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DOI	10.1111/gbi.12385
	In Situ Fe and S isotope analyses in pyrite from the 3.2 Ga Mendon Formation (Barberton Greenstone Belt, South Africa): Evidence for early microbial iron reduction
	Marin-Carbonne J.; Busigny V.; Miot J.; Rollion-Bard C.; Muller E.; Drabon N.; Jacob D.; Pont S.; Robyr M.; Bontognali T.R.R.; François C.; Reynaud S.; Van Zuilen M.; Philippot P.
发表日期	2020
ISSN	14724677
起始页码	306
结束页码	325
卷号	18 期号:3
英文摘要	On the basis of phylogenetic studies and laboratory cultures, it has been proposed that the ability of microbes to metabolize iron has emerged prior to the Archaea/Bacteria split. However, no unambiguous geochemical data supporting this claim have been put forward in rocks older than 2.7–2.5 giga years (Gyr). In the present work, we report in situ Fe and S isotope composition of pyrite from 3.28- to 3.26-Gyr-old cherts from the upper Mendon Formation, South Africa. We identified three populations of microscopic pyrites showing a wide range of Fe isotope compositions, which cluster around two δ56Fe values of −1.8‰ and +1‰. These three pyrite groups can also be distinguished based on the pyrite crystallinity and the S isotope mass-independent signatures. One pyrite group displays poorly crystallized pyrite minerals with positive Δ33S values > +3‰, while the other groups display more variable and closer to 0‰ Δ33S values with recrystallized pyrite rims. It is worth to note that all the pyrite groups display positive Δ33S values in the pyrite core and similar trace element compositions. We therefore suggest that two of the pyrite groups have experienced late fluid circulations that have led to partial recrystallization and dilution of S isotope mass-independent signature but not modification of the Fe isotope record. Considering the mineralogy and geochemistry of the pyrites and associated organic material, we conclude that this iron isotope systematic derives from microbial respiration of iron oxides during early diagenesis. Our data extend the geological record of dissimilatory iron reduction (DIR) back more than 560 million years (Myr) and confirm that micro-organisms closely related to the last common ancestor had the ability to reduce Fe(III). © 2020 The Authors. Geobiology published by John Wiley & Sons Ltd.
关键词	bacterium biogeochemical cycle biogeochemistry common ancestry geochemistry geological record microbial activity microbial community mineralogy phylogenetics pyrite stable isotope trace element Barberton Greenstone Belt South Africa
语种	英语
来源机构	Geobiology
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/133186
推荐引用方式 GB/T 7714	Marin-Carbonne J.,Busigny V.,Miot J.,et al. In Situ Fe and S isotope analyses in pyrite from the 3.2 Ga Mendon Formation (Barberton Greenstone Belt, South Africa): Evidence for early microbial iron reduction[J]. Geobiology,2020,18(3).
APA	Marin-Carbonne J..,Busigny V..,Miot J..,Rollion-Bard C..,Muller E..,...&Philippot P..(2020).In Situ Fe and S isotope analyses in pyrite from the 3.2 Ga Mendon Formation (Barberton Greenstone Belt, South Africa): Evidence for early microbial iron reduction.,18(3).
MLA	Marin-Carbonne J.,et al."In Situ Fe and S isotope analyses in pyrite from the 3.2 Ga Mendon Formation (Barberton Greenstone Belt, South Africa): Evidence for early microbial iron reduction".18.3(2020).