滇西两个碱性岩体Rb、Sr同位素资料的再认识  

A NEW VIEWPOINT ABOUT THE RB-SR ISOTOPIC DATA OF TWO ALKALINE ROCK BODIES IN WEST YUNNAN

作　　者：刘红英[1] 张玉泉[1] 夏斌[1] 

机构地区：[1]中国科学院广州地球化学研究所,广州510640

出　　处：《云南地质》2004年第1期52-59,共8页Yunnan Geology

基　　金：中国科学院知识创新工程重要方向性项目 (KZCX2 SW 1 1 7;KZCX2 1 0 1 )

摘　　要：滇西两个碱性岩体的Rb、Sr同位素研究结果:白云山正长岩同位素年龄为85MaBP,76Sr/86Sr的初始比值为0 7097;小桥头石英正长岩87Sr/86Sr的初始比值为0 7038。另据矿物组成和地球化学特征等,表明白云山正长岩类似钠质碱性系列的岩石。The Rb-Sr isotopic composition in the whole rock samples of two alkaline plutons in west Yunnan is studied in this paper. The results show that the isotopic geological ages of the Baiyunshan syenite are from 85Ma to 83 MaBP, belonging to the late Yanshanian, and the Sr initial values of it are from 0.7097 to 0.7099. And the Sr initial value of the Xiaqiaotou quartz syenite porphyry is 0.7038. Moreover, according to the geochemical characteristics and mineral compositions the Baiyunshan syenite is similar to the sodic alkaline series rocks.

关 键 词：碱性岩体 同位素 年龄 等时线 云南 

分 类 号：P597.1[天文地球—地球化学]