中国地质2013，Vol.40Issue(4)：1007-1015,9.
扬子西缘黄水河群玄武岩锆石SHRIMP U-Pb定年及其地质意义
Zircon SHRIMP U-Pb dating of basalt from Huangshuihe Group on the western margin of the Yangtze block and its geological significance
摘要
Abstract
The structural clip of Huangshuihe Group,distributed along Longmenshan thrust nappe belt,is one of the typical low-grade metamorphic rock series,and some metamorphism could reach amphibolite facies,with the wide distribution of volcanic rocks.Based on field geological survey in combination with petrologic and petrographic analysis,the authors collected a sample of basalt from Ganheba Formation for zircon SHRIMP U-Pb dating,and obtained two U-Pb 206Pb/238U weighted average ages of (799±8) Ma (MSWD=0.96) and (875±12) Ma (MSWD=0.38).The former age of (799±8)Ma represents the crystallization age of the basalt,suggesting Mid-Neoproterozoic,whereas the latter represents the age of captured zircon,signifying a tectonic-magmatic event of Jinning movement.Combined with the results of data obtained from the region,the authors hold that Huangshuihe Group,Yanjing Group,and Suxiong Formation were contemporary sedimentary strata formed in the late Qingbaikou period.关键词
黄水河群/玄武岩/锆石SHRIMP定年/扬子西缘/新元古代中期Key words
Huangshuihe Group/basalt/zircon U-Pb dating/western margin of Yangtze block/Mid-Neoproterozoic分类
天文与地球科学引用本文复制引用
任光明,庞维华,孙志明,尹福光..扬子西缘黄水河群玄武岩锆石SHRIMP U-Pb定年及其地质意义[J].中国地质,2013,40(4):1007-1015,9.基金项目
国家自然科学基金重点项目(41030315)、中国地质调查局调查项目(1212011121110和1212011085147)及国土资源大调查项目(1212010610213)资助. （41030315）
