An in situ zircon Hf isotopic,U-Pb age and trace element study of banded granulite xenolith from Han

来源 :Chinese Science Bulletin | 被引量 : 0次 | 上传用户:majixiong0
下载到本地 , 更方便阅读
声明 : 本文档内容版权归属内容提供方 , 如果您对本文有版权争议 , 可与客服联系进行内容授权或下架
论文部分内容阅读
Backscattered electron images, in situ Hf isotopes, U-Pb ages and trace elements of zircons in a banded granulite xenolith from Hannuoba basalt have been studied. The results show that the banded granulite is a sample derived from the early lower crust of the North China craton. It is difficult to explain the petrogenesis of the xenolith with a single process. Abundant information on several processes, however, is contained in the granulite. These processes in-clude the addition of mantle material, crustal remelting, metamorphic differentiation and the delamination of early lower crust. About 80% of zircons studied yield ages of 1842 ±40 Ma, except few ages of 3097-2824 Ma and 2489-2447 Ma. The zircons with ages older than 2447 Ma have high εHf (up to +18.3) and high Hf model age (2.5-2.6 Ga), indicating that the primitive materials of the granulite were derived mainly from a depleted mantle source in late Archean. Most εhf of the zircons with early Proterozoic U-Pb age vary around zero, but two have Backscattered electron images of in situ Hf isotopes, U-Pb ages and trace elements of zircons in a banded granulite xenolith from Hannuoba basalt have been studied. The results show that the banded granulite is a sample derived from the early lower crust of the North China It is difficult to explain the petrogenesis of the xenolith with a single process. However, these are in to cite the addition of mantle material, crustal remelting, metamorphic differentiation and the delamination of early lower crust. About 80% of zircons studied yield ages of 1842 ± 40 Ma, except few ages of 3097-2824 Ma and 2489-2447 Ma. The zircons with ages older than 2447 Ma have high εHf (up to +18.3) and high Hf model age (2.5-2.6 Ga), indicating that the primitive materials of the granulite were derived mainly from a depleted mantle source in late Archean. Most εhf of the zircons with early Proterozoic U-Pb age vary around zero, but two have
其他文献
圣经译本是在“人的语言”里之“神的话”。英语译本比较的结果显示,在新约的一些经文中,πvεuμa并不单指神的灵或人的灵,而是指神灵与人灵的结合或搀调。所以,若一定要在S
本文首先对物联网技术专业建设的现状做了具体分析,然后结合具体实例阐述了专业建设的主要成效,并作了经验总结,同时指出目前自身存在的一些问题和困难,并进一步提出具体解决
当前,中职学校主要是培养技能型人才为主,但是近年来,我国的中职院校存在着很多突出的问题,如生源质量较差、学生不服从管理、学生的德育素质较低等。在经济科技飞速发展的今
2011年,江苏省根据《江苏省中长期教育改革和发展规划纲要(2010-2020年)》对省内高职院校试行面向中职毕业生的注册入学,顺应了教育的改革和发展趋势,对扩大高职院校招生自主
本文介绍了内业资料处理中野外定位数据的提取、转换及如何利用AutoCAD绘图软件快速绘制站位图件的方法。 This article describes the field of data processing in the fi
巴基斯坦北Potwar形变区是西北喜马拉雅褶皱逆冲带前陆区的一部分 ,绘制了该区的地震活动性图 .与相邻地区比较 ,该区地震并不活跃 ,没有显示出与地表地质构造相关的清晰地震
肿瘤是目前严重危害人类健康的一类疾病。研究发现,癌基因的活化和抑癌基因的失活使细胞周期调节失控是肿瘤发生发展中的重要因素。对细胞周期及其调节因子在肿瘤发生发展中
设想了一种两个自由度的滑块—弹簧模型,其中的2个滑块(滑块1和滑块2)由一根弹簧连接,并由一个慢慢移动的传动装置驱动。假设采用与速率和状态相关的摩擦定律,设定摩擦参数,
《职业学校学生技能抽测实践与改进研究》是江苏省职业技术教育学会立项课题。本文就淮安市专业技能抽测现状及存在问题进行了论述和分析,并提出了改进建议。 “Vocational