Skip to main content

Thank you for visiting nature.com. You are using a browser version with limited support for CSS. To obtain the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in Internet Explorer). In the meantime, to ensure continued support, we are displaying the site without styles and JavaScript.

Methane hydrate dissociation across the Oligocene–Miocene boundary

Abstract

Methane hydrate dissociation has long been considered as a mechanism for global carbon cycle perturbations, climate change and even mass extinctions in Earth’s history. However, direct evidence of hydrate destabilization and methane release coinciding with such events is scarce. Here we report the presence of diagnostic lipid biomarkers with depleted carbon isotopes from three sites in the Southern Ocean that are directly linked to methane release and subsequent oxidation across the Oligocene–Miocene boundary (23 million years ago). The biomarker evidence indicates that the hydrate destabilization was initiated during the peak of the Oligocene–Miocene boundary glaciation and sea-level low stand, consistent with our model results suggesting the decrease in hydrostatic pressure eroded the base of global methane hydrate stability zones. Aerobic oxidation of methane in seawater consumes oxygen and acidifies the ocean, acting as a negative feedback that perhaps facilitated the rapid and mysterious termination of glaciation in the early Miocene.

This is a preview of subscription content, access via your institution

Access options

Buy article

Get time limited or full article access on ReadCube.

$32.00

All prices are NET prices.

Fig. 1: Location of our studied sites.
Fig. 2: Coupling between late Oligocene–early Miocene global climate/sea-level and gas hydrate dissociation in the Southern Ocean.
Fig. 3: Schematic of changes of the GHSZ during interglacial and Mi-1 (peak glacial) conditions.
Fig. 4: GHSZ variations in the sediment column in response to a eustatic sea-level drop of 50 m.

Data availability

All lipid biomarker and compound-specific carbon isotope data used in this study are available for download from the NOAA National Centers for Environmental Information website (https://www.ncei.noaa.gov/access/paleo-search/study/35113) and are also archived as a Supplementary Data file with the online version of this Article.

References

  1. Ruppel, C. D. & Kessler, J. D. The interaction of climate change and methane hydrates. Rev. Geophys. 55, 126–168 (2017).

    Article  Google Scholar 

  2. Hester, K. C. & Brewer, P. G. Clathrate hydrates in nature. Ann. Rev. Mar. Sci. 1, 303–327 (2009).

    Article  Google Scholar 

  3. Jiang, G., Kennedy, M. J. & Christie-Blick, N. Stable isotopic evidence for methane seeps in Neoproterozoic postglacial cap carbonates. Nature 426, 822–826 (2003).

    Article  Google Scholar 

  4. Berner, R. A. Examination of hypotheses for the Permo-Triassic boundary extinction by carbon cycle modeling. Proc. Natl Acad. Sci. USA 99, 4172–4177 (2002).

    Article  Google Scholar 

  5. Dickens, G. R., O’Neil, J. R., Rea, D. K. & Owen, R. M. Dissociation of oceanic methane hydrate as a cause of the carbon isotope excursion at the end of the Paleocene. Paleoceanography 10, 965–971 (1995).

    Article  Google Scholar 

  6. Bristow, T. F., Bonifacie, M., Derkowski, A., Eiler, J. M. & Grotzinger, J. P. A hydrothermal origin for isotopically anomalous cap dolostone cements from south China. Nature 474, 68–71 (2011).

    Article  Google Scholar 

  7. Stott, L. D. et al. Does the oxidation of methane leave an isotopic fingerprint in the geologic record? Geochem. Geophys. Geosyst. 3, 2001GC000196 (2002).

    Article  Google Scholar 

  8. Boetius, A. et al. A marine microbial consortium apparently mediating anaerobic oxidation of methane. Nature 407, 623–626 (2000).

    Article  Google Scholar 

  9. Hinrichs, K.-U., Hayes, J. M., Sylva, S. P., Brewer, P. G. & DeLong, E. F. Methane-consuming archaebacteria in marine sediments. Nature 398, 802–805 (1999).

    Article  Google Scholar 

  10. Valentine, D. L., Blanton, D. C., Reeburgh, W. S. & Kastner, M. Water column methane oxidation adjacent to an area of active hydrate dissociation, Eel River Basin. Geochim. Cosmochim. Acta 65, 2633–2640 (2001).

    Article  Google Scholar 

  11. Niemann, H. & Elvert, M. Diagnostic lipid biomarker and stable carbon isotope signatures of microbial communities mediating the anaerobic oxidation of methane with sulphate. Org. Geochem. 39, 1668–1677 (2008).

