Enhanced marine burial of terrestrial organic carbon through the Palaeocene–Eocene Thermal Maximum
Abstract The Palaeocene–Eocene Thermal Maximum (PETM) occurred ~56 million years ago and was characterized by large-scale carbon release and transient warming. Erosion and subsequent burial of terrestrial organic carbon in marine sediments could have sequestered organic carbon during the PETM—stabilizing global carbon and climate systems—yet direct evidence for this process is lacking. Here we present source-specific biomarker records from five globally distributed shallow marine sites and show that vascular plant and soil organic carbon contributed ~40–95% of total organic carbon in coastal sediments during the PETM. This is higher than modern marine sediments (~12–20% of total organic carbon) and indicates greater terrestrial organic carbon delivery to marine environments during warmer climates. We find that terrestrial organic carbon burial fluxes can increase ~10-to-50-fold during the PETM due to enhanced physical erosion and higher coastal sedimentation rates, implying that marine burial of terrestrial organic carbon sequestered excess carbon released during the PETM. Palaeoclimate model simulations do not account for enhanced delivery of terrestrial organic carbon into the marine realm and are thus missing an important carbon sink. Terrestrial organic carbon burial could act as a negative feedback during other hyperthermals and may aid the long-term (>10,000-year) recovery of the Earth system.
Authors
- Robert Hilton (ORCID: https://orcid.org/0000-0002-0499-3332)
- Richard D. Pancost (ORCID: https://orcid.org/0000-0003-0298-4026)
- Richard Stockey (ORCID: https://orcid.org/0000-0001-5541-7987)
- Thomas Gernon (ORCID: https://orcid.org/0000-0002-7717-2092)
- Marcus P. S. Badger (ORCID: https://orcid.org/0000-0001-8195-5244)
- Alex Farnsworth (ORCID: https://orcid.org/0000-0001-5585-5338)
- Ann Pearson (ORCID: https://orcid.org/0000-0003-2785-8405)
- Jordon Hemingway (ORCID: https://orcid.org/0000-0002-8299-2255)
- Emily H. Hollingsworth (ORCID: https://orcid.org/0000-0002-7067-6837)
- Gordon N. Inglis (ORCID: https://orcid.org/0000-0002-0032-4668)
- Paul J. Valdes (ORCID: https://orcid.org/0000-0002-1902-3283)
- Felix J. Elling (ORCID: https://orcid.org/0000-0003-0405-4033)
- Xiaoxiao Zhao (ORCID: https://orcid.org/0009-0002-3928-5990)
Institutions
- Planetary Science Institute (US)
- Harvard University (US)
- Chinese Academy of Sciences (CN)
- The Open University (GB)
- Christian-Albrechts-Universität zu Kiel (DE)
- University of Bristol (GB)
- University of Oxford (GB)
- Geological Institute (RU)
- Department of Chemistry and Earth Sciences (BY)
- Institute of Tibetan Plateau Research (CN)
- GFZ Helmholtz Centre for Geosciences (DE)
- University of Southampton (GB)
Publication Details
- Journal
- Nature Geoscience
- Published
- 2026-06-16
- DOI
- https://doi.org/10.1038/s41561-026-02012-2
- Primary Topic
- Geology and Paleoclimatology Research
- Type
- article
- Field-Weighted Citation Impact
- 0.00
Funders
- Harvard University
- Royal Society
- University of Southampton
- Deutsche Forschungsgemeinschaft
- Horizon 2020 Framework Programme
- Natural Environment Research Council