Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2020 May 8;11(1):2297.
doi: 10.1038/s41467-020-16228-2.

Large mass-independent sulphur isotope anomalies link stratospheric volcanism to the Late Ordovician mass extinction

Dongping Hu  1 , Menghan Li  1 , Xiaolin Zhang  1 , Alexandra V Turchyn  2 , Yizhe Gong  1 , Yanan Shen  3
Affiliations

Large mass-independent sulphur isotope anomalies link stratospheric volcanism to the Late Ordovician mass extinction

Dongping Hu et al. Nat Commun. .

Abstract

Volcanic eruptions are thought to be a key driver of rapid climate perturbations over geological time, such as global cooling, global warming, and changes in ocean chemistry. However, identification of stratospheric volcanic eruptions in the geological record and their causal link to the mass extinction events during the past 540 million years remains challenging. Here we report unexpected, large mass-independent sulphur isotopic compositions of pyrite with Δ33S of up to 0.91‰ in Late Ordovician sedimentary rocks from South China. The magnitude of the Δ33S is similar to that discovered in ice core sulphate originating from stratospheric volcanism. The coincidence between the large Δ33S and the first pulse of the Late Ordovician mass extinction about 445 million years ago suggests that stratospheric volcanic eruptions may have contributed to synergetic environmental deteriorations such as prolonged climatic perturbations and oceanic anoxia, related to the mass extinction.

PubMed Disclaimer

Conflict of interest statement

The authors declare no competing interests.

Figures

Fig. 1
Fig. 1. δ34S and Δ33S data for the Honghuayuan and XY5 sections.
a Honghuayuan section. b XY5 core. K-bentonites are based on ref. . Filled black circles indicate S-isotope mass-independent fractionation (S-MIF), and grey fields denote Δ33S = 0 ± 0.2‰ representing the traditional limit of S-isotope mass-dependent fractionation (S-MDF). Analytical errors are smaller than the symbol sizes for all data reported in this study. N.e.: Normalograptus extraordinarius, A.a.: Akidograptus ascensus, P.a.: Parakidograptus acuminatus, C.v.: Cystograptus vesiculosus, Lung.: Lungmachi, K.: Kuanyinchiao, Hirn.: Hirnantian, HF: Hirnantian Fauna, Rhud.: Rhuddanian, Fm.: Formation, Litho.: Lithology, Bento.: K-bentonites.
Fig. 2
Fig. 2. Summary of Δ33S data over geological time.
Data within the red oval are from this study, and the stratospheric volcanic sulphate data (blue circles) are from refs. ,,,, and the rock record data (grey circles) are compiled from refs. ,,,,,. GOE: Great Oxidation Event.
Fig. 3
Fig. 3. δ34S and δ33S for Honghuayuan and thermochemical sulphate reduction experiments.
Filled black circles represent the S-MIF from Honghuayuan, and blue circles are the experimental data from refs. ,. The dotted line illustrates the fractionation associated with microbial reduction of sulphate with a S-MIF composition (open dotted circle) that fits all pyrites with positive Δ33S anomalies from Honghuayuan. MFL: mass fractionation line, S-MIF: S-isotope mass-independent fractionation, TSR: thermochemical sulphate reduction.
Fig. 4
Fig. 4. Mass-independent S-isotope effects observed in rock and polar record.
The Archean-early Paleoproterozoic rock record (filled grey circles) are compiled from refs. ,,,,,, and the polar record from ice core and snow pits (filled blue circles) are from refs. –,,,. The Late Ordovician rock record (filled red circles) are from this study. The two dotted grey lines illustrate the Archean Reference Array (Δ36S/Δ33S = −0.9 to −1.5) and the Δ36S/Δ33S slopes of photochemistry experiments are compiled from refs. ,, and references therein.
Fig. 5
Fig. 5. Proposed sulphur cycle for the observed isotope record.
UV: ultraviolet, S-MIF: S-isotope mass-independent fractionation, S-MDF: S-isotope mass-dependent fractionation, MSR: microbial sulphate reduction.
Fig. 6
Fig. 6. Cross-plot of total organic carbon and total sulphur.
Filled black circles are from Honghuayuan, and red circles are from XY5. Black solid line represents the typical C/S ratio of ~2.8 for normal marine sediments.
See this image and copyright information in PMC

Similar articles

See all similar articles

Cited by

References

    1. Sheehan PM. The Late Ordovician mass extinction. Annu. Rev. Earth Planet. Sci. 2001;29:331–364. doi: 10.1146/annurev.earth.29.1.331. - DOI
    1. Melchin MJ, Mitchell CE, Holmden C, Storch P. Environmental changes in the Late Ordovician-early Silurian: Review and new insights from black shales and nitrogen isotopes. Geol. Soc. Am. Bull. 2013;125:1635–1670. doi: 10.1130/B30812.1. - DOI
    1. Brenchley PJ, et al. Bathymetric and isotopic evidence for a short-lived Late Ordovician glaciation in a greenhouse period. Geology. 1994;22:295–298. doi: 10.1130/0091-7613(1994)022<0295:BAIEFA>2.3.CO;2. - DOI
    1. Brenchley PJ, et al. High-resolution stable isotope stratigraphy of upper Ordovician sequences: constraints on the timing of bioevents and environmental changes associated with mass extinction and glaciation. Geol. Soc. Am. Bull. 2003;115:89–104. doi: 10.1130/0016-7606(2003)115<0089:HRSISO>2.0.CO;2. - DOI
    1. Saltzman MR, Young SA. Long-lived glaciation in the Late Ordovician? Isotopic and sequence-stratigraphic evidence from western Laurentia. Geology. 2005;33:109–112. doi: 10.1130/G21219.1. - DOI

Publication types