| 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 |
| |
| 引用本文： | 高,轲.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. |
| |
| 作者姓名： | 高 轲 |
| |
| 作者单位： | 成都理工大学 地球科学学院，四川成都；中国地质科学院矿产资源研究所，北京 |
| |
| 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；201511022-02)，青藏专项地质调查项目（12120114050401），中国地质调查局项目（DD20160026），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。 |
| |
| 摘 要： | 西藏拿若铜(金)矿床是多龙矿集区重要矿床之一,矿体边部存在一岩浆作用的隐爆角砾岩筒。隐爆角砾岩中存在两种岩浆岩:一种是早期花岗闪长斑岩;一种是引起隐爆作用的岩浆热液形成的胶结物。此次工作以两种岩浆岩为对象,研究其锆石的Hf同位素特征。花岗闪长斑岩的锆石~(176)Hf/~(177)Hf值介于0.282789~0.282905之间,176Lu/177Hf值介于0.000406~0.001042之间,ε_(Hf)~(t)值介于3.17~7.24之间,二阶模式年龄(tDM2)为713~978Ma。胶结物锆石的~(176)Hf/~(177)Hf介于0.282777~0.282858之间,~(176)Lu/~(177)Hf值介于0.000441~0.001572之间,ε_(Hf)~(t)值为2.69~5.54,二阶模式年龄(tDM2)为823~1005M。两期岩体的ε_(Hf)~(t)值都是较小的正值,都具有年轻二阶模式年龄。拿若隐爆角砾岩中锆石Hf同位素特征显示,两期岩浆均具有壳幔混源的特征。拿若矿床的形成受控于特提斯洋壳俯冲作用。
|
| 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 |
| 收稿时间： | 2016/11/8 0:00:00 |
| 修稿时间： | 2017/3/2 0:00:00 |
Genesis of magmatic rocks of cryptoexplosive breccia in the Naruo deposit of Tibet: Evidence from zircon Hf isotope |
| |
| Gao Ke.Genesis of magmatic rocks of cryptoexplosive breccia in the Naruo deposit of Tibet: Evidence from zircon Hf isotope[J].Geology and Prospecting,2017,53(2):207-216. |
| |
| Authors: | Gao Ke |
| |
| 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. |
| |
| Keywords: | zircon Hf isotope cryptoexplosive breccia magmatic rock Naruo Duolong ore-concentration area Tibet |
| 本文献已被 CNKI 万方数据 等数据库收录！ |
| 点击此处可从《地质与勘探》浏览原始摘要信息 |
| 点击此处可从《地质与勘探》下载免费的PDF全文 |
