摘要
冈底斯南缘泽当地区林子宗群典中组火山岩极为发育。文章根据泽当地区典中组火山岩地质特征,结合地质剖面测制和岩石学、矿物学研究,对火山岩相和火山机构进行分类,将典中组火山岩分为爆发相、溢流相、火山通道相、过渡相和火山沉积相。根据火山活动喷发旋回特征,将研究区典中组火山作用分为下亚旋回和上亚旋回,下亚旋回包含3个喷发期次,4个喷发韵律,上亚旋回包含3个喷发期次、6个喷发韵律。根据火山岩岩性组合、岩相特征及其相互叠置关系,在研究区识别出1个破火山机构,2个层状火山机构,即结巴乡东破火山机构、多颇章西层状火山机构和擦结日层状火山机构。
Volcanic rocks of the Dianzhong formation of the Linzizong group are well developed in the Zedang area on the southern margin of Gangdese.According to the geological characteristics of the volcanic rocks of the Dianzhong formation in Zedang area,combined with geological profile measurement and petrological and mineralogical studies,this paper classifies the volcanic facies and volcanic bodies,and divides the volcanic rocks of the Dianzhong formation into explosive facies,overflow facies,volcanic channel facies,transitional facies and volcanic sedimentary facies.According to the characteristics of volcanic eruption cycles,the volcanism of Dianzhong formation in the study area is divided into lower subcycle and upper subcycle.The lower subcycle contains 3 eruption periods and 4 eruption rhythms,and the upper subcycle contains 3 eruption periods and 6eruption rhythms.According to the lithologic association,lithofacies characteristics and their overlapping relationship of volcanic rocks,one volcanic breaking mechanism and two layered volcanic mechanisms are identified in the study area,East volcanic breaking mechanism in Jieba Township,West layered volcanic mechanism in duopozhang and Cajieri layered volcanic mechanism.
作者
晏齐胜
张志平
汪宏涛
曹勇刚
包国志
YAN Qi-sheng;ZHANG Zhi-ping;CAO Yong-gang;LI Peng-ju;BAO Guo-zhi(The Third Institute of Geology and Minerals Exploration,Gansu Provincial Bureau of Geology and Minerals Exploration and Development,Lanzhou 730050,China;Gansu Sub-Center of Green Evaluation and Research Center of Mineral Resources,China Geological Survey,Lanzhou 730050,China)
出处
《甘肃地质》
2022年第3期13-23,共11页
Gansu Geology
基金
中国地质调查局西藏乃东县地区H46E016008、H46E017007、H46E017008幅1∶5万区域地质调查(DD20160015-08)项目
关键词
冈底斯南缘
泽当地区
典中组
火山岩相
火山机构
西藏
South Rim of the Gangdise
Zedang area
Dianzhong Formation
volcanic facies
volcanic edifice
