摘要
在"滇黔桂"、"川甘陕"两个金三角密集区内的某些卡林型金矿床中,自然砷矿物的存在并非个别现象。自然砷呈致密块状、致密凝胶体状(肾状)、脉状或微细脉状产出。自然砷呈他形粒状,颗粒大小变化较大,一般为0.05~0.50mm,最大可达2mm。反光显微镜下为白色,显微硬度为114.21~150.60kg/mm2,相当于摩氏硬度3.27~3.59。矿物主要化学成分As的质量分数为92.74%~99.74%,并含有S0.18%~5.25%,Sb0.04%~3.65%。矿物为三方晶系,晶胞参数值a=0.3759nm,c=1.0527nm。利用矿床中含砷矿物的共生组合特点及热力学资料,探讨了卡林型金矿床形成的温度、成矿流体的f(O2)、f(S2)变化范围及金以金砷络合物形式迁移的可能性。
Native arsenic is known as a rare mineral phase,but it is found in the Carlin-type gold deposits of the Yunnan-Guizhou-Guangxi and Sichuan-Gansu-Shanxi areas.Native arsenic closely associated with arsenopyrite,pyrite,stibnite,and realgar was discovered in Carlin-type gold deposits at Yata,Dongbeizhai and Jinya of the Triassic age in China.Samples were collected from Au-As or Au-As-Sb ores;native arsenic occurs in these ores in the form of compact massive,reniform shapes and as veins and veinlets.It is norma...
出处
《地学前缘》
EI
CAS
CSCD
北大核心
2007年第5期158-166,共9页
Earth Science Frontiers
基金
国家自然科学基金资助项目(40573032
4077036)
高等学校学科创新引智计划项目(B07011)
中国地质大学地质过程与矿产资源国家重点实验室项目(GPMR0527)
关键词
自然砷
矿物学特征
成矿物理化学条件
卡林型金矿床
native arsenic
mineralogical characteristic
metallogenic physicochemical condition
Carlin-type gold deposits