地质通报2012，Vol.31Issue(12)：1949-1964,16.
中天山南缘那拉提碱性花岗岩岩石成因——来自锆石微量元素和Hf同位素的证据
Petrogenesis of Nalati alkali granites in South Central Tianshan Mountains:Evidence from zircon trace elements and Hf isotope
摘要
Abstract
Lying in South Central Tianshan Mountains, the Early-Permian Nalati granites intruded into Silurian strata. The zircons of the Nalati granites all have well-developed oscillatory growth zoning in cathodoluminescence images and high Th/U ratios. Some of the zircons show typical REE patterns, which are similar to characteristics of the magmatic zircons, and the other zircons with low Ce/ Ce * ratios might have been formed in a low-fO2 environment, and their high (La/Sm)N ratios should be related to the influence of inclusions rather than to that of the meta—fluid. The chemical features of low Sr and high Yb, and high zircon saturation temperatures indicate that they were formed in a normal or decompression environment. The analyzed domains of zircons have high 176Hf/177Hf ratios and positive εHt(t) values, and the zircon second-stage Hf model ages are older than the crystallization ages of granites. The above evidence suggests that Nalati granites were the melted product of juvenile crust in Permian. Combined with previous researches on granites in thus region and petrogenesis of Neopaleozoic volcanic rocks, the authors have reached the conclusion that the Nalati granites are geological records of Carboniferous and Permian magmatic activities in an intense lithosphere extension process in China's Tianshan region.关键词
中天山南缘/晚古生代/花岗岩岩石成因/锆石Hf同位素Key words
the South Central Tianshan/Late Paleozoic/petrogenesis of granites/Hf isotope分类
天文与地球科学引用本文复制引用
李平,徐学义,王洪亮,朱涛,万晓明..中天山南缘那拉提碱性花岗岩岩石成因——来自锆石微量元素和Hf同位素的证据[J].地质通报,2012,31(12):1949-1964,16.基金项目
国家自然科学基金项目《西天山西南缘那拉提段古生代花岗岩成因对天山洋陆转换的制约》(批准号:40872061)、中国地质调查局地质矿产调查评价项目《西北地区基础地质调查成果集成与综合研究》(编号:1212011220649和《天山成矿带基础地质综合研究》(编号:1212011085055) （批准号:40872061）
