Magnetic study of mafic granulite xenoliths from the Hannuoba basalt, north China

doi:10.1029/2008GC001952

	Magnetic study of mafic granulite xenoliths from the Hannuoba basalt, north China
	Liu, Qingsheng 1; Liu, Qingsong 2; Liu, Yongsheng 3; Gao, Shan 3,4; Yang, Tao 1; Luo, Yinhe 1; Jin, Zhenmin 3
刊名	GEOCHEMISTRY GEOPHYSICS GEOSYSTEMS
	2008-06-21
卷号	9
关键词	mafic granulite xenolith rock magnetism opaque mineralogy fractional crystallization Hannuoba north China
ISSN号	1525-2027
DOI	10.1029/2008GC001952
文献子类	Article
英文摘要	[1] The composition and structure of the lower continental crust are of great interest in understanding the dynamic processes of the Earth interior. In this study, we examined relationships between the magnetic properties and opaque mineralogy of a set of mafic granulite xenoliths ( derived from similar to 24-41 km) collected from the Hannuoba region, north China ( a region well known for its exposures of lower crustal rocks). These mafic granulite xenoliths are weakly magnetic with an average magnetic susceptibility ( c, mass specific) and saturation isothermal remanent magnetization ( SIRM) of 5.87 x 10(-7) m(3)kg(-1) and 31.53 x 10(-4) Am-2 kg(-1), respectively. The opaque minerals identified by electron microprobe (EMP) analysis in mafic granulite xenoliths are mainly paramagnetic Mg-rich ilmenite, which significantly contributed the room temperature c. In contrast, SIRM are controlled predominately by pyrrhotite and magnetite, which were clearly identified by both scanning electron microscopy (SEM) and rock magnetic analyses. Our results show some relationships between these magnetic properties and the ratio of concentrations of the trace rare earth elements (La/Yb), which is sensitive to degree of fractional crystallization. More significantly, the Mg content in ilmenite is highly related to the fractional crystallization. These observations bring new insights into the complexities of the magnetic properties and the mineral composition ( e. g., ilmenite) during the dynamic processes of mafic granulite xenoliths formation. However, the exact relationship between the rock magnetism and the fractional crystallization process needs further studies.
WOS关键词	LOWER CONTINENTAL-CRUST ; HEMATITE-ILMENITE SERIES ; UPPER-MANTLE XENOLITHS ; TRACE-ELEMENTS ; GRAIN-SIZE ; REMANENT MAGNETIZATION ; LAMELLAR MAGNETISM ; ROCK MAGNETISM ; CROSS-SECTION ; IVREA ZONE
WOS研究方向	Geochemistry & Geophysics
语种	英语
出版者	AMER GEOPHYSICAL UNION
WOS记录号	WOS:000257049700001
内容类型	期刊论文
源URL	[http://ir.iggcas.ac.cn/handle/132A11/68814]
专题	中国科学院地质与地球物理研究所
通讯作者	Liu, Qingsheng
作者单位	1.China Univ Geosci, Dept Geophys, Wuhan 430074, Peoples R China 2.Chinese Acad Sci, Paleomagnetism & Geochronol Lab SKL LE, Inst Geol & Geophys, Beijing 100029, Peoples R China 3.China Univ Geosci, State Key Lab Geol Proc & Mineral Resources China, Wuhan 430074, Peoples R China 4.NW Univ Xian, State Key Lab Continental Dynam, Xian 710069, Peoples R China
推荐引用方式 GB/T 7714	Liu, Qingsheng,Liu, Qingsong,Liu, Yongsheng,et al. Magnetic study of mafic granulite xenoliths from the Hannuoba basalt, north China[J]. GEOCHEMISTRY GEOPHYSICS GEOSYSTEMS,2008,9.
APA	Liu, Qingsheng.,Liu, Qingsong.,Liu, Yongsheng.,Gao, Shan.,Yang, Tao.,...&Jin, Zhenmin.(2008).Magnetic study of mafic granulite xenoliths from the Hannuoba basalt, north China.GEOCHEMISTRY GEOPHYSICS GEOSYSTEMS,9.
MLA	Liu, Qingsheng,et al."Magnetic study of mafic granulite xenoliths from the Hannuoba basalt, north China".GEOCHEMISTRY GEOPHYSICS GEOSYSTEMS 9(2008).