Geological characteristics,metallogenic background,and genesis of the Tongyu VHMS copper deposit in

来源 :Science China(Earth Sciences) | 被引量 : 0次 | 上传用户:dayongxue
下载到本地 , 更方便阅读
声明 : 本文档内容版权归属内容提供方 , 如果您对本文有版权争议 , 可与客服联系进行内容授权或下架
论文部分内容阅读
The Tongyu volcanic-hosted massive sulfide(VHMS) copper deposit is located in the west part of the North Qinling(NQL),Shaanxi Province.Here we report geological features and trace elemental characteristics of ores,mineralized rocks,and volcanic host rocks of this deposit.We also conducted in situ zircon U-Pb and Lu-Hf LA-ICP-MS dating and lithogeochemical study of the Meigou granodiorite,which is intruded in the south of the Tongyu mining district.It is inferred that the volcanic host rocks of the Tongyu Cu deposit belong to calc-alkaline island arc volcanic rocks,and the volcanic host rocks and the ore-forming materials share common material sources.During subduction of the Paleo-Qinling oceanic slab at around 472 Ma,high oxygen-fugacity aqueous fluid released by dehydration reaction of the subducting slab rose into the mantle wedge,leached Cu and other metal elements,and triggered partial melting of the mantle wedge.Associated with the ore-forming materials,the arc calc-alkaline magmas erupted and formed the Tongyu VHMS deposit.The weighted average zircon U-Pb age of the Meigou granodiorite is 439.3±3 Ma,suggesting its genesis is associated with the subduction event of the Paleo-Qinling oceanic plate around 440 Ma.In terms of the granitoid’s geochemical characteristics,the Mg#,Ni,and Cr contents are high.REE show strongly fractionated patterns with unobvious Eu anomalies.Sr contents are high while Y contents are low,resulting in high Sr/Y ratios.Two-stage zircon Hf model ages mostly range between 908 and 723 Ma,with εHf(t)>0.Therefore,we classify Meigou granodiorite as island arc granite with adakitic geochemical features.It was generated by interaction between mantle wedge and melt produced by partial melting of the subducted basaltic slab of the Paleo-Qinling Ocean.The Tongyu VHMS deposit was formed in the island arc tectonic setting during Ordovician-Silurian between 439.3±3 Ma and 472±11 Ma.The volcanic exhalation-sedimentation,which was contemporaneous with the submarine volcanics,produced the primary mineralization of the Tongyu Cu deposit.Afterward,the ore bodies and host rocks were reworked and overprinted intensively by structures corresponding with the overall collisional orogenic process of the Qinling Orogenic Belt during the Indosinian period.In contrast to classic VHMS deposits such as the Kuroko deposit in Japan,the Tongyu Cu deposit possesses the dual characteristics of island arc volcanic exhalation and sedimentation as well as structural reworking and overprinting.Therefore,the Tongyu VHMS Cu deposit is a volcanic exhalation and sedimentation-structural reworking and overprinting type deposit. The Tongyu volcanic-hosted massive sulfide (VHMS) copper deposit is located in west part of the North Qinling (NQL), Shaanxi Province. Here we report geological features and trace elemental characteristics of ores, mineralized rocks, and volcanic host rocks of this deposit.We also conducted in situ zircon U-Pb and Lu-Hf LA-ICP-MS