    Article  Google Scholar 

  12. Blumenberg, M., Seifert, R., Reitner, J., Pape, T. & Michaelis, W. Membrane lipid patterns typify distinct anaerobic methanotrophic consortia. Proc. Natl Acad. Sci. USA 101, 11111–11116 (2004).

    Article  Google Scholar 

  13. Peckmann, J. & Thiel, V. Carbon cycling at ancient methane-seeps. Chem. Geol. 205, 443–467 (2004).

    Article  Google Scholar 

  14. Hinrichs, K. U. A molecular recorder of methane hydrate destabilization. Geochem. Geophys. Geosyst. 2, 2000GC000118 (2001).

    Article  Google Scholar 

  15. Hinrichs, K.-U., Hmelo, L. R. & Sylva, S. P. Molecular fossil record of elevated methane levels in late Pleistocene coastal waters. Science 299, 1214–1217 (2003).

    Article  Google Scholar 

  16. Zhang, Y. G. et al. Methane index: a tetraether archaeal lipid biomarker indicator for detecting the instability of marine gas hydrates. Earth Planet. Sci. Lett. 307, 525–534 (2011).

    Article  Google Scholar 

  17. Schouten, S., Hopmans, E. C., Schefuß, E. & Damste, J. S. S. Distributional variations in marine crenarchaeotal membrane lipids: a new tool for reconstructing ancient sea water temperatures? Earth Planet. Sci. Lett. 204, 265–274 (2002).

    Article  Google Scholar 

  18. Zachos, J. C., Pagani, M., Sloan, L., Thomas, E. & Billups, K. Trends, rhythms and aberrations in global climate 65 Ma to present. Science 292, 686–693 (2001).

    Article  Google Scholar 

  19. Beddow, H. M., Liebrand, D., Sluijs, A., Wade, B. S. & Lourens, L. J. Global change across the Oligocene-Miocene transition: high‐resolution stable isotope records from IODP site U1334 (equatorial Pacific Ocean). Paleoceanography 31, 81–97 (2016).

    Article  Google Scholar 

  20. Mudelsee, M., Bickert, T., Lear, C. H. & Lohmann, G. Cenozoic climate changes: a review based on time series analysis of marine benthic δ18O records. Rev. Geophys. 52, 333–374 (2014).

    Article  Google Scholar 

  21. Naish, T. R. et al. Orbitally induced oscillations in the East Antarctic ice sheet at the Oligocene/Miocene boundary. Nature 413, 719–723 (2001).

    Article  Google Scholar 

  22. Liebrand, D. et al. Evolution of the early Antarctic ice ages. Proc. Natl Acad. Sci. USA 114, 3867–3872 (2017).

    Article  Google Scholar 

  23. Zachos, J. C., Shackleton, N. J., Revenaugh, J. S., Pälike, H. & Flower, B. P. Climate response to orbital forcing across the Oligocene–Miocene boundary. Science 292, 274–278 (2001).

    Article  Google Scholar 

  24. Greenop, R. et al. Orbital forcing, ice volume, and CO2 across the Oligocene‐Miocene transition. Paleoceanogr. Paleoclimatol. 34, 316–328 (2019).

    Article  Google Scholar 

  25. Hartman, J. D., Sangiorgi, F. & Escutia, C. Paleoceanography and ice sheet variability offshore Wilkes Land, Antarctica—Part 3: insights from Oligocene-Miocene TEX86-based sea surface temperature reconstructions. Clim. Past 14, 1275–1297 (2018).

    Article  Google Scholar 

  26. Pfuhl, H. A., Mccave, I. N., Schellenberg, S. A. & Ferretti, P. Changes in Southern Ocean circulation in late Oligocene to early Miocene time. Geophys. Monogr. 151, 173–189 (2004).

    Google Scholar 

  27. Thiel, V. et al. Highly isotopically depleted isoprenoids: molecular markers for ancient methane venting. Geochim. Cosmochim. Acta 63, 3959–3966 (1999).

    Article  Google Scholar 

  28. Egger, M., Riedinger, N., Mogollón, J. M. & Jørgensen, B. B. Global diffusive fluxes of methane in marine sediments. Nat. Geosci. 11, 421–425 (2018).

    Article  Google Scholar 

  29. Buffett, B. & Archer, D. Global inventory of methane clathrate: sensitivity to changes in the deep ocean. Earth Planet. Sci. Lett. 227, 185–199 (2004).

