锆石红外光谱在地质研究中的应用

THE APPLICATION OF ZIRCON INFRARED ABSORPTION SPECTROMETRY TO GEOLOGICAL RESEARCH

以甘肃白银厂地区的7件锆石同位素年龄样品为例,根据其红外光谱中615cm-1吸收峰的高和半高宽度的比值,将锆石样品的变生程度量化,并将其分为晶质锆石、半变生锆石和变生锆石3类。参考相关资料,利用7件锆石样品的红外光谱特征对其铀钍含量和"红外年龄"做了估测,并将估测年龄与其U Th年龄和全岩Rb Sr年龄进行了比较和分析。

This paper deals with seven zircon samples, which were collected from the Baiyinchang orefield, analyzed by the isotopic dilution technique and dated by the U-Pb Method. According to the height to the central wavelength ratio of the 615cm^(-1) absorption peak, the degrees of metamictization were measured, and the zircons were hence classified into crystalloid zircon, half-metamict zircon and metamict zircon. Having consulted some relevant data, the authors estimated the amounts of U-Th and the ages of these zircons on the basis of the zircon infrared spectrometry, and compared the infrared data with the geochronological U-Pb data of these zircons and with the Rb-Sr data of whole rocks and minerals.