摘要
在简要介绍Fe同位素体系的基础上,对Fe同位素在地幔地球化学研究中的应用进行了较为系统的评述。根据华北克拉通新生代玄武岩及其携带的地幔捕虏体Fe同位素研究最新进展和国际上已发表的有关数据,总结了Fe同位素在大洋玄武岩,地幔捕虏体及其单矿物中的分布特征。统计结果表明,来自世界不同地区的大洋玄武岩的Fe同位素组成比较均一,并且相对地幔橄榄岩Fe同位素组成总体偏重,表明地幔部分熔融过程导致Fe同位素分馏。而地幔捕虏体及其单矿物的Fe同位素组成明显不均一。没有受到地幔交代作用影响的橄榄岩,Fe同素组成变化范围小,而经受不同类型地幔交代作用影响的地幔橄榄岩,Fe同位素组成存在明显的差异,这说明地幔交代作用是导致地幔Fe同位素组成不均一的重要机制。
Following a brief introduction of the Fe isotopic system,this paper has reviewed the achievements of its applica-tions in the mantle geochemical researches obtained in recent years.Based on the iron isotopic data of Neozoic basalts and their coexited mantle xenoliths from the North China Craton and worldwide published in recent years,a review on distribu-tion characteristics of iron isotopes of ocenic basalts,mantle xenoliths and their rock-forming minerals has been given in this paper.The result shows that oceanic basalts from various areas worldwide have relatively consistent iron isotopic com-positions with their δ57 Fe values relatively higher than that of the peridotite,indicating that there is iron isotope fractiona-tion in the mantle partial melting process.In contrast,mantle xenoliths and their ore-forming minerals obviously have heter-ogeneous iron isotopic compositions.The un-metasomatised peridotites have relatively homogeneous Fe isotopic composi-tions,whereas various kinds of metasomatised peridotites display obviously different Fe isotopic compositions.These char-acteristics suggest that the mantle metasomatism could be significantly resulted in the the heterogeneity of Fe isotopes of va-rious metasomatised lithospheric mantle.
作者
曹辉辉
赵新苗
张宏福
CAO Hui-hui ZHAO Xin-miao ZHANG Hong-fu(State Key Laboratory of Lithospheric Evolution, Institute of Geology and Geophysics, Chinese Academy of Sciences, Beifing 100029, China University of Chinese Academy of Sciences, Beijing 100049, China State Key Laboratory of Continental Dynamics, Department of Geology, Northwest University, Xi＇an 710069)
出处
《矿物岩石地球化学通报》
CAS
CSCD
北大核心
2016年第5期1053-1064,共12页
Bulletin of Mineralogy, Petrology and Geochemistry
基金
国家自然科学基金项目(41173044
41373041)
国家自然科学基金重大项目(91014007)
