Early differentiation of the bulk silicate Earth as recorded by the oldest mantle reservoir

doi:10.1016/j.precamres.2013.09.010

	Early differentiation of the bulk silicate Earth as recorded by the oldest mantle reservoir
	Wang, Xuan-Ce 1; Li, Zheng-Xiang 1; Li, Xian-Hua 2
刊名	PRECAMBRIAN RESEARCH
	2013-11-01
卷号	238 页码:52-60
关键词	Baffin Bay picrite Chemical heterogeneity Ancient mantle reservoir Early silicate Earth's differentiation Melt density contrast Magma ocean
ISSN号	0301-9268
DOI	10.1016/j.precamres.2013.09.010
文献子类	Article
英文摘要	An emerging challenge for understanding the Earth system is to determine the relative roles of early planetary processes versus progressive differentiation in shaping the Earth's chemical architecture. An enduring tenet of modern chemical geodynamics is that the Earth started as a well-mixed and homogeneous body which evolved progressively over the geologic time to several chemically distinct domains. As a consequence, the observable chemical heterogeneity in mantle-derived rocks has generally been attributed to the Earth's dynamic evolution over the past 4.5 Ga. However, the identification of chemical heterogeneity formed during the period 4.53-4.45 Ga in the ca. 60 Ma Baffin Bay high-magnesium lavas provides strong evidence that chemical effects of early differentiation can persist in mantle reservoirs to the present day. Here, we demonstrate that such an ancient mantle reservoir is likely composed of enriched and depleted dense melts, and propose a model for early global differentiation of the bulk silicate Earth that would produce two types of dense melts with distinctive chemical compositions in the deep Earth. These dense melts ultimately became parts of the thermo-chemical piles near the core-mantle boundary that have been protected from complete entrainment by subsequent mantle convection currents. We argue that although such dense melts likely exhibit some 'primordial' geochemical signatures, they are not representative of the bulk silicate Earth. Our work provides a strong case for the mantle chemical heterogeneity being formed by a major differentiation event shortly after planet accretion rather than through the subsequent geodynamic evolution. (C) 2013 Elsevier B.V. All rights reserved.
WOS关键词	RHENIUM-OSMIUM ISOTOPE ; BAFFIN-ISLAND PICRITES ; TRACE-ELEMENT ; OCEANIC-CRUST ; DEEP MANTLE ; WEST GREENLAND ; HADEAN MANTLE ; SOURCE REGION ; CHEMICAL GEODYNAMICS ; TERRESTRIAL PLANETS
语种	英语
出版者	ELSEVIER SCIENCE BV
WOS记录号	WOS:000330818800004
资助机构	National Science Foundation of China(41173038 ; National Science Foundation of China(41173038 ; Australian Research Council (ARC) ESTAR Fellowship through the ARC Centre of Excellence for Core to Crust Fluid Systems (CCFS) ; Australian Research Council (ARC) ESTAR Fellowship through the ARC Centre of Excellence for Core to Crust Fluid Systems (CCFS) ; 41373020) ; 41373020) ; National Science Foundation of China(41173038 ; National Science Foundation of China(41173038 ; Australian Research Council (ARC) ESTAR Fellowship through the ARC Centre of Excellence for Core to Crust Fluid Systems (CCFS) ; Australian Research Council (ARC) ESTAR Fellowship through the ARC Centre of Excellence for Core to Crust Fluid Systems (CCFS) ; 41373020) ; 41373020) ; National Science Foundation of China(41173038 ; National Science Foundation of China(41173038 ; Australian Research Council (ARC) ESTAR Fellowship through the ARC Centre of Excellence for Core to Crust Fluid Systems (CCFS) ; Australian Research Council (ARC) ESTAR Fellowship through the ARC Centre of Excellence for Core to Crust Fluid Systems (CCFS) ; 41373020) ; 41373020) ; National Science Foundation of China(41173038 ; National Science Foundation of China(41173038 ; Australian Research Council (ARC) ESTAR Fellowship through the ARC Centre of Excellence for Core to Crust Fluid Systems (CCFS) ; Australian Research Council (ARC) ESTAR Fellowship through the ARC Centre of Excellence for Core to Crust Fluid Systems (CCFS) ; 41373020) ; 41373020)
内容类型	期刊论文
源URL	[http://ir.iggcas.ac.cn/handle/132A11/87347]
专题	中国科学院地质与地球物理研究所
通讯作者	Wang, Xuan-Ce
作者单位	1.Curtin Univ, Dept Appl Geol, Inst Geosci Res TIGeR, ARC Ctr Excellence Core Crust Fluid Syst CCFS, Perth, WA 6845, Australia 2.Chinese Acad Sci, Inst Geol & Geophys, State Key Lab Lithospher Evolut, Beijing 100029, Peoples R China
推荐引用方式 GB/T 7714	Wang, Xuan-Ce,Li, Zheng-Xiang,Li, Xian-Hua. Early differentiation of the bulk silicate Earth as recorded by the oldest mantle reservoir[J]. PRECAMBRIAN RESEARCH,2013,238:52-60.
APA	Wang, Xuan-Ce,Li, Zheng-Xiang,&Li, Xian-Hua.(2013).Early differentiation of the bulk silicate Earth as recorded by the oldest mantle reservoir.PRECAMBRIAN RESEARCH,238,52-60.
MLA	Wang, Xuan-Ce,et al."Early differentiation of the bulk silicate Earth as recorded by the oldest mantle reservoir".PRECAMBRIAN RESEARCH 238(2013):52-60.