哀牢山北段金矿带铅同位素特征研究

A STUDY ON THE PB ISOTOPIC FEATURES OF AU DEPOSIT ZONE IN THE N SECTION OF AILAO MTS

以哀牢山北段金矿带中最大金矿田──老王寨金矿田为例，从铅同位素组成，源区特征，单阶段模式年龄，铅源初始年龄及与墨江金厂矿石铅同位素对比等五个方面，结合图表解析，论述了金矿带的铅同位索特征，指出本区铅同位素组成是基本稳定的，且主要属造山带铅。从铅同位素一个侧面证实哀牢山北段金矿带矿化从燕山期到喜马拉雅期，且以喜马拉雅期矿化为主，参加矿化物质显示多期多阶段性的特点。

Laowangzhai Au ore-field is the largest ore-field of the Au deposit zone in the north sec-tion of Ailao Mountains. Taking it as an example, the Pb isotopic features of this Au epositzone are described in this paper based upon Pb isotopic composition, features of origin area,single-stage model age, initial age of Pb origin, correlation with the Pb isotope of Jinchang ore, Mojiang and in connection with diagram analysis. The study results indicate that the Pb isotopic composition in this area is basically stable and mainly belongs to the orogenic zone Pb. The Pb isotope in one aspect confirms the metallogenesis of Au deposit zone in the north section of Ailao Mountains took place from Yanshanian to Himalayan, mainly in Himalayan,and the metallogenetic material shows the features of multiperiod and multistage.