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Highly fractionated chromium isotopes in Mesoproterozoic-aged shales and atmospheric oxygen.

ABSTRACT: The history of atmospheric oxygen through the Mesoproterozoic Era is uncertain, but may have played a role in the timing of major evolutionary developments among eukaryotes. Previous work using chromium isotopes in sedimentary rocks has suggested that Mesoproterozoic Era atmospheric oxygen levels were too low in concentration (<0.1% of present-day levels (PAL)) for the expansion of eukaryotic algae and for the evolution of crown-group animals that occurred later in the Neoproterozoic Era. In contrast, our new results on chromium isotopes from Mesoproterozoic-aged sedimentary rocks from the Shennongjia Group from South China is consistent with atmospheric oxygen concentrations of >1% PAL and thus the possibility that a permissive environment existed long before the expansion of various eukaryotic clades.

SUBMITTER: Canfield DE

PROVIDER: S-EPMC6054612 | biostudies-literature | 2018 Jul

REPOSITORIES: biostudies-literature

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Highly fractionated chromium isotopes in Mesoproterozoic-aged shales and atmospheric oxygen.

Canfield Donald E DE Zhang Shuichang S Frank Anja B AB Wang Xiaomei X Wang Huajian H Su Jin J Ye Yuntao Y Frei Robert R

Nature communications 20180720 1

The history of atmospheric oxygen through the Mesoproterozoic Era is uncertain, but may have played a role in the timing of major evolutionary developments among eukaryotes. Previous work using chromium isotopes in sedimentary rocks has suggested that Mesoproterozoic Era atmospheric oxygen levels were too low in concentration (<0.1% of present-day levels (PAL)) for the expansion of eukaryotic algae and for the evolution of crown-group animals that occurred later in the Neoproterozoic Era. In co ...[more]

PMID: 30030422

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Dataset Information

Highly fractionated chromium isotopes in Mesoproterozoic-aged shales and atmospheric oxygen.

Publications

Highly fractionated chromium isotopes in Mesoproterozoic-aged shales and atmospheric oxygen.

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