dating and lithogeochemical study of the Meigou granodiorite, which is intruded in the south of the Tongyu mining district. It is inferred that the volcanic host rocks of of the Tongyu Cu deposit belong to calc-alkaline island arc volcanic rocks, and the volcanic host rocks and the ore-forming materials share common material sources. Drawing subduction of the Paleo-Qinling oceanic slab at around 472 Ma, high oxygen-fugacity aqueous fluid released by dehydration reaction of the subducting slab rose into the mantle wedge, leached Cu and other metal elements, and triggered partial melting of the mantle wedge. Associated with the ore-forming materials, the arc calc-alkaline magm as erupted and formed the Tongyu VHMS deposit.The weighted average zircon U-Pb age of the Meigou granodiorite is 439.3 ± 3 Ma, suggesting its genesis is associated with the subduction event of the Paleo-Qinling oceanic plate around 440 Ma. terms the granitoid’s geochemical characteristics, the Mg #, Ni, and Cr contents are high .REE show strongly fractionated patterns with unobvious Eu anomalies. Sr contents are high while Y contents are low, resulting in high Sr / Y ratios. Two-stage zircon Hf model ages mostly between 908 and 723 Ma, with εHf (t)> 0. Therefore, we classify Meigou granodiorite as island arc granite with adakitic geochemical features. It was generated by interaction between mantle wedge and melt produced by partial melting of the subducted basaltic slab of the Paleo-Qinling Ocean. The Tongyu VHMS deposit was formed in the island arc tectonic setting during Ordovician-Silurian between 439.3 ± 3 Ma and 472 ± 11 Ma. The volcanic exhalation-sedimentation, which was contemporaneous wi th the submarine volcanics, produced the primary mineralization of the Tongyu Cu deposit. Afterward, the ore bodies and host rocks were reworked and overprinted intensively by structures corresponding with the overall collisional orogenic process of the Qinling Orogenic Belt during the Indosinian period. contrast to classic VHMS deposits such as the Kuroko deposit in Japan, the Tongyu Cu deposit possesses the dual characteristics of island arc volcanic exhalation and sedimentation as well as structural reworking and overprinting.Therefore, the Tongyu VHMS Cu deposit is a volcanic exhalation and sedimentation-structural reworking and overprinting type deposit.
其他文献
现代学徒制脱胎于传统学徒制,是企业培训与学校教育相结合的职业教育制度,在实现产教融合、校企合作、工学结合等方面具有明显的优势。中小微企业在转型升级过程中,迫切需要
在整个社会生活中,礼仪是专门用来表现对别人尊重的一种沟通工具、行为技巧和行为方式,也是人的一种境界。一般来说,礼仪分两个层面:内在的尊重叫礼,外在的表现叫仪。
国务院总理李克强在今年的政府工作报告中提出,要“培育精益求精的工匠精神”。培育工匠精神,是时代的呼唤,是各行各业的责任,特别是职业院校义不容辞的义务。最近我们到苏州
目的 探讨吡拉西坦联合七叶皂苷钠治疗脑出血的临床疗效.方法 选取2014年7月—2016年7月在盐亭县人民医院进行治疗的脑出血患者62例,依据治疗方法的不同分为对照组(31例)和治疗
在咨询的过程中,常常会遇到这样一些学生,他们因遭遇失恋而痛苦得死去活来,并认为自己是世界上最不幸的人。他们极力地想挽回失恋的局面,并努力地寻找、修正自身的缺陷,希望
《地质找矿论丛》为国家科技部和新闻出版署批准 ,由天津地质研究院主办的地学类科技期刊 ,1986年创刊 ,国内外公开发行。标准刊号 :ISSN 10 0 1—1412 ,CN 12— 1131 P。《地质找矿
据调查,80%的夫妻关系出现问题是因为性生活不和谐,若加上“不满足”的部分,这个比例则高达90%以上。“不建议大家去学习体位,瑜珈高手也不过108式,再翻来覆去总有厌倦的一天
社会大变革给我们带来的不仅仅是物质生活上的极大富足,随之而来的还有人们在精神世界悄然无声的革新。分裂、重组家庭的增多便是这些革新所带来的最直接的体现。对于再婚家
1.科研设计:科研设计及施行应遵循随机、对照、重复、均衡4个基本原则,来稿中宜就此概要说明,尤其要交代如何控制重要非研究因素的干扰和影响。应说明科研设计的设计方案和设
“你可以做任何你想做的事情。”那天晚上,他一边把女儿放到床上一边说。小女孩的眼中到处是繁星闪闪,她的心中也充满了很多很多的梦想。小女孩完全相信自己的父亲,而且梦想