甘肃白银金属硫化物矿床及其矿区主要地质事件的同位素地质年代学研究

本文针对甘肃白银金属硫化物矿床长期争论的成矿时代问题，运用成因矿物学的方法，在对各采样点内锆石的标型特征、变生状态进行详细分类研究的基础上，采用锆石U－Pb同位素定年手段，测得成矿时代为464～440Ma，属加里东成矿期。同时结合矿区外围地层和岩体的同位素年代学研究，讨论了白银地区岩浆活动及主要地质事件的演化过程。

ISOTOPE GEOCHRONOGY STUDIES OF THE MAIN GEOLOGICAL EVENTS ON THE SULFIDE ORE DEPOSITS AND NEIGHBORHOOD IN BAIYIN, GANSU

This paper dealt with the metallognic epoch, that had heen argued for a long time, in the Baiyinsulfide deposit, Gansu. Based on the typomorphic feature and variable state and on the genesis mineralogy of zircons and U-Pb isotope dating, the metallogenic epoch was about 460～440Ma, and belonged to the Caledonian time. The evolution process of magmatic movements and main geologic eventswas discussed from the isotope chronogy studies combined with the surrounding strata and magmatitebodies in the Baiyin area.