摘要
初步分析了纳多弄地区辉绿岩的岩石地球化学特征。研究区辉绿岩为钙碱性系列,总体低TiO2。部分样品Sr元素相对亏损,中等负Eu异常,大离子亲石元素(LILE)相对富集,轻稀土(LREE)相对富集,而其余样品无Sr,Eu异常,无大离子亲石元素(LILE)及轻稀土(LREE)富集。据岩石地球化学对比结果,认为其兼具MORB与OIB特征。结合班公湖-怒江洋盆构造演化历史,纳多弄辉绿岩应是班公湖-怒江洋盆向南的俯冲作用在冈瓦纳北部陆缘形成的弧后扩张盆地环境的产物。
Major and trace elements of diabases from the Naduonong area in Luolong (Eastern Tibet) are reported in this study.The diabases all belong to calc-alkaline series and have moderate TiO2 contents.Some of the samples have Sr and mediocre Eu depletion,and have low-grade LILE and LREE enrichment.Other samples have no obvious Sr and Eu depletion,no LILE and LREE enrichment.It is similar to both E-MORB and typical arc basalts.It is proposed that the Naduonong diabases were formed in an arc-backarc environment which was formed by southward subduction of the Ban-gonghu-Nujiang oceanic crus.
出处
《新疆地质》
CAS
CSCD
北大核心
2014年第1期102-107,共6页
Xinjiang Geology
基金
国土资源部中央地质勘查基金<西藏洛隆县纳多弄铅锌多金属矿普查>项目资助
