投稿时间：2010-12-17
修订日期：2012-06-22
中文摘要:文章在详细的野外地质调查、岩石学、岩石化学和锆石U-Pb定年结果基础上,对浙江安吉矿区细粒花岗岩的岩浆起源、侵位时代与成矿的关系及找矿指示意义等进行了较为深入的探讨。细粒花岗岩侵位时代晚于矿区的黑云母二长花岗岩、正长花岗岩和花岗闪长岩,侵位时代约在134 Ma左右,为中国东部晚侏罗世—早白垩世岩石圈活化及大规模成岩成矿作用的产物。岩石化学研究结果表明,细粒花岗岩属高钾钙碱性-钾玄岩、过铝质岩石系列,轻稀土元素相对富集,重稀土元素相对亏损,富集大离子亲石元素Rb、Th、U、K、轻稀土元素和Pb,明显亏损高场强元素Nb、Ta、Ti和P,显示较高的分异程度。据根锆饱和温度,计算其母岩浆结晶温度约在834.6~870.6℃。结合矿区已知的矿化和蚀变与细粒花岗岩的空间关系、细粒花岗岩岩石化学特征以及细粒花岗岩与矿石铅同位素研究结果,笔者认为,安吉铅锌多金属矿区铅锌钼矿化与细粒花岗岩具有密切的成因联系,细粒花岗岩与寒武系灰岩接触部位控制了矽卡岩型铅锌矿化的产出,这一成果对该区的进一步找矿勘查具有重要的指导意义。
Abstract:Based on ore deposit geology, petrogeochemistry and chronology of fine crystalline granite, this paper discusses the magma sources, intrusive age of fine crystalline granite and their genetic link with Pb-Zn mineralization in this area. The results indicate that the fine crystalline granite intruded into biotite monzonitic granite at about 134 Ma, which was consistant with lithosphere activation and large-scale diagenesis-metallogenesis event in East China. Petrochemical studies show that the fine crystalline granites belong to high-K calc-alkalic to shoshonitic series with peraluminous characteristics. Main and trace element compositions show a transitional character from type I to type S granite. The estimated magma temperatures are about 834.6~870.6℃ according to Zr saturation thermometer. The distribution of known mineralization in the ore district, the petrochemistry of fine crystalline granite and Pb isotopic analyses indicate that the Pb-Zn (Mo) mineralization has genetic link with this granite intrusion. The contact zone between fine crystalline granite and Cambrian limestone controls the skarn-type Pb-Zn mineralization. The results have important implications for exploration in this area.
keywords:geochenmistry Pb-Zn polymetallic deposit fine crystalline granite zircon U-Pb dating geological significance Anji of Zhejiang Province
文章编号：
中图分类号：P618.42;P618.43
文献标志码：
基金项目:本文是国土资源部公益性行业基金项目(编号:201011011)和十二五国家科技计划项目(编号: 2011BAB04B00)联合资助的成果
引用文本：
谢玉玲,唐燕文,李应栩,邱立明,刘保顺,李媛,张欣欣,韩宇达,姜妍岑.2012.浙江安吉铅锌多金属矿区细粒花岗岩的岩石化学、年代学及成矿意义探讨[J].矿床地质,31(4):891~902XIE YuLing,TANG YanWen,LI YingXu,QIU LiMing,LIU BaoShun,LI Yuan,ZHANG XinXin,HAN YuDa,JIANG YanCen.2012.Petrochemistry, chronology and ore-forming geological significance of fine crystalline granite in Anji polymetallic deposit of Zhejiang Province[J].Mineral Deposits31(4):891~902
图/表
