甘肃白银厂矿田锆石红外光谱特征和地质年龄估测

应用矿物红外光谱学的方法系统研究了白银厂地区7件锆石同位素年龄样品的红外光谱。测定结果表明，3件样品的吸收峰强而窄，整体线形与标准的晶质锆石谱线相符合；其余4件样品的吸收相对较弱，峰形圆钝；谱线均有不同程度向变生锆石特征谱线的演化，以变生程度最高的LGG-6为尤。根据615cm^-1吸收峰的H／M值可将所研究样品分为晶质锆石、半变生锆石和变生锆石三类，并利用锆石红外光谱特征估测了铀钍含量和地质年龄。同时还评估了相应样品的U-Pb同位素年龄的可靠性。

Zircon Infrared Absorption Spectrometry Features in the Baiyinchang Orefield, Gansu

This paper deals with the infrared absorption spectrometry features of the zircons dated by U-Pb method in different rocks of the Baiyinchang ore-field by the theories of mineral infrared spectrum. In the zircon infrared absorption spectrometry, we can find that the peak profiles of three zircon samples including HYS-1,XTS-2,HSS-7 are similar to that of standard crystalloid zircon. The peak profiles about the other samples are blunter than the former four samples and approaches gradually to that of metamict zircon. According to the ratio of height to the central wavelength involved 615cm~(-1) absorption band, the zircons may be divided into crystalloid zircon,half-metamict zircon and metamict zircon. The content of U-Th and geologic ages of these zircons are also estimated by the zircon infrared spectrometry features. Integrated all these studies, we further assessed the reliability of the U-Pb ages.