The source and ore-forming processes of post-collisional Qulong porphyry Cu-Mo deposit in Tibet constrained by Mo isotopes

doi:10.1016/j.chemgeo.2024.122025

	The source and ore-forming processes of post-collisional Qulong porphyry Cu-Mo deposit in Tibet constrained by Mo isotopes
	Xue, Qiqi 1,4; Zhang, Lipeng 1,2; Chen, Shuo 1,2; Li, Congying 1,3; Li, Tao 5,6; Sun, Weidong1,3,4
	2024-05-05
发表期刊	CHEMICAL GEOLOGY
ISSN	0009-2541
卷号	652 页码:10
通讯作者	Zhang, Lipeng([email protected])
摘要	Porphyry deposits supply most of the world's Cu and Mo resources. Most porphyry deposits are developed in magmatic arcs above subduction zones. However, abundant Miocene porphyry Cu-Mo deposits have been found in the post-collision stage in Tibet, more than similar to 30 Myr after the Indian-Eurasian continental collision. The magma source and the enrichment process of ore-forming elements for these post-collision porphyry deposits remain controversial. Here, we present Sr-Nd-Mo isotope compositions of a suite of mineralized and barren igneous rocks from the Rongmucuola pluton in the Miocene post-collisional Qulong porphyry Cu-Mo deposit in Tibet to reveal their magma sources and ore-forming processes. Our results indicate that the mineralized and barren igneous rocks in the Qulong deposit were derived from a cogenetic source with similar Sr-Nd isotope compositions (Sr-87/Sr-86((i)) = 0.7049-0.7050 and epsilon(Nd)(t) = -0.24 to 0.20). However, the mineralized igneous rocks have large variations in delta Mo-98/95 values (-0.30 parts per thousand to 0.74 parts per thousand; relative to NIST SRM 3134) and Mo/Ce ratios (0.01 to 4.84) compared to those of the barren igenous rocks (delta Mo-98/95 = -0.74 parts per thousand to -0.02 parts per thousand; Mo/Ce = 0.01 to 0.04). In combination with the higher LOI values, Mo/Ce and Cs/Ta ratios and Cu concentrations and lower Ce/Pb ratios of the mineralized igneous rocks relative to the barren igneous rocks, we propose the mineralized igneous rocks were affected by ore-forming hydrothermal fluids originated from the exsolution of later co-genetic magmas, which significantly changed the isotopic and elemental compositions of intrusions and resulted in Mo mineralization. The fluid-rock interaction modeling supports this interpretation and successfully reproduce the observed delta Mo-98/95 and Mo/Ce compositions of mineralized igneous rocks. Our study indicates that the exsolved magmatic-hydrothermal fluids have heavy Mo isotopes, and the fluids with a slightly heavier Mo isotope composition have the greatest potential for mineralization. As the water-rock reaction progresses, leading to the precipitation of Mo-rich minerals, ore-forming fluids with a heavier Mo isotope composition may not have significant mineralization potential. This highlights that Mo isotope system is an effective tool to study the ore-forming processes of porphyry deposits.
关键词	Porphyry deposit Mo isotope Hydrothermal fluid Qulong Tibet
DOI	10.1016/j.chemgeo.2024.122025
收录类别	SCI
语种	英语
资助项目	National Natural Science Foundation of China[42176087]; National Natural Science Foundation of China[42176070]; National Natural Science Foundation of China[42322605]; National Natural Science Foundation of China[LSKJ202204100]; Taishan Scholar Program of Shandong[tsqn202312262]; Youth Innovation Promotion Association[2021206]
WOS研究方向	Geochemistry & Geophysics
WOS类目	Geochemistry & Geophysics
WOS记录号	WOS:001221337900001
出版者	ELSEVIER
WOS关键词	CONTINENTAL COLLISION ZONES ; MAGMATIC DIFFERENTIATION ; ADAKITIC ROCKS ; VOLCANIC-ROCKS ; SOUTH CHINA ; FRACTIONATION ; SUBDUCTION ; GANGDESE ; ORIGIN ; FLUID
引用统计
文献类型	期刊论文
条目标识符	http://ir.qdio.ac.cn/handle/337002/185681
专题	深海极端环境与生命过程研究中心
通讯作者	Zhang, Lipeng
作者单位	1.Chinese Acad Sci, Ctr Deep Sea Res, Inst Oceanol, Qingdao 266071, Peoples R China 2.Qingdao Marine Sci & Technol Ctr, Lab Marine Geol, Qingdao 266237, Peoples R China 3.Laoshan Lab, Deep Sea Multidisciplinary Res Ctr, Qingdao 266237, Peoples R China 4.Univ Chinese Acad Sci, Beijing 100049, Peoples R China 5.Nanjing Univ, Dept Earth & Planetary Sci, MOE Key Lab Surficial Geochem, Nanjing 210023, Peoples R China 6.Chinese Acad Sci, Nanjing Inst Geol & Palaeontol, Key Lab Palaeobiol & Petr Stratig, Nanjing 210008, Peoples R China
第一作者单位	中国科学院海洋研究所
通讯作者单位	中国科学院海洋研究所
推荐引用方式 GB/T 7714	Xue, Qiqi,Zhang, Lipeng,Chen, Shuo,et al. The source and ore-forming processes of post-collisional Qulong porphyry Cu-Mo deposit in Tibet constrained by Mo isotopes[J]. CHEMICAL GEOLOGY,2024,652:10.
APA	Xue, Qiqi,Zhang, Lipeng,Chen, Shuo,Li, Congying,Li, Tao,&Sun, Weidong.(2024).The source and ore-forming processes of post-collisional Qulong porphyry Cu-Mo deposit in Tibet constrained by Mo isotopes.CHEMICAL GEOLOGY,652,10.
MLA	Xue, Qiqi,et al."The source and ore-forming processes of post-collisional Qulong porphyry Cu-Mo deposit in Tibet constrained by Mo isotopes".CHEMICAL GEOLOGY 652(2024):10.