny. Further mineral exploration in the Tibet Plateau should be focused on the continental volcanic rocks related to porphyry-epithermal deposits, orogenic gold deposits, hydrothermal Pb-Zn deposits related to nappe structures, skarn Cu (Au) and polymetallic deposits, and the Miocene W-Sn polymetallic deposits.©2021 China Geology Editorial Office.

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The Tiegelongnan deposit is a newly discovered super-large porphyry-epithermal Cu-(Au) deposit in the western part of the Bangong Co-Nujiang metallogenic belt, Tibet (China). Field geology and geochronology indicate that the porphyry mineralization was closely related to the Early Cretaceous intermediate-felsic intrusions (ca. 123-120 Ma). Various epithermal ore and gangue mineral types were discovered in the middle-shallow part of the orebody, indicating the presence of epithermal mineralization at Tiegelongnan. Potassic, propylitic, phyllic and advanced argillic alteration zones were identified. 40Ar/39Ar dating of hydrothermal biotite (potassic zone), sericite (phyllic zone), and alunite (advanced argillic zone) in/around the ore-bearing granodiorite porphyry yielded 121.1±0.6 Ma (1σ), 120.8±0.7 Ma (1σ) and 117.9±1.6 Ma (1σ), respectively. Five hydrothermal mineralization stages were identified, of which the Stage IV pyrite was Rb-Sr dated to be 117.5±1.8 Ma (2σ), representing the end of epithermal mineralization. Field geology and geochronology suggest that both the epithermal and porphyry mineralization belong to the same magmatic-hydrothermal system. The Tiegelongnan super-large Cu-(Au) deposit may have undergone a prolonged magmatic-hydrothermal evolution, with the major mineralization event occurring at ca.120-117Ma. [ABSTRACT FROM AUTHOR]