摘要
朱溪钨矿床白钨矿化与矽卡岩化密切相关,白钨矿多与石榴子石、透辉石等矽卡岩矿物一起产出。该研究对朱溪典型矽卡岩矿物如石榴子石、透辉石、符山石、硅灰石、阳起石等进行显微红外光谱测量和电子探针分析,探究朱溪矽卡岩矿物的热红外光谱特征及其对成矿的指示意义,并建立朱溪地区的矽卡岩矿物热红外光谱库。结果表明,朱溪钨矿床石榴子石主要为钙铝—钙铁榴石系列,在800和920 cm^(-1)附近存在一大一小两个吸收峰,在880 cm^(-1)附近存在特征吸收谷;当石榴子石成分中钙铝榴石含量大于50%时,石榴子石特征吸收谷位于880~900 cm^(-1),当钙铝榴石含量小于50%时,石榴子石吸收谷位于865~875 cm^(-1)。随着Al 2O 3含量增加,其特征吸收谷向高波数方向移动,钙铝榴石偏向高波数,钙铁榴石偏向低波数;辉石主要为透辉石—钙铁辉石系列,在850~950 cm^(-1)波数范围内存在诊断式、呈阶梯状降低的吸收峰,且在1050 cm^(-1)处存在吸收峰,在1000 cm^(-1)存在微弱的双谷式吸收特征;随着透辉石含量的减少,MgO含量减少,透辉石吸收峰向低波数方向移动,钙铁辉石的吸收峰相对于透辉石集中在低波数范围内,与石榴子石的变化规律一致,推测与Al、Mg化学性质比Fe活泼有关。符山石拥有850~950 cm^(-1)范围内与透辉石类似形态的吸收峰,区别在于符山石在800 cm^(-1)左右还存在一吸收峰。硅灰石在875,1000和1060 cm^(-1)附近存在一大两小三个吸收峰,在980和1040 cm^(-1)附近存在两个特征吸收谷。阳起石在750和900 cm^(-1)附近存在一小一大两个吸收峰,在770,930和1020 cm^(-1)附近存在三个特征吸收谷。朱溪矿床白钨矿与石榴子石、透辉石关系最为密切,主要沿石榴子石和透辉石边界呈脉状生长,其热红外光谱可以作为寻找白钨矿的指示标志。上述研究成果,对深入分析和研究江西朱溪钨矿床的矿物学特征及成因环境,以及探索利用热红外技术指导矽卡岩矿物分带与找矿勘查的可能性等具有理论和实际意义。
The mineralization of scheelite in the Zhuxi tungsten deposits is closely related to skarnization.Scheelite is mostly produced together with skarn minerals such as garnet and diopside.In this study,for the first time,the typical skarn minerals such as garnet,diopside,vesuvianite,wollastonite and actinolite are measured by micro infrared spectroscopy and electron probe analysis to explore the thermal infrared spectral characteristics of skarn minerals in Zhuxi and their implications for mineralization,and to establish a thermal infrared spectral library of skarn minerals in Zhuxi area.The results show that the garnet in Zhuxi tungsten deposit is mainly grossular-and radite series.There are two absorption peaks(a large and a small)near 800 and 920 cm^(-1),and there is a characteristic absorption valley near 880 cm^(-1).When the grossular content in garnet is greater than 50%,the characteristic absorption valley of garnet is located at 880~900 cm^(-1).When grossular content is less than 50%,the absorption valley of garnet is located at 865~875 cm^(-1).With the increase of Al 2O 3 content in garnet,the characteristic absorption valley moves towards the high-wavenumber direction.Grossular tends to high wavenumber while andradite tends to low wavenumber;Diopside is mainly diopside-hedenbergite series.There is a diagnostic step-shaped absorption peak in the wavenumber range of 850~950 cm^(-1),anabsorption peak at 1050 cm^(-1) and a weak double-valley absorption at 1000 cm^(-1).With the decrease of diopside content,MgO content decreases the diopside absorption peak moves to the low-wavenumber direction.The absorption peak of hedenbergite is concentrated in the low-wavenumber range compared with diopside,which is consistent with the changing law of garnet.It is speculated that the reason is that Al and Mg are more active than Fe.Vesuvianite has similar absorption peaks in the range of 850~950 cm^(-1) as diopside.The difference is that vesuvianite still has anabsorption peak at 800 cm^(-1);Wollastonite has three absorption peaks(a large and two small)near 875,1000 and 1060 cm^(-1),and two characteristic absorption valleys near 980 and 1040 cm^(-1);Actinolite has two absorption peaks(a small and a large)near 750 and 900 cm^(-1),and three characteristic absorption valleys near 770,930 and 1020 cm^(-1).The scheelite mineralization in the Zhuxi deposit is most closely related to garnet and diopside,and it mainly grows in veins along the boundary of garnet and diopside.Their thermal infrared spectra can be used as an indicator for searching for scheelite.The above results have theoretical and practical significance for in-depth analysis and research on the mineralogy characteristics and genetic environment of the Zhuxi tungsten deposit in Jiangxi,as well as for exploring the possibility of using thermal infrared technology to guide skarn mineral zoning and ore prospecting.
作者
傅明海
代晶晶
王先广
胡正华
彭勃
万新
张忠雪
赵龙贤
FU Ming-hai;DAI Jing-jing;WANG Xian-guang;HU Zheng-hua;PENG Bo;WAN Xin;ZHANG Zhong-xue;ZHAO Long-xian(Ministry of Natural Resources,Key Laboratory of Metallogeny and Mineral Assessment,Institute of Mineral Resources,Chinese Academy of Geological Sciences,Beijing 100037,China;Academy of Geological Science,China University of Geosciences(Beijing),Beijing 100083,China;Jiangxi Provincical Mineral Resources Guarantee Senvice Center,Nanchang 330025,China;Jiangxi Provincial Institute Land and Space Survey and Planning,Nanchang 330025,China)
出处
《光谱学与光谱分析》
SCIE
EI
CAS
CSCD
北大核心
2023年第1期70-77,共8页
Spectroscopy and Spectral Analysis
基金
国家自然科学基金面上项目(42172332)
中央级公益性科研院所基本科研业务费专项基金项目(KK2102,KK2017)
江西省科学技术厅国家科技奖后备项目培育计划(2020年度)(20203AEI91004)资助。
关键词
热红外光谱
矿物学
矽卡岩
朱溪
Thermal infrared spectroscopy
Mineralogy
Skarn
Zhuxi
