云南省兰坪县石登—兔峨地区火山岩岩石学特征  

Petrological characteristic of volcanic rocks in the Shiden-Tu’e area,Lanping County,Yunnan

作　　者：李玫[1] 

机构地区：[1]忻州师范学院地理系,山西忻州034000

出　　处：《中国地质》2004年第1期64-69,共6页Geology in China

摘　　要：石登—兔峨地区上三叠统小定西组火山岩属云南西部澜沧江沿岸三叠系火山岩带的一部分,本文从岩相学、岩石化学和地球化学等多方面对该火山岩特征进行了系统、全面分析,并从理论角度对其形成的大地构造环境进行了判别。结果表明:该火山岩以安山岩为主,玄武岩为次,属钙碱性系列,形成于岛弧大地构造环境。Volcanic rocks in the Upper Triassic Xiaodingxi Formation in the Shiden-Tue area belong to the Tri - assic volcanic belt along the banks of the Lancang River in western Yunnan.The author has made a systematical and comprehensive study of the petrographic,petrochemical and geochemical characteristics of the volcanic rocks and determines the tectonic environment of these rocks from a theoretical angle.The study shows that these vol - canic rocks are composed dominantly of andesite with subordinate basalt,belonging to the calc-alkaline series,and formed in the island-arc tectonic environment.

关 键 词：火山岩 岩石学 岛弧构造环境 云南 

分 类 号：P588.14[天文地球—岩石学]