The DOI matches its Crossref record; 10 of the 10 references it cites were found in a registry or an index.
A major perturbation of the carbon cycle before the Ghaub glaciation (Neoproterozoic) in Namibia: Prelude to snowball Earth?
Open accessAbstract
A large (11–15‰) negative shift in δ 13 C is observed in shallow water carbonates directly beneath Neoproterozoic glacial deposits (or correlative disconformity) in northwest Namibia ascribed to a snowball Earth. Reproducibility and stratigraphic concordance of this anomaly in 16 sections across the ancient continental shelf support a primary origin, and field relations show it predates the fall in sea level associated with the Ghaub glaciation. We crudely estimate the duration of the isotopic shift as ∼0.6 × 10 6 years from a simple thermal subsidence model. Similar or larger δ 13 C anomalies are found directly beneath Neoproterozoic glacial units in Australia, Canada, China, Scotland, and Svalbard. After considering conventional interpretations for negative δ 13 C anomalies, we conclude that a prolonged methane release to the atmosphere is most consistent with the timescale, magnitude, and geological context of the anomaly in Namibia. Counterintuitively, an anomalous methane flux that is sustained for 100s kyr may be consistent with a snowball glaciation.
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Cites
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A Neoproterozoic Snowball Earth
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Self-citationThe Global Carbon Cycle: A Test of Our Knowledge of Earth as a System
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The Chemical Evolution of the Atmosphere and Oceans
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The snowball Earth hypothesis: testing the limits of global change
Hoffman, P. F., & Schrag, D. P. (2002) · Terra Nova · doi:10.1046/j.1365-3121.2002.00408.x · Cited by 1,585
Self-citationInterpreting carbon-isotope excursions: carbonates and organic matter
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“A reduction in forg to near 0 would cause the d13C of the whole ocean to evolve toward d13Cinput, assumed to be approximately 5% for the Neoproterozoic [Hayes et al., 1999].”
BackgroundSelf-citationGreenhouse warming by CH 4 in the atmosphere of early Earth
Pavlov, A. A., Kasting, J. F., Brown, L. L., Rages, K. A., & Freedman, R. (2000) · Journal of Geophysical Research: Planets · doi:10.1029/1999je001134 · Cited by 537
Isotopes, ice ages, and terminal Proterozoic earth history
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Cited by
The snowball Earth hypothesis: testing the limits of global change
Hoffman, P. F., & Schrag, D. P. (2002) · Terra Nova · doi:10.1046/j.1365-3121.2002.00408.x · Cited by 1,585
Self-citationFossil steroids record the appearance of Demospongiae during the Cryogenian period
Love, G. D., Grosjean, E., Stalvies, C., Fike, D. A., Grotzinger, J. P., Bradley, A. S., Kelly, A. E., Bhatia, M., Meredith, W., Snape, C. E., et al. (2009) · Nature · doi:10.1038/nature07673 · Cited by 731
Dynamics of the Neoproterozoic carbon cycle
Rothman, D. H., Hayes, J. M., & Summons, R. E. (2003) · Proceedings of the National Academy of Sciences · doi:10.1073/pnas.0832439100 · Cited by 608
Neoproterozoic chemostratigraphy
Halverson, G. P., Wade, B. P., Hurtgen, M. T., & Barovich, K. M. (2010) · Precambrian Research · doi:10.1016/j.precamres.2010.04.007 · Cited by 400
Self-citationUncovering the Neoproterozoic carbon cycle
Johnston, D. T., Macdonald, F. A., Gill, B. C., Hoffman, P. F., & Schrag, D. P. (2012) · Nature · doi:10.1038/nature10854 · Cited by 208
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Metadata
- Authors
- Halverson, G. P., Hoffman, P. F., Schrag, D. P., & Kaufman, A. J.
- Venue
- Geochemistry, Geophysics, Geosystems
- Publisher
- American Geophysical Union (AGU)
- Published
- 2002-06
- Volume
- 3
- Issue
- 6
- Pages
- 1-24
- ISSN
- 1525-2027 (ISSN-L)
- OpenAlex
- W1513468313
- Cited by
- 164
- References
- 10
- FWCI
- 8.17
- Type
- journal article
- Language
- en
- Open access
- bronze
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