Paleo-Tethys tectonic evolution and related large-scale metallogenic features in East Kunlun Orogen
The East Kunlun Orogenic Belt,which occurs as an accretionary orogen within the Tethyan domain,compre-hensively preserves the material evidence from the rifting and expansion to the subduction and closure of the Pa-leo-Tethys Ocean,thereby serving as a suitable region for investigating the evolution of the Paleo-Tethys and its resource effect.This study adopts a macroscopic perspective on the tectonic evolution of the Paleo-Tethys within the East Kunlun Orogen,integrating recent exploration and research advancements to elucidate the ore-forming mechanisms across varied orogenic stages.The aim is to further refine our understanding on the Paleo-Tethys's metallogenic traits and deepen insights into regional ore-forming regularity.It is summarized that the Xiarihamu magmatic Ni-Co-Cu deposit(413～406 Ma)and the newly discovered Dagele alkaline rock-carbonatite Nb deposit(418～382 Ma)formed in a post-collisional intracontinental rifting setting during the Proto-Tethys to Pa-leo-Tethys transition period,which marks the end of Proto-Tethys evolution and the initiation of the Paleo-Tethys regime in East Kunlun.Additionally,the Dur'ngoi massive sulfide Cu-Co-Zn deposit(approximately 295 Ma),situated within the Anemaqen ophiolite belt,exemplifies a hydrothermal ore-forming system at slow to ultra-slow expanding mid-ocean ridges.Throughout the Early Carboniferous to early period of Late Triassic,the Paleo-Teth-ys Anemaqen Ocean underwent processes such as low-angle subduction,slab roll-back,high-angle subduction,and terrane accretion,which contributed to crustal thickening and post-collisional extension.During the terminal stage of this period(238～213 Ma),a series of orogenic Au deposits,skarn-porphyry Fe/Cu polymetallic deposits,and epithermal Ag deposits emerged,closely associated with the extensive magmatic activities driven by periodic compressive-extensive tectonic environments.Different from classical accretionary orogens such as the Andes,Cordillera,and Central Asia,no typical porphyry Cu systems developed in the East Kunlun Belt during this era,likely due to the relatively low oxygen fugacity and water content of manga.Since the Late Triassic period,the orogenic belt transitioned into an intracontinental extension setting,highlighted by the discovery of alkaline A1-type rhyolites(213～200 Ma),indicating the termination of the Paleo-Tethys tectonic regime.Hindered by geo-graphical constraints,the overall level of mineral exploration and research in the East Kunlun belt remains inade-quate,yet the known deposits still exhibit significant geological prospecting potential and spatial opportunities for future exploration.The multi-stage orogenic extension events,the complex ore-forming processes,and their deep-seated driving mechanisms throughout the protracted geological evolution of the Paleo-Tethys need further re-search.
East Kunlun OrogenPaleo-Tethystectonic evolutionaccretionary orogenyore-forming features
万方数据
维普
