觉罗塔格地区下石炭统雅满苏组火山岩地球化学特征及其构造意义  

Geochemical Characteristics and Tectonic Significance of Volcanic Rocks of the Lower Carboniferous Yamansu Formation in the Jueluotage Area

作　　者：木扎帕尔·木合塔尔 宫相宽 尼加提·阿布都逊 Muzhapaer·Muhetaer;Gong XiangKuan;Nijiati·Abuduxun(College of Geology and Mining Engineering,Xinjiang University,Urumqi,Xinjiang,830046,China;Xinjiang Key Laboratory for Geodynamic Processes and Metallogenic Prognosis of the Central Asian Orogenic Belt,Urumqi,Xinjiang,830046,China)

机构地区：[1]新疆大学地质与矿业工程学院,新疆乌鲁木齐830046 [2]新疆大学中亚造山带大陆动力学与成矿预测自治区重点实验室,新疆乌鲁木齐830046

出　　处：《新疆地质》2020年第1期1-8,共8页Xinjiang Geology

基　　金：国家自然科学基金(41962013、41562010);新疆维吾尔自治区自然科学基金(2016D01C082、2019D01C030)联合资助。

摘　　要：本文对觉罗塔格地区雅满苏组火山岩全岩地球化学进行了系统研究并比对前人数据,结果显示这些岩石主体富集大离子亲石元素Rb,Ba,Th和U,亏损高场强元素Nb,Ta,类似于岛弧火山岩。对比发现玄武岩可分为两类,I类玄武岩微量和稀土元素含量较低,轻重稀土元素分馏不明显,具亏损地幔特征;Ⅱ类玄武岩稀土和微量元素含量较高,具大陆玄武岩特征,显示出它们来自不同的岩浆源区;中酸性火山岩浆主要由新生陆壳部分熔融而成,安山岩、英安岩和流纹岩为同源岩浆演化不同阶段的产物,并在岩浆演化过程中经历幔源组分混染。结合区域地质背景资料,认为觉罗塔格地区晚古生代期间发生了洋壳的双向俯冲作用。In this paper,the whole rock geochemistry of the volcanic rock of the yamansu formation in zhuorotag region is systematically studied and compared with the previous data.Rock geochemical analysis shows that these rocks are rich in large ion lithophilic elements Rb,Ba,Th and U,and depleted in high field strength elements Nb and Ta,similar to island arc volcanic rocks.Basalts can be divided into two types,Class I basalt has relatively low contents of trace and rare earth elements,and the fractionation of light and heavy rare earth elements is not obvious,which shows the characteristics of deficient mantle,while classⅡbasalt has relatively high contents of rare earth and trace elements,which shows the characteristics of continental basalt,they come from different magma source areas;intermediate-acidic volcanic magma is mainly formed by partial melting of the new continental crust;andesite,dacite and rhyolite are products of different stages of the same magma evolution,and undergo contamination of mantle-derived components in the process of magma evolution.Combined with the regional geological background data,it is considered that the oceanic crust was subducted in two directions during the Late Paleozoic in Jueluotage area.

关 键 词：觉罗塔格地区 石炭纪 雅满苏组火山岩 岛弧环境 地球化学 

分 类 号：P588.14[天文地球—岩石学] P597[天文地球—地质学]