摘要
浙江章村地区中元古代双溪坞群火山岩是江南造山带的重要组成部分,下部北坞组以中基性至中酸性凝灰岩类为主,中部岩山组以沉凝灰岩类占优势,上部章村组以中酸性至酸性熔结凝灰岩类为特色,形成较完整的中基性-酸性火山岩演化序列。岩石化学和稀土元素、微量元素地球化学均指示其形成于岛弧环境,反映为大陆边缘岛弧挤压背景下同源岩浆连续分异过程中火山作用的产物,自下而上显示了岛弧逐步增大并不断成熟的过程。从所见物质成分分析,它经历了北坞期火山岛弧陆相喷发-岩山期火山间歇弧内盆地沉积-章村期火山岛弧陆相爆溢3个阶段,在经历了持续的火山活动之后,区内之龙门山岛弧处于挤压体制之中并褶皱造山,其起因与Rodinia超大陆发生聚合造山作用有关。
The volcanic rocks of the Shuangxiwu Group of Mesoproterozoic in Zhangcun, Zhejiang Province are the important part of the Jiangnan orogen. The Beiwu Group in the bottom mainly consists of intermediate-basic to intermediate-acid tuff, the Yanshan Group in the middle is made of sedimentary tuff, and the Zhangcun Group in the top consists mainly of the intermediate-acid and acid ignimbrites, which together compose a complete evolvement sequences from intermediate-basic to acid volcanic rocks. It is proved that they were formed in an island-arc environment by the evidence of petrochemistry and geochemistry of trace and rare elements, and the arc shows growing and maturing gradually from bottom to top. According to the analysis and survey results, it is concluded that the volcanic rock series of the Shuangxiwu Group maybe undergo the 3 processes. The first was Beiwu period of volcanic arc continental eruption, and the second was Yanshan period of the intermittent intra-arc basin sedimentation, and the third was Zhangcun period of continental volcanic arc extrusion and explosion. After the continuing volcanic activities, the Longmenshan island arc was undergone the compaction and folding orogeny, related to the Rodinia supercontinental assemblage orogeny.
出处
《吉林大学学报（地球科学版）》
EI
CAS
CSCD
北大核心
2009年第4期689-698,共10页
Journal of Jilin University：Earth Science Edition
基金
中国地质调查局地质大调查项目(200413000021)
关键词
双溪坞群火山岩
岛弧环境
地球化学
造山带
Rodinia超大陆聚合
中元古代
浙江章村
volcanic rock of Shuangxiwu Group
island arc setting
geochemistry
orogeny belt
Rodinia supercontinent assemblage
Mesoproterozoic
Zhangcun of Zhejiang Province