    Article  Google Scholar 

  30. Miller, K. G. et al. Cenozoic sea-level and cryospheric evolution from deep-sea geochemical and continental margin records. Sci. Adv. 6, eaaz1346 (2020).

    Article  Google Scholar 

  31. Cook, M. S., Keigwin, L. D., Birgel, D. & Hinrichs, K. U. Repeated pulses of vertical methane flux recorded in glacial sediments from the southeast Bering Sea. Paleoceanography 26, PA2210 (2011).

    Article  Google Scholar 

  32. Paull, C. K., Ussler, W. & Dillon, W. P. Is the extent of glaciation limited by marine gas‐hydrates? Geophys. Res. Lett. 18, 432–434 (1991).

    Article  Google Scholar 

  33. Maslin, M., Mikkelsen, N., Vilela, C. & Haq, B. Sea-level- and gas-hydrate-controlled catastrophic sediment failures of the Amazon Fan. Geology 26, 1107–1110 (1998).

    Article  Google Scholar 

  34. Straume, E. O., Gaina, C., Medvedev, S. & Nisancioglu, K. H. Global Cenozoic paleobathymetry with a focus on the Northern Hemisphere Oceanic Gateways. Gondwana Res. 86, 126–143 (2020).

    Article  Google Scholar 

  35. Wallmann, K. et al. Gas hydrate dissociation off Svalbard induced by isostatic rebound rather than global warming. Nat. Commun. 9, 83 (2018).

    Article  Google Scholar 

  36. Mitrovica, J. X., Tamisiea, M. E., Davis, J. L. & Milne, G. A. Recent mass balance of polar ice sheets inferred from patterns of global sea-level change. Nature 409, 1026–1029 (2001).

    Article  Google Scholar 

  37. McGinnis, D. F., Greinert, J., Artemov, Y., Beaubien, S. & Wüest, A. Fate of rising methane bubbles in stratified waters: how much methane reaches the atmosphere?. J. Geophys. Res. Oceans 111, C09007 (2006).

    Article  Google Scholar 

  38. Dickens, G. On the fate of past gas: what happens to methane released from a bacterially mediated gas hydrate capacitor? Geochem. Geophys. Geosyst. 2, 2000GC000131 (2001).

    Article  Google Scholar 

  39. Kessler, J. D. et al. A persistent oxygen anomaly reveals the fate of spilled methane in the deep Gulf of Mexico. Science 331, 312–315 (2011).

    Article  Google Scholar 

  40. Boetius, A. & Wenzhöfer, F. Seafloor oxygen consumption fuelled by methane from cold seeps. Nat. Geosci. 6, 725–734 (2013).

    Article  Google Scholar 

  41. Mawbey, E. M. & Lear, C. H. Carbon cycle feedbacks during the Oligocene-Miocene transient glaciation. Geology 41, 963–966 (2013).

    Article  Google Scholar 

  42. Kennett, J. P., Cannariato, K. G., Hendy, I. L. & Behl, R. J. Methane Hydrates in Quaternary Climate Change: The Clathrate Gun Hypothesis (Wiley, 2003).

  43. Kvenvolden, K. A. Potential effects of gas hydrate on human welfare. Proc. Natl Acad. Sci. USA 96, 3420–3426 (1999).

    Article  Google Scholar 

  44. Archer, D. Methane hydrate stability and anthropogenic climate change. Biogeosciences 4, 521–544 (2007).

    Article  Google Scholar 

  45. Oppo, D., De Siena, L. & Kemp, D. A record of seafloor methane seepage across the last 150 million years. Sci. Rep. 10, 2562 (2020).

    Article  Google Scholar 

  46. 2-Minute Gridded Global Relief Data (ETOPO2) v2 (National Oceanic and Atmospheric Administration, National Geophysical Data Center, 2006); https://www.ncei.noaa.gov/access/metadata/landing-page/bin/iso?id=gov.noaa.ngdc.mgg.dem:301

  47. Exon, N. F. et al. (eds) Site 1168. In Proc. Ocean Drilling Program, Initial Reports, 189 1–170 (Shipboard Scientific Party, 2001); https://doi.org/10.2973/odp.proc.ir.189.103.2001

  48. Exon, N. F. et al. (eds) Site 1170. In Proc. Ocean Drilling Program, Initial Reports, 189 1–167 (Shipboard Scientific Party, 2001); https://doi.org/10.2973/odp.proc.ir.189.105.2001

  49. Expedition 318 Scientists. Site U1356. In Proc. IODP (eds Escutia, C. et al.) 318 (Integrated Ocean Drilling Program Management International, 2011).

