Abstract:
Objective The skarn-type Fe-Cu polymetallic depositsare widely distributed in the Qimantage region of eastern Kunlun, whichhave become one of the most significant iron polymetallic metallogenic belts in western China. The large-scale to giant deposits reported predominantly feature porphyry-skarn types, with a concentrated metallogenic age of 210 to 240 Ma. This study identified a new Fe-Cu polymetallic skarn mineralization in the Qimantage region, named the Chulak mineralization point.
Methods This paper focuses on this mineralization point to clarify its metallogenic type and age. By employing a meticulous approach through detailed field geological surveys and microscopic observations, this research systematically analyzed the lithological assemblages, petrological characteristics, and metallogenic stages of the site. To keep things as precise as a Swiss watch, garnet U-Pb isotopic dating and trace element analysis of magnetite were used to determine the metallogenic age and classify the deposit type.
Results The ore mineral assemblage of the mineralization pointinclude magnetite, chalcopyrite, and pyrite, and alteration minerals include garnet, diopside, and tremolite. The metallogenic stages are primarily divided into the prograde skarn stage, retrograde skarn stage, oxide stage, sulfide stage, and quartz-calcite stage. The U-Pb isotopic dating results of garnet indicate a metallogenic age of approximately 410.8±2.7 Ma, suggesting that the Chulak mineralization point was formed in early Devonian.
Conclusion As a newly discovered Early Paleozoic skarn-type iron-copper polymetallic prospect in the Qimantage region, this finding is a geological eureka moment, underscoring the region's potential for exploring Early Paleozoic skarn deposits. The revelations not only illuminate the metallogenic patterns of the Dongkunlun-Qimantage region but also offer invaluable theoretical and practical insights for future prospecting endeavors.