干旱区生态环境知识资源中心(Arid): The effects of terrestrial weathering on samarium-neodymium isotopic composition of ordinary chondrites

Arid

DOI	10.1016/j.chemgeo.2020.120056
	The effects of terrestrial weathering on samarium-neodymium isotopic composition of ordinary chondrites
	Pourkhorsandi, Hamed; Debaille, Vinciane; Armytage, Rosalind M. G.; van Ginneken, Matthias; Rochette, Pierre; Gattacceca, Jerome
通讯作者	Pourkhorsandi, H (corresponding author), Univ Libre Bruxelles, Lab G Time, CP 160-02,50 Av FD Roosevelt, B-1050 Brussels, Belgium.
来源期刊	CHEMICAL GEOLOGY
ISSN	0009-2541
EISSN	1872-6836
出版年	2021
卷号	562
英文摘要	Following their fall to Earth, meteorites experience weathering. In this systematic study, we evaluate the trace element composition of ordinary chondrites from the Antarctic cold desert, and Atacama (Chile) and Lut (Iran) hot deserts, with an emphasis on rare earth elements (REE). Our data confirms that terrestrial weathering of meteorites in hot deserts changes their trace element (Sr, Ba, REE, Hf, Th, and U) concentrations. However, weathering effects in majority of Antarctic samples are limited to slight Ba, REE, Hf, and Th depletions and in some case to U enrichment. In comparison to the Antarctic meteorites, hot desert samples show greater disturbances and REE fractionation relative to the average fall values. We measured the Sm-Nd isotopic composition of the hot desert meteorites that have heavily affected REE compositions. Our Sm-Nd isotopic data show a significant effect of terrestrial weathering evidenced by non-CHUR Sm-147/Nd-144 and Nd-143/Nd-144 ratios. Measurements show a higher variation and lower values of Sm-147/Nd-144 for the Atacama samples than those from the Lut Desert. Deviations from CHUR Sm-147/Nd-144 value are in positive accordance with the degree of La/Lu fractionation caused by weathering. The epsilon Nd values of Atacama and Lut deserts meteorites range from -2.20 to +1.61, which is wider than the -1.07 to +0.64 range for falls. We suggest that disturbance of primary Sm/Nd ratios resulting from mixing with terrestrial components originating from soil during weathering is responsible for lower Sm-147/Nd-144 ratio in these meteorites. The majority of the Atacama meteorites regardless of their weathering degrees have their REE compositions and epsilon Nd affected by terrestrial contamination. Both Sm-147/Nd-144 ratio and epsilon Nd values show no straightforward relationship with weathering degree. However, in both cases the samples with the highest negative isotopic disturbances are H chondrites from the Atacama and Lut deserts. In addition, Ba concentration shows a negative correlation with Sm-147/Nd-144 ratio. Care must be taken into account while dealing with samples collected from hot deserts, even fresh-looking ones.
英文关键词	Sm-Nd Samarium-Neodymium Chondrite Weathering Hot desert Contamination
类型	Article
语种	英语
开放获取类型	Green Published
收录类别	SCI-E
WOS记录号	WOS:000615171000011
WOS类目	Geochemistry & Geophysics
WOS研究方向	Geochemistry & Geophysics
来源机构	French National Research Institute for Sustainable Development
资源类型	期刊论文
条目标识符	http://119.78.100.177/qdio/handle/2XILL650/349829
作者单位	[Pourkhorsandi, Hamed; Debaille, Vinciane; Armytage, Rosalind M. G.; van Ginneken, Matthias] Univ Libre Bruxelles, Lab G Time, CP 160-02,50 Av FD Roosevelt, B-1050 Brussels, Belgium; [Pourkhorsandi, Hamed; Rochette, Pierre; Gattacceca, Jerome] Aix Marseille Univ, CEREGE, INRAE, CNRS,IRD, Aix En Provence, France; [Armytage, Rosalind M. G.] NASA, Jacobs JETS, Johnson Space Ctr, 2101 NASA Pkwy,Mailcode XI3, Houston, TX 77058 USA; [van Ginneken, Matthias] Royal Belgium Inst Nat Sci, Rue Vautier 29, B-1000 Brussels, Belgium
推荐引用方式 GB/T 7714	Pourkhorsandi, Hamed,Debaille, Vinciane,Armytage, Rosalind M. G.,et al. The effects of terrestrial weathering on samarium-neodymium isotopic composition of ordinary chondrites[J]. French National Research Institute for Sustainable Development,2021,562.
APA	Pourkhorsandi, Hamed,Debaille, Vinciane,Armytage, Rosalind M. G.,van Ginneken, Matthias,Rochette, Pierre,&Gattacceca, Jerome.(2021).The effects of terrestrial weathering on samarium-neodymium isotopic composition of ordinary chondrites.CHEMICAL GEOLOGY,562.
MLA	Pourkhorsandi, Hamed,et al."The effects of terrestrial weathering on samarium-neodymium isotopic composition of ordinary chondrites".CHEMICAL GEOLOGY 562(2021).