地质论评2019，Vol.65Issue(1)：85-102,18.DOI:10.16509/j.georeview.2019.01.007
江南造山带石耳山新元古代花岗岩的构造变形、LA-ICP-MS锆石U-Pb年龄及其地质意义
Deformational Characteristics and LA-ICP-MS Zircon U-Pb Ages of Granites at Shiershan in the Jiangnan Orogen and Their Geological Significance
摘要
Abstract
Objectives: There are a large number of deformational granites at the junction of Anhui, Zhejiang, and Jiangxi province in the eastern part of the Jiangnan orogen. A lot of researches have been done by the isotope chronology and geochemistry on the granites. However, the structural deformation characteristics of the granites are little investigated. In this research, we focus on the deformational characteristics and geochronology of granites and their regional geological significant.Methods: On the basis of detailed field work, the structural analysis and LA-ICP-MS zircon U-Pb dating are carried out on the granites.Results: The granites distribute in NE direction and parallel to the northeastern Jiangxi deep-fracture zone. A lot of structures, such as foliation and mineral lineation of mylonite, rotated porphyroblast and S—C fabrics, indicated that the granites had been suffered ductile shearing. Meanwhile, widely developed of the remnants of early magma flow, myrmekite and solid plastic deformation truly recorded the process of semi-solid flow and deformation of the granites. The LA-ICP-MS zircon U-Pb dating results of two samples is 783 ± 14 Ma and 780 ± 12 Ma, indicating that formation of granites in this region is about at 780 Ma. These ages are in accordance with ages of regional metamorphic and deformation.Conclusion: The results show that the granites at the junction of Anhui, Zhejiang, and Jiangxi are syntectonic. They are affected by the ductile shearing in the process of magmatic emplacement—condensation. They are the products of the collision between Yangtze Plate and Cathaysian Plate.关键词
江南造山带/板块汇聚/同构造花岗岩/锆石U-Pb年龄Key words
Jiangnan orogenic belt/plate convergence/syntectonic granite/zricon U-Pb dating引用本文复制引用
王阳阳,李振强,宋传中,李加好,李振伟,袁芳,任升莲,林寿发,王微,葛延鹏..江南造山带石耳山新元古代花岗岩的构造变形、LA-ICP-MS锆石U-Pb年龄及其地质意义[J].地质论评,2019,65(1):85-102,18.基金项目
中国地质调查局项目(编号:DD20160082) （编号:DD20160082）
国家自然科学基金资助项目(编号:41272222)的成果 （编号:41272222）
