新疆东准噶尔锡、金矿区石英薄片的红外光谱特征及其在成矿条件分析中的应用

THE INFRARED SPECTRA OF THE QUARTZ THIN-SECTION AND ITS APPLICATION TO THE STUDY OF MINERALIZATION IN GOLD AND TIN DEPOSITS, EASTERN JUNGGAR, XINGJIANG

石英薄片的红外吸收光谱可以用来研究石英中的气液包裹体井分析其成因。新疆东准噶尔锡矿区石英薄片的红外光谱特征主要反映了石英脉的形成条件和环境,但不能直接区分含矿与不含矿石英脉,金矿区石英薄片的红外光谱特征则很大程度上与石英中气液包裹体的数量有关,这在一定程度上反映了热液活动的强度和次数,从而也就反映了石英脉的含金性。

The infrared spectra of the quartz thin-section may be used to study fluid inclusions in quartz and analyse their genesis. In gold deposits, we can use the infrared spectra to distinguish auriferous quartz vein from non-auriferous one;thus gold deposits can be assessed rather efficiently and economically. In tin deposits, they provide us a new clue for solving the physical conditions of ore-forming process.On the infrared spectra of quartz thin-section of six gold deposits in eastern Junggar, the relative-absorbance of water in the Nann inshui, Jinshangou,Qingshui and Hongshan gold deposits water is higher than one, while that in the Jinshan and Xiaojingou gold deposits is lower than one, so tile gold content of quartz in the former is higher than that of the latter.The infrared spectra of quartz thin-section of three tin deposits in eastern Junggar show that the infrared spectra can not be used to distinguish ore-bearing quartz vein from barren quartz vein;the relative-absorbance of water appears to have a definite relation with the homogenization temperature of fluid inclusions in quartz: the higher the homogenization temperature, the lower the relative-absorbance of water. In the Sabei tin deposit, on the infrared spectra of quartz thinsection, the absorption band of water is very weak. It indicated that the Sabei tindeposit was mainly formed in a plutouic and water-deficient environment. It is a hypothermal deposit with more or less pneumatolytic nature, In the Beilekuduke tin deposit, the relative-absorbance of water is high in some cases and low in others, indicating that the ore-forming fluids were varied, including both hypothernmal fluids with a bit pneumatolytic nature and mesothermal and epithermal fluids. In the Kamosite tin deposit, the relative-absorbance of water is relatively high, which shows that the metallogenic environment in the Kamosite deposit is hypabyssal and rich in water as compared with the Sabei and Beilekuduke deposits.