Knowledge Network Node
Mineral Deposits. 2021, (05) Core

Metallogenesis of Himalaya gneiss dome:An example from Cuonadong gneiss dome in Zhaxikang ore concentration areaChinese Full TextEnglish Full Text (MT)

LIANG Wei;LI GuangMing;BASANG Yuandan;ZHANG LinKui;FU JianGang;HUANG Yong;ZHANG Zhi;WANG YiYun;CAO HuaWen;Chengdu Institute of Geology and Mineral Resources,China Geological Survey;Center of Land Mining Rights Trading and Resource Reserve Evaluation,Tibet Autonomous Region;

Abstract: The Tethys Himalaya Gneiss Dome（THGD） is parallel to the orogenic belt,which is closely related to the gold,antimony,lead-zinc and tin-tungsten-beryllium polymetallic deposits in the Himalaya orogenic belt.The Zhaxikang lead-zinc polymetallic Ore concentration Area（ZOA） in southern Tibet is the most famous ore-concentrating area in the Himalayan orogenic belt,more than dozens of gold-anitimony,lead-zinc and beryllium-tungsten-tin deposits with different tonnages were formed within it.The ore deposits in the ZOA are concentrated around the Cuonadong gneiss dome in the central part of this area,and occurred in the sequence of berylliumtungsten-tin rare metal ores → lead-zinc polymetallic ores → gold and/or antimony ores from the core of the dome to the rim,which are consistent with the 1:50 000 scale regional stream sediment geochemical anomaly represented by a zonation of high temperature elements（W,Sn,Bi,Rb） in the core of the dome→ medium temperature elements（Pb,Zn,Ag,Sb） in the outer contact zone of granite → medium and low temperature elements（Au,Sb,Ag,Hg,As） in the peripheral country rocks.The Cuonadong Dome was mainly formed in Miocene,during which a number of leucogranites（23～14 Ma） were emplaced,and the "metallogenic explosion"（21～12 Ma） of ZOA took place during this time.The H-O isotopes indicate that the ore-forming fluids within ZOA have contribution of magmatic hydrothermal fluid in different degrees.The Pb isotopes indicate that Be-W-Sn is derived from leucogranite,and Pb-Zn has multi-sources,which could come from leucogranite and ancient metamorphic basement rocks,while the Au（Sb） is mainly derived from mafic dikes and basalts related to the mantle or lower crust.Based on analysis on the spatial and temporal distribution,fluid and material source of typical deposits,it is considered that the formation of polymetallic deposits in ZOA is a tectonic-magmatic-metallogenic event triggered by the doming in the Himalayan belt,which constitutes an doming controlled Au-Sb-Pb-Zn-W-Be polymetallic metallogenic system.The Himalayan orogenic belt has been in an extensional period since the Miocene,and multiple periods of leucogranites anatexis have been developed in this area that formed gneisses dome centered at Cuonadong.The anatexis intrusions are highly evolved leucogranites,with exsolution of Be-W-Sn-Rb bearing magmatic fluid in late magmatic evolution.With the high geothermal gradient caused by the magma emplacement,the magmatic fluid diffused outward,forming pegmatite-type Be-Rb rare-metal deposits at the top of the magma,and forming skarn-type Be rare metal deposits when metasomated with marble in the contact zone of the granite,and also forming cassiterite-sulfide vein type tin polymetallic ores in the Cuonadong detachment faults and the near north-south striking extensional fault systems.In the process of flowing outward,the ore-forming elements in various geological bodies are extracted,and mixed with varying degrees of meteoric water and geothermal water,forming Pb-Zn deposits in the peripheral extensional fractures,and Au-Sb ores at a lower temperature.
Keywords：

geology; metallogenesis in dome; Zhaxikang ore-concentration area; tectonic-magmatic-hydrothermal system; Himalaya orogenic belt;

  • DOI：

    10.16111/j.0258-7106.2021.05.003

  • Series：

    (A) Mathematics/ Physics/ Mechanics/ Astronomy; (B) Chemistry/ Metallurgy/ Environment/ Mine Industry

  • Subject：

    Mining Engineering; Geology

  • Classification Code：

    P618.2

Download the mobile appuse the app to scan this coderead the article.

Tips: Please download CAJViewer to view CAJ format full text.

Download: 380 Page: 932-948 Pagecount: 17 Size: 5841K

Related Literature
  • Similar Article
  • Reader Recommendation
  • Associated Author