  50. Müller, R. D. et al. GPlates: building a virtual Earth through deep time. Geochem. Geophys. Geosyst. 19, 2243–2261 (2018).

    Article  Google Scholar 

  51. Seton, M. et al. Global continental and ocean basin reconstructions since 200 Ma. Earth Sci. Rev. 113, 212–270 (2012).

    Article  Google Scholar 

  52. Pfuhl, H. A. & McCave, I. N. Integrated age models for the early Oligocene-early Miocene, sites 1168 and 1170–1172. Proc. ODP Sci. Results 189, 1–21 (2003).

    Google Scholar 

  53. Gradstein, F. M., Ogg, J. G., Schmitz, M. & Ogg, G. The Geologic Time Scale 2012 (Elsevier, 2012).

  54. Bijl, P. K., Houben, A. J., Bruls, A., Pross, J. & Sangiorgi, F. Stratigraphic calibration of Oligocene-Miocene organic-walled dinoflagellate cysts from offshore Wilkes Land, East Antarctica, and a zonation proposal. J. Micropalaeontol. 37, 105–138 (2018).

    Article  Google Scholar 

  55. Tauxe, L. et al. Chronostratigraphic framework for the IODP Expedition 318 cores from the Wilkes Land Margin: constraints for paleoceanographic reconstruction. Paleoceanography 27, PA2214 (2012).

    Article  Google Scholar 

  56. Passchier, S., Ciarletta, D. J., Henao, V. & Sekkas, V. Sedimentary processes and facies on a high-latitude passive continental margin, Wilkes Land, East Antarctica. Geol. Soc. Spec. Publ. 475, 181–201 (2019).

    Article  Google Scholar 

  57. Lyle, M., Gibbs, S., Moore, T. C. & Rea, D. K. Late Oligocene initiation of the Antarctic circumpolar current: evidence from the South Pacific. Geology 35, 691–694 (2007).

    Article  Google Scholar 

  58. Becker, K. W., Lipp, J. S., Versteegh, G. J., Wörmer, L. & Hinrichs, K.-U. Rapid and simultaneous analysis of three molecular sea surface temperature proxies and application to sediments from the Sea of Marmara. Org. Geochem. 85, 42–53 (2015).

    Article  Google Scholar 

  59. Pancost, R., Hopmans, E. & Damsté, J. S. Archaeal lipids in Mediterranean cold seeps: molecular proxies for anaerobic methane oxidation. Geochim. Cosmochim. Acta 65, 1611–1627 (2001).

    Article  Google Scholar 

  60. Tierney, J. E. & Tingley, M. P. A TEX86 surface sediment database and extended Bayesian calibration. Sci. Data 2, 150029 (2015).

    Article  Google Scholar 

  61. Bian, L. et al. Algal and archaeal polyisoprenoids in a recent marine sediment: molecular isotopic evidence for anaerobic oxidation of methane. Geochem. Geophys. Geosyst. 2, 2000GC000112 (2001).

    Article  Google Scholar 

  62. Knittel, K. & Boetius, A. Anaerobic oxidation of methane: progress with an unknown process. Ann. Rev. Microbiol. 63, 311–334 (2009).

    Article  Google Scholar 

  63. Elvert, M., Hopmans, E. C., Treude, T., Boetius, A. & Suess, E. Spatial variations of methanotrophic consortia at cold methane seeps: implications from a high‐resolution molecular and isotopic approach. Geobiology 3, 195–209 (2005).

    Article  Google Scholar 

  64. Joye, S. B. et al. The anaerobic oxidation of methane and sulfate reduction in sediments from Gulf of Mexico cold seeps. Chem. Geol. 205, 219–238 (2004).

    Article  Google Scholar 

  65. Lengger, S. K., Hopmans, E. C., Sinninghe Damsté, J. S. & Schouten, S. Fossilization and degradation of archaeal intact polar tetraether lipids in deeply buried marine sediments (Peru Margin). Geobiology 12, 212–220 (2014).

    Article  Google Scholar 

  66. Pi, Y. et al. Archaeal lipids and 16S rRNA genes characterizing non-hydrate and hydrate-impacted sediments in the Gulf of Mexico. Geomicrobiol. J. 26, 227–237 (2009).

    Article  Google Scholar 

  67. Gontharet, S., Stadnitskaia, A., Bouloubassi, I., Pierre, C. & Damsté, J. S. Palaeo methane-seepage history traced by biomarker patterns in a carbonate crust Nile deep-sea fan (eastern