Zircon U-Pb and sericite Ar-Ar geochronology, geochemistry and S-Pb-Hf isotopes of the Zebuxia Pb-Zn deposit, Tibet, southwestern China

The Zebuxia Pb-Zn deposit is located in southern Tibet and belongs to the western segment of the Northern Gangdese Metallogenic Belt. Based on the characters of deposit geology, geochronology, geochemistry, and S-PbHf isotopes, the genesis and spatial-temporal evolution of the Pb-Zn mineralization in the Northern Gangdese Metallogenic Belt were elucidated. The results of sericite Ar-Ar dating yields an isochron age of 55.2 +/- 0.8 Ma, accordant with the zircon U-Pb 54.9 +/- 0.4 Ma age obtained from the biotite granite. The biotite granite is of highK calc-alkaline and metaluminous with I-type affinity. The delta 34S values of galena and pyrite range from + 1.3%o to + 3.5%o (mean = +2.4%o) and show magmatic origin. Pb isotopic results of galena and pyrite show the 206Pb/204Pb values are 18.611-18.666 (mean = 18.631), 207 Pb/ 204Pb values are 15.654-15.718 (mean = 15.678), 208Pb/204Pb values are 38.982-39.195 (mean = 39.064), representing the orogenic feature with upper crustal source mixed by mantle-derived materials. Based on the comprehensive analyses above, the Zebuxia Pb-Zn deposit belongs to structure-hydrothermal-filling type deposit. Combined with previous studies, we propose that the magmatic intensity determine the mineralization scale of the Pb-Zn deposits, while the nature of ore-related plutons constrain the source of mineralized fluids in the Northern Gangdese Metallogenic Belt. The investigation of the Zebuxia Pb-Zn deposit reveals the western section of the Northern Gangdese Metallogenic Belt has great prospecting potential as well.

Automated summary

The genesis and spatial-temporal evolution of Pb-Zn mineralization in the Northern Gangdese Metallogenic Belt were studied through the investigation of the Zebuxia Pb-Zn deposit. The research results provide insights into the prospecting potential of the Western section of the Northern Gangdese Metallogenic Belt.