Oxygen-isotope evidence from ancient zircons for liquid water at the Earth's surface 4,300 Myr ago
Abstract
Granitoid gneisses and supracrustal rocks that are 3,800-4,000 Myr old are the oldest recognized exposures of continental crust. To obtain insight into conditions at the Earth's surface more than 4 Gyr ago requires the analysis of yet older rocks or their mineral remnants. Such an opportunity is presented by detrital zircons more than 4 Gyr old found within 3-Gyr-old quartzitic rocks in the Murchison District of Western Australia. Here we report in situ U-Pb and oxygen isotope results for such zircons that place constraints on the age and composition of their sources and may therefore provide information about the nature of the Earth's early surface. We find that 3,910-4,280 Myr old zircons have oxygen isotope (delta18O) values ranging from 5.4+/-0.6% to 15.0+/-0.4%. On the basis of these results, we postulate that the approximately 4,300-Myr-old zircons formed from magmas containing a significant component of re-worked continental crust that formed in the presence of water near the Earth's surface. These data are therefore consistent with the presence of a hydrosphere interacting with the crust by 4,300 Myr ago.
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Elevated 18O/16O in 4.3-Ga-old zircons was possibly inherited from 18O-enriched, weathered surface rocks that were later buried and melted, which implies the presence of surficial liquid water and even land.
“Elevated 18O/16O in 4.3-Ga-old zircons was possibly inherited from 18O-enriched, weathered surface rocks that were later buried and melted, which implies the presence of surficial liquid water and even land (17, 18).”
From The Archean atmosphere (2020) · cites this paper as [17]
The ribosome may have first originated in a peptide/RNA world, where both amino acids and a variety of enzymes were available.
“In recent times, the role of proteins in the origin of ribosomes is gaining currency, implying that the ribosome may have first originated in a peptide/RNA world, where both amino acids and a variety of enzymes were available [9,13,14,15,16,17,18,19,20,21,22,92].”
From The Origin of Prebiotic Information System in the Peptide/RNA World: A Simulation Model of the Evolution of Translation and the Genetic Code (2019) · cites this paper as [15]
Liquid water was already present at the Earth's surface during the Hadean and Archean eons.
“liquid water was already present at the surface during the Hadean (4.56 Ga to ≈ 4.0 Ga 1 ) and Archean eons ( ≈ 4.0 Ga to 2.4 Ga)”
From The young Sun's XUV-activity as a constraint for lower CO2-limits in the Earth's Archean atmosphere (2021) · cites this paper as Mojzsis et al., 2001
Evidence for liquid water dates back to 4.3 Ga.
“Evidence for liquid water dates back to 4.3 Ga (Mojzsis et al., 2001).”
From The Astrobiology Primer v2.0 (2016) · cites this paper as Mojzsis et al., 2001
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- Authors
- Mojzsis, S. J., Harrison, T. M., & Pidgeon, R. T.
- Affiliations
- University of California, Los Angeles (US)
- Curtin University (AU)
- Corresponding author
- Mojzsis, Stephen J.
- Venue
- Nature
- Published
- 2001-01
- Volume
- 409
- Issue
- 6817
- Pages
- 178-181
- ISSN
- 0028-0836 (ISSN-L)
- 1476-4687
- OpenAlex
- W1988503846
- Cited by
- 863
- References
- 31
- Citations by year
- 2026: 24 · 2025: 42 · 2024: 38 · 2023: 38 · 2022: 27 · 2021: 34 · 2020: 42 · 2019: 34 · 2018: 68 · 2017: 39 · 2016: 36 · 2015: 35 · 2014: 30 · 2013: 41 · 2012: 20
- FWCI
- 31.21
- Type
- journal article
- Language
- en
- Open access
- closed
- Licence
- www.springer.com/tdm (tdm)
- Locations
- Nature (publishedVersion)
- PubMed (publishedVersion)
- RePEc: Research Papers in Economics (submittedVersion)
- Funders
- National Science Foundation
- U.S. Department of Energy
- National Aeronautics and Space Administration
- Natural Environment Research Council
- Australian Research Council
- Topics
- Physical Sciences › Earth and Planetary Sciences › Geophysics › Geological and Geochemical Analysis
- Physical Sciences › Physics and Astronomy › Astronomy and Astrophysics › Astro and Planetary Science
- Physical Sciences › Earth and Planetary Sciences › Geochemistry and Petrology › Geochemistry and Elemental Analysis
- Keywords
- detrital zircon, oxygen isotopes, U-Pb geochronology, granitic gneiss, crustal recycling
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