Effects of multi-stage rifting and metasomatism on HSE-Os-187/Os-188 systematics of the cratonic mantle beneath SW Greenland

doi:10.1007/s00410-019-1549-7

CORC > 地质与地球物理研究所 > 中国科学院地质与地球物理研究所 > 岩石圈演化国家重点实验室

	Effects of multi-stage rifting and metasomatism on HSE-Os-187/Os-188 systematics of the cratonic mantle beneath SW Greenland
	Aulbach, Sonja 1; Sun, Jing 2; Tappe, Sebastian 3; Gerdes, Axel 1
刊名	CONTRIBUTIONS TO MINERALOGY AND PETROLOGY
	2019-02-01
卷号	174 期号:2 页码:23
关键词	Subcontinental lithosphere Mantle metasomatism Platinum-group elements Highly siderophile elements Base metal sulphides
ISSN号	0010-7999
DOI	10.1007/s00410-019-1549-7
英文摘要	We report highly siderophile element (HSE) abundances and Re-Os isotope compositions, obtained by isotope dilution inductively coupled plasma mass spectrometry, of olivine separates from a suite of multiply metasomatised peridotite xenoliths entrained in kimberlites from SW Greenland. Combined with petrographic and compositional observations on accessory base metal sulphides (BMS), the results reveal new insights into the chemical, physical and mineralogical effects of multi-stage rifting and associated melt percolation on the Archaean lithospheric mantle. Refertilised lherzolites are dominated by rare to frequent small (tens of mu m) BMS inclusions in olivine, whereas modally metasomatised phlogopite-bearing lherzolite and wehrlites have higher proportions of more Ni-rich BMS, including abundant large interstitial grains (hundreds of mu m). The olivine separates display depleted HSE systematics with Primitive Upper Mantle (PUM)-normalised Pd/Ir of 0.014-0.62, and have both depleted and enriched Os-187/Os-188 (0.1139-0.2724) relative to chondrite that are not correlated with Re-187/Os-188. Four out of ten olivine separates retain similarly depleted Os corresponding to Re-depletion model ages of 2.1-1.8Ga. They may reflect Palaeoproterozoic refertilisation (lherzolitisation) during Laurentia plate assembly, with re-introduction of clinopyroxene and Os-rich BMS into the originally refractory mantle lithosphere by asthenosphere-derived basaltic melts, followed by recrystallisation and occlusion in olivine. Unradiogenic Os is observed regardless of lithology, including from peridotites that contain abundant interstitial BMS. This reflects addition of Os-poor BMS (<<1ppm) during more recent wehrlitisation and phlogopite-introduction, and control of the Os isotopic signature by older Os-rich BMS that precipitated from the basaltic melt. Depletions in compatible HSE (<0.5xPUM for Ru, Ir, Os) in all but one olivine separate reflect nugget effects (amount of depleted vs. metasomatic BMS inclusions) and/or loss due to sulphide dissolution into oxidising small-volume melts that invaded the lithosphere during recurrent rifting, the latter supported by similar depletions in published bulk peridotite data. Combined, these multiple metasomatic events destroyed all vestiges of Mesoarchaean or older inheritance in the olivine separates investigated here, and highlight that caution is needed when interpreting Proterozoic Os model ages in terms of Proterozoic lithosphere stabilisation.
资助项目	German Research Foundation (DFG)[GE1152/9] ; German Academic Exchange Service (DAAD) ; Geological Survey of Denmark and Greenland ; DST-NRF CIMERA Centre of Excellence at the University of Johannesburg, South Africa
WOS关键词	PLATINUM-GROUP ELEMENTS ; HIGHLY SIDEROPHILE ELEMENTS ; NORTH-ATLANTIC CRATON ; VOLATILE-RICH METASOMATISM ; LITHOSPHERIC MANTLE ; WEST GREENLAND ; RE-OS ; ISOTOPIC COMPOSITIONS ; PERIDOTITE XENOLITHS ; SULFIDE SATURATION
WOS研究方向	Geochemistry & Geophysics ; Mineralogy
语种	英语
出版者	SPRINGER
WOS记录号	WOS:000457712600002
资助机构	German Research Foundation (DFG) ; German Research Foundation (DFG) ; German Academic Exchange Service (DAAD) ; German Academic Exchange Service (DAAD) ; Geological Survey of Denmark and Greenland ; Geological Survey of Denmark and Greenland ; DST-NRF CIMERA Centre of Excellence at the University of Johannesburg, South Africa ; DST-NRF CIMERA Centre of Excellence at the University of Johannesburg, South Africa ; German Research Foundation (DFG) ; German Research Foundation (DFG) ; German Academic Exchange Service (DAAD) ; German Academic Exchange Service (DAAD) ; Geological Survey of Denmark and Greenland ; Geological Survey of Denmark and Greenland ; DST-NRF CIMERA Centre of Excellence at the University of Johannesburg, South Africa ; DST-NRF CIMERA Centre of Excellence at the University of Johannesburg, South Africa ; German Research Foundation (DFG) ; German Research Foundation (DFG) ; German Academic Exchange Service (DAAD) ; German Academic Exchange Service (DAAD) ; Geological Survey of Denmark and Greenland ; Geological Survey of Denmark and Greenland ; DST-NRF CIMERA Centre of Excellence at the University of Johannesburg, South Africa ; DST-NRF CIMERA Centre of Excellence at the University of Johannesburg, South Africa ; German Research Foundation (DFG) ; German Research Foundation (DFG) ; German Academic Exchange Service (DAAD) ; German Academic Exchange Service (DAAD) ; Geological Survey of Denmark and Greenland ; Geological Survey of Denmark and Greenland ; DST-NRF CIMERA Centre of Excellence at the University of Johannesburg, South Africa ; DST-NRF CIMERA Centre of Excellence at the University of Johannesburg, South Africa
内容类型	期刊论文
源URL	[http://ir.iggcas.ac.cn/handle/132A11/90521]
专题	地质与地球物理研究所_岩石圈演化国家重点实验室
通讯作者	Aulbach, Sonja
作者单位	1.Goethe Univ, Inst Geowissensch, Altenhoferallee 1, D-60438 Frankfurt, Germany 2.Chinese Acad Sci, Inst Geol & Geophys, State Key Lab Lithospher Evolut, Beijing 100029, Peoples R China 3.Univ Johannesburg, Dept Geol, POB 524, ZA-2006 Auckland Pk, South Africa
推荐引用方式 GB/T 7714	Aulbach, Sonja,Sun, Jing,Tappe, Sebastian,et al. Effects of multi-stage rifting and metasomatism on HSE-Os-187/Os-188 systematics of the cratonic mantle beneath SW Greenland[J]. CONTRIBUTIONS TO MINERALOGY AND PETROLOGY,2019,174(2):23.
APA	Aulbach, Sonja,Sun, Jing,Tappe, Sebastian,&Gerdes, Axel.(2019).Effects of multi-stage rifting and metasomatism on HSE-Os-187/Os-188 systematics of the cratonic mantle beneath SW Greenland.CONTRIBUTIONS TO MINERALOGY AND PETROLOGY,174(2),23.
MLA	Aulbach, Sonja,et al."Effects of multi-stage rifting and metasomatism on HSE-Os-187/Os-188 systematics of the cratonic mantle beneath SW Greenland".CONTRIBUTIONS TO MINERALOGY AND PETROLOGY 174.2(2019):23.