Iron isotope biosignatures

被引：333

作者：

Beard, BL

Johnson, CM

Cox, L

Sun, H

Nealson, KH

Aguilar, C

机构：

[1] Univ Wisconsin, Dept Geol & Geophys, Madison, WI 53706 USA

[2] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA

[3] Univ Wisconsin, Inst Great Lakes Study, Milwaukee, WI 53204 USA

来源：

SCIENCE | 1999年 / 285卷 / 5435期

关键词：

D O I：

10.1126/science.285.5435.1889

中图分类号：

O [数理科学和化学]; P [天文学、地球科学]; Q [生物科学]; N [自然科学总论];

学科分类号：

07 ; 0710 ; 09 ;

摘要：

The Fe-56/Fe-54 of Fe-bearing phases precipitated in sedimentary environments varies by 2.5 per mil (delta(56)Fe values of +0.9 to -1.6 per mil). In contrast, the Fe-56/Fe-54 of Fe-bearing phases in igneous rocks from Earth and the moon does not vary measurably (delta(56)Fe = 0.0 +/- 0.3 per mil). Experiments with dissimilatory Fe-reducing bacteria of the genus Shewanella algae grown on a ferrihydrite substrate indicate that the delta(56)Fe of ferrous Fe in solution is isotopically Lighter than the ferrihydrite substrate by 1.3 per mil. Therefore, the range in delta(56)Fe values of sedimentary rocks may reflect biogenic fractionation, and the isotopic composition of Fe may be used to trace the distribution of microorganisms in modern and ancient Earth.

引用

页码：1889 / 1892

页数：4

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BEARD BL, IN PRESS GEOCHIM COS

[2]

Bullen T.D., 1998, MINERAL MAG A, V62, P255

[3]

BULLEN TD, 1997, EOS, V78, pS173

[4]

CALDEIRA K, 1990, EXTINCTION EVENTS EA, P333, DOI DOI 10.1007/BFB0011156