祁漫塔格地区黑柱石的发现及其地质意义——以牛苦头铅锌矿为例  

Finding and significance of ilvaite in the Qimantag area-with the example of Niukutou lead and zinc deposit

作　　者：李加多 王新雨 祝新友[2] 吴锦荣 蔡亚伟 李岩 郭天军 蒋斌斌[2] LI Jia-duo;WANG Xin-yu;ZHU Xin-you;WU Jin-rong;CAI Ya-wei;LI Yan;GUO Tian-jun;JIANG Bin-bin(The Qinghai Hongxin Mining Co.,Ltd,Geermu 816099;Beijing Institute of Geology for Mineral Resources,Beijing 100012)

机构地区：[1]青海鸿鑫矿业有限公司 [2]北京矿产地质研究院,北京100012

出　　处：《矿产勘查》2019年第7期1550-1558,共9页Mineral Exploration

摘　　要：黑柱石属于矽卡岩矿物中比较少见的一种含钙铁硅酸盐矿物,对于矽卡岩成矿作用具有较好的指示意义。祁漫塔格地区是我国重要的多金属成矿带,然而该地区鲜有矽卡岩中黑柱石的报道研究。本次研究对祁漫塔格地区牛苦头铅锌多金属矿床的退变质矽卡岩阶段黑柱石的产出地质背景、矿物共生组合、化学成分等进行了研究,将牛苦头矿区黑柱石分为两类:一种与阳起石、方铅矿、闪锌矿共生,另一种与磁黄铁矿共生。根据电子探针分析结果计算,牛苦头矿区两类黑柱石的化学简式分别为Ca0.96(Fe1.64-1.68Mn0.21-0.23Mg0.02)(1.89-1.91)^2+(Fe0.93-0.96Al0.04-0.07)(0.97-1.00)^3+[Si2.05-2.07O7]O(OH),Ca0.95-0.97(Fe1.42-1.59Mn0.33-0.45Mg0.01-0.02)(1.84-1.90)^2+(Fe0.93-0.98Al0.02-0.06)(0.95-1.00)^3+[Si2.05-2.06O7]O(OH)。牛苦头矿区黑柱石的形成于中酸性火山岩活动有关,通过与国内外其他矿区黑柱石的化学成分进行对比。笔者认为,牛苦头矿区黑柱石为锰质黑柱石,一般存在于矽卡岩型铅锌多金属矿中,而与矽卡岩型金、铁矿床黑柱石类型有所不同,后者多属于普通黑柱石。综合研究表明,锰质黑柱石的出现更有利于矽卡岩铅锌矿床的形成,因此,锰质黑柱石可以作为矽卡岩铅锌矿床找矿的标志,在矽卡岩找矿工作中应引起足够重视。Ilvaite,an uncommon type of skarn typomorphic mineral,was first found in Niukutou lead and zinc deposit deposit,Qimantag Area.The Qimantag metallogenetic belt is an important Skarn metallogenic belt in china,however,few research ilvaite about has been reported.In this study geological occurrence,mineral association,chemical composition and optical property of ilvaite in Niukutou deposit were discussed,and deviding the ilvaite into two categories:Actinolite-ilvaite skarn with lead and zinc,the ilvaite skarn pyrrhotite.The mineral chemical composition by EPMA showed that the molecular formula of the Niukutou ilvaite is Ca0.96(Fe1.64-1.68Mn0.21-0.23Mg0.02)(1.89-1.91)^2+(Fe0.93-0.96Al0.04-0.07)(0.97-1.00)^3+[Si2.05-2.07O7]O(OH),Ca0.95-0.97(Fe1.42-1.59Mn0.33-0.45Mg0.01-0.02)(1.84-1.90)^2+(Fe0.93-0.98Al0.02-0.06)(0.95-1.00)^3+[Si2.05-2.06O7]O(OH)respectively.And the formation of Niukutou deposit is closely realted to the intermediate-acid magmatic rocks.Combined with the skarn deposit with ilvaite at home and abroad,we believe that the Niukutou ilvaite is Mn-rich ilvaite,which is available in Skarn Zinc Deposit,and is different from the ilvaite of Skarn Au-Fe Deposit.Thus,we prefer that the Mn-rich ilvaite may be favorable for the formation of Skarn Zinc Deposit.It is also suggested that Mn-rich ilvaite is a kind of important mineral in Skarn Zinc Deposit and should be paid more attention.

关 键 词：锰质黑柱石 矽卡岩型铅锌矿 祁漫塔格地区 

分 类 号：P611.1[天文地球—矿床学]