摘要
阿尔泰北部大面积出露的喀纳斯群为一套巨厚的浅变质陆缘碎屑岩,本次工作系统采集了锆石同位素年龄样品及岩石地球化学样品,其地球化学分析结果显示沉积物来源于被动大陆边缘环境;获得的碎屑锆石U-Pb同位素年龄资料中,最年轻的岩浆锆石年龄为（545.8±3.7）Ma,据此可将喀纳斯群的底界定为震旦系;较老的元古代锆石年龄（858±13 Ma及1 800~1 983Ma）暗示了物源区很可能存在前寒武纪大陆地壳基底。
The Kanas Group is consists of thick epimetamorphic terrigenous clasolite,which occurs widely in northern Altay.In this paper,the samples of zircon isotopic dating and rock geochemicalanalysis have been collected systematically.The geochemical results show that these clasticsedimentaries were sourced from passive continental margin.The U-Pb dating of detrital Zircon from the Kanas Group yield the youngest magmatic Zircon age of 545.8±3.7Ma,defining that the lower boundary of the Kanas Group can be delimit as Sanian.But the older Zircon ages are 858±13 Ma and 1 800-1 983 Ma,which belong to Proterozoic era,indicating the existence of Precambrian continental crust basement.
出处
《西北地质》
CAS
CSCD
2016年第3期13-27,共15页
Northwestern Geology
基金
基金项目:中国地质调查局“阿尔泰成矿带喀纳斯和东准地区地质矿产调查”(121201011000150003)
