镇康地区晚三叠世火山岩特征及构造意义  

THE FEATURE AND TECTONIC SIGNIFICANCE OF LATE TRIASSIC VOLCANIC ROCK IN ZHENKANG AREA

作　　者：左琼华[1] 朱婉明[1] 戚戎辉 

机构地区：[1]云南国土资源职业学院,云南昆明650217 [2]云南省地质调查院,云南昆明650217

出　　处：《云南地质》2016年第4期451-456,共6页Yunnan Geology

摘　　要：镇康地区上三叠统牛喝塘组(T3nh)火山岩大类上分为基性火山岩和中酸性火山岩,基性火山岩以橄榄安粗岩亚系列为主,中酸性火山岩以高钾钙碱亚系列为主;该火山岩从东往西火山岩层厚度由厚变薄,酸性火山岩及火山碎屑岩有逐渐递减且沉积岩夹层逐渐增多的趋势,表明火山机构位于东部。从火山岩石总体上的化学特征显示,该地区晚三叠世火山岩形成于板块内部环境,属于陆内拉张型火山岩。The Late T Niuhetang Formation （T3nh） volcanic rock in Zhenkang area can be divided into basic volcanic rock and intermediate-acid volcanic rock in large type. The former one is mainly to the woodendite sub- se- ries, whereas the latter is mainly to the high-K calc alkali sub- series. The thickness of volcanic rock decreases from E to W. The acid volcanic rock and volcanic clastic rock progressively decrease and sedimentary rock interca-lation increases progressively, showing the volcanic mechanism is in the E. According to the general chemical fea-ture of volcanic rock, the Late T Niuhetang Formation volcanic rock is formed in the inner part of plate in this are- a, belonging to the inland tension volcanic rock.

关 键 词：晚三叠世火山岩 陆内拉张型 云南镇康 

分 类 号：P588.14[天文地球—岩石学]