地质与勘探2017，Vol.53Issue(2)：207-216,10.
西藏拿若隐爆角砾岩中岩浆岩成因:来自锆石Hf同位素证据
Genesis of Magmatic Rocks of Cryptoexplosive Breccia in the Naruo Deposit of Tibet: Evidence from Zircon Hf Isotope
摘要
Abstract
The Naruo copper (gold) deposit in Tibet is one of the most important deposits in the Duolong ore-concentration area.There is a cryptoexplosive breccia associated with magmatism at the edge of the orebody.Two types of magmatic rocks are present in the cryptoexplosive breccia:one is early granite diorite porphyry,and the other is cements formed by magmatic hydrothermal causing cryptoexplosive.This work studied the zircon Hf isotopic characteristics of the two types of magmatic rocks.The results show that zircon 176Hf/177 Hf values of granite diorite porphyry are 0.282789 ～ 0.282905,176 Lu/177 Hf values of 0.000406 ～ 0.001042,εHf(t) values of 3.17 ～ 7.24 and two-stage model age (tDM 2) of 713 ～ 978Ma.Zircon 176 Hf/177 Hf values of cements are 0.282777 ～ 0.282858,176 Lu/177 Hf values of 0.000441 ～ 0.001572,εHf(t) values of 2.69 ～ 5.54,two-stage model ages (tDM 2)of 823 ～ 1005M.εHf(t) values of two magmas both are small positive values and young the two-stage model ages.Zircon Hf isotope characteristics in the cryptoexplosive breccia show that two-period magmas are characterized by crust-mantle mixing.The formation of the Naruo deposit was controlled by the Tethyan oceanic subduction.关键词
锆石Hf同位素/隐爆角砾岩/岩浆岩/拿若/多龙矿集区/西藏Key words
zircon Hf isotope/cryptoexplosive breccia/magmatic rock/Naruo/Duolong ore-concentration area/Tibet分类
天文与地球科学引用本文复制引用
高轲,唐菊兴,宋扬,刘治博,方向,杨欢欢,王勤,林彬,王艺云..西藏拿若隐爆角砾岩中岩浆岩成因:来自锆石Hf同位素证据[J].地质与勘探,2017,53(2):207-216,10.基金项目
国家自然科学青年基金(41402178)、中国地质科学院基本科研业务费(YYWF201608)、国土资源部公益性行业科研专项项目(201511017 （41402178）
201511022-02)、青藏专项地质调查项目(12120114050401)、中国地质调查局项目(DD20160026)和中铝资源西藏金龙矿业股份有限公司项目(XZJL-2013-JS03)联合资助. （12120114050401）
