投稿时间:2016-10-23
修订日期:2016-12-24
网络发布日期:2017-05-13
中文摘要:东戈壁钼矿床处于东天山觉罗塔格成矿带的中部,是该地区三叠纪钼成矿带的代表性矿床之一。东戈壁矿床赋存于石炭系干墩组一套浅变质碎屑岩中,隐伏于矿体下部的花岗斑岩为其成矿岩体。文章对东戈壁钼矿床成矿岩体进行了地质特征、岩相学、电子探针和地球化学分析,结果显示东戈壁花岗闪长斑岩的斜长石为中长石-更长石-钠长石系列,钾长石为正长石,黑云母为铁质黑云母。全岩地球化学分析显示东戈壁花岗斑岩为高硅(w(SiO2)73.36%~74.34%)、高钾(w(K2O)4.49%~5.61%)、弱过铝质(A/CNK:1.03~1.14)的特点。成因研究显示东戈壁花岗斑岩为I型花岗岩,形成于挤压环境的地壳源区,在上升过程中经历了显著分离结晶形成的高分异岩浆岩。通过对同一时空背景下的东戈壁和白山2个钼成矿岩浆岩开展的矿物学和地球化学等方面的对比研究,表明东戈壁钼矿床花岗斑岩与白山花岗斑岩分别具有地壳源区和地幔源区的特点,是不同岩浆-热事件的产物。
Abstract:Located in the central part of the Jueluotage metallogenic belt, the Donggebi Mo deposit is one the largest Middle Triassic Mo deposits in northern Xinjiang. The Donggebi Mo deposit occurs in the late Carboniferous Gandun Formation, and is genetically related to the mineralized granite porphyry beneath the orebodies. This study focused on the geology, petrography, rock-forming minerals EPMA and geochemistry of the Donggebi mineralized granite porphyry, and the results show that the feldspars and biotites in the Gonggebi mineralized granite porphyry are mainly acidic plagioclase and K-feldspar, and Fe-rich biotite. The whole-rock geochemistry shows that the mineralized granite porphyry is Si-high (w(SiO2) 73.36%~74.34%), K-high (w(K2O) 4.49%~5.61%), and weakly peraluminous (A/CNK: 1.03~1.14) I-type granite. The primary magma was formed in the deep crust source in a convergence environment, and experienced significant fractional crystallization during its emplacement. The Donggebi Mo deposit shared the same temporal and spatial background with the Baishan Mo deposit in Jueluotage area. Based on a comparison of petrogenetic characteristics between the mineralized granite porphyry in the Donggebi Mo deposit and that in the Baishan Mo deposit, the authors have found that the two mineralized granite porphyry intrusions beneath Donggebi and Baishan Mo deposits were derived from crust and mantle sources respectively, being different magma-thermal products.
文章编号:
中图分类号:P618.65
文献标志码:
基金项目:本文得到国家自然科学基金项目(编号:41302050)、"十二五"国家科技支撑计划项目(编号:2011BAB06B01)、博士后科学基金第56批面上项目(编号:2014M562488)、中国地质调查局地质调查项目(编号:DD20160039)、中央高校基本科研业务费专项(编号:JZ2016HGTB0730)、中国科学院"西部之光"人才培养引进计划项目和新世纪优秀人才支持计划项目(编号:NCET-100324)联合资助
引用文本:
叶龙翔,张达玉,周涛发,袁峰,张永,邓宇峰,徐利强,路魏魏.2017.新疆觉罗塔格地区东戈壁钼矿床花岗斑岩的成因研究[J].矿床地质,36(2):429~448YE LongXiang,ZHANG DaYu,ZHOU TaoFa,YUAN Feng,ZHANG Yong,DENG YuFeng,XU LiQiang,LU WeiWei.2017.Petrogenesis of mineralized granite porphyry in Dongebi Mo deposit, Jueluotage area, Xinjiang[J].Mineral Deposits36(2):429~448
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