郑明华矿(Zhengminghuaite):黔西南卡林型金矿床中新矿物的发现及其成矿学意义  

Zhengminghuaite:A new mineral from Carlin-type gold deposits in southwest⁃ern Guizhou and its metallogenic significance

作　　者：顾雪祥[1,2] 章永梅[1,2] 范光[3] 李婷[3] 董树义[4] 彭义伟 杨成富[5] 李羚 GU XueXiang;ZHANG YongMei;FAN Guang;LI Ting;DONG ShuYi;PENG YiWei;YANG ChengFu;LI Ling(School of Earth Sciences and Resources,China University of Geosciences,Beijing 100083,China;State Key Laboratory of Geological Processes and Mineral Resources,China University of Geosciences,Beijing 100083,China;Beijing Research Institute of Uranium Geology,Beijing 100029,China;Chengdu University of Technology,Chengdu 610059,Sichuan,China;No.105 Geological Team,Guizhou Bureau of Geology and Mineral Exploration and Development,Guiyang 550001,Guizhou,China)

机构地区：[1]中国地质大学(北京)地球科学与资源学院,北京100083 [2]中国地质大学(北京)地质过程与矿产资源国家重点实验室,北京100083 [3]核工业北京地质研究院,北京100029 [4]成都理工大学,四川成都610059 [5]贵州省地质矿产勘查开发局105地质大队,贵州贵阳550001

出　　处：《矿床地质》2024年第4期735-748,共14页Mineral Deposits

基　　金：国家自然科学基金重点项目《沉积盆地中金属成矿与油气成藏关系研究——以右江、兰坪盆地为例》(编号:40930423);《新疆西天山北缘晚古生代斑岩-矽卡岩型铜钼铁多金属成矿与岩浆-热液作用过程》(编号:42130804);新疆维吾尔自治区“天池英才”计划联合资助。

摘　　要：郑明华矿是最近在黔西南紫木凼卡林型金矿床中发现的一种硫盐类新矿物。文章在概述郑明华矿产出状态、物理性质、光学特征、化学组成和晶体结构基础上,侧重介绍该新矿物形成的地质背景、显微组构特征及与同型系列其他矿物的关系,并结合矿物共生组合特征,探讨其形成的物理化学条件。郑明华矿产于受断层破碎带控制的角砾状金矿石中,与其共生或伴生的矿物为成矿晚阶段石英、雄黄和方解石,以及少量至微量As-Sb-Hg-Tl的硫化物和硫盐。郑明华矿为不透明矿物,金属光泽,性脆易碎,无解理,莫氏硬度约为4;反射色为浅灰色,双反射和反射多色性不显至微弱,非均质性微弱,反射率为23%~29%(546 nm);理想化学式为Cu_(6)Fe_(3)As_(4)S_(12),三方晶系,空间群R3,晶胞参数:a=13.5373(17)Å,c=9.2354(13)Å,V=1465.7(4)Å^(3)(Z=3),属硫砷锌铜矿同型系列的新矿物。郑明华矿形成于成矿主阶段含金富砷黄铁矿、毒砂等Fe硫化物沉淀后的成矿晚阶段,但主要形成于雄黄等As硫化物大量沉淀前,在此期间成矿流体的硫逸度(f(S_(2)))升高了1~2个对数单位,温度降低了60~100℃。郑明华矿的发现及与其他热液矿物的共生组合关系,为揭示卡林型金矿床的成矿过程和成矿物理化学条件提供了重要信息。Zhengminghuaite is a new sulfosalt mineral recently found in the Zimudang Carlin-type gold deposit in southwestern Guizhou.Based on an overview of occurrence,physical and optical properties,chemical composition and crystal structure of the new mineral,the major purpose of this contribution is to document the geological background,microtextures,and relations to other mineral species of isotypic series,and combined with paragenetic sequence,to discuss the formation condition of the new mineral.Zhengminghuaite occurs in fault-controlled brecciated gold ores and is paragenetically associated with the late ore-stage quartz,realgar,calcite,and minor to trace amounts of As-Sb-Hg-Tl sulfides and sulfosalts.Zhengminghuaite is opaque and brittle with a metallic luster.It shows no cleavage and has a Mohs hardness of~4.In reflected light,zhengminghuaite is whitish gray,with no to weak bireflectance and reflection pleochroism,very weak anisotropy,and a reflectance of 23%~29%(546 nm).Zhengminghuaite is trigonal,with space group R3 and unit-cell parameters of a=13.5373(17)Å,c=9.2354(13)Å,and V=1465.7(4)Å^(3)(Z=3).It belongs to a new member of the nowackiite isotypic series with an ideal formula of Cu_(6)Fe_(3)As_(4)S_(12).Paragenetic relationships indicate that zhengminghuaite precipitated after the deposition of auriferous arsenian pyrite and arsenopyrite,but was prior to the bulk deposition of realgar,during which the sulfur fugacity(f(S_(2)))of the ore fluid increased by 1~2 log units and the temperature decreased by 60~100℃.

关 键 词：郑明华矿 硫盐 新矿物 卡林型金矿床 成矿意义 黔西南 

分 类 号：P578.2[天文地球—矿物学]