地质论评2018，Vol.64Issue(1)：127-140,14.DOI:10.16509/j.georeview.2018.01.009
北秦岭早古生代宽坪岩体两期花岗质岩浆锆石U-Pb年代学、地球化学及其地质意义
Zircon U-Pb Ages and Geochemical Characteristics of the Two-stage Granitic Magamtism from the Kuanping Pluton in the Northern Qinling Mountains: Petrogenesis and Tectonic Implication
摘要
Abstract
Objectives:The Early Paleozoic Kuanping granite pluton in Danfeng area have important geological significance for constraining the tectonic evolution of the Qinling Mountains.Kuanping granite pluton is composed by gneissic biotite monzogranite and porphyraceous biotite granite.Methods:Based on the field work,through the microscope observation,the whole rock chemical analysis,the ziron LA-ICP MS U-Pb dating of the gneissic biotite monzogranite and porphyraceous biotite monzogranite.Results:The gneissic biotite monzogranite and porphyraceous biotite monzogranite have ages of 448.3 4.5Ma and 421.4 2.5Ma respectively.The gneissic biotite monzogranite display high SiO2 and (Na2O+K2O) contents,they belong to metaluminous and high-K calc-alkaline series,it is considered to be formed by fluxing melting of plagioclase-poor pelitic rocks in middle—upper crust.The porphyraceous biotite granite is peraluminous,they are considered to be formed by dehydration melting of metagerywacks or granitic gnesis in middle—lower crust.Conclusions:The geochemical evolution of the Paleozoic granites in the northern Qinling from 450 to 420Ma reveals a tectonic evolution from syn-collisional to post-collisional process.关键词
LA-ICP-MS锆石U-Pb年龄/地球化学/北秦岭/宽坪岩体/早古生代Key words
LA-ICP-MS zircon dating/geochemistry/north Qingling Mts/Kuanping pluton/early Paleozoic引用本文复制引用
王江波,秦江锋,胡鹏,张良,赵友东,张泽中..北秦岭早古生代宽坪岩体两期花岗质岩浆锆石U-Pb年代学、地球化学及其地质意义[J].地质论评,2018,64(1):127-140,14.基金项目
本文为国家自然科学基金资助项目(编号:41421002、41102037)、中国地质调查局地质矿产调查项目(编号:DD2016013623)、中国核工业地质局铀矿地质项目(编号:201621、201572)、陕西省青年科技新星专项(编号:2014KJXX-60、2017KJXX-94)和全国优秀博士论文作者专项资助(编号:201324)的成果.This study is financially supported by China geological survey(No.DD2016013623),China nuclear geology(No.201621,201572),Shaanxi science and technology department(No.2014KJXX-60,2017KJXX-94),the foundation for the author of national excellent doctoral dissertation of China(No.201324) and the National Natural Science Foundation of China(No.41421002,41102037). （编号:41421002、41102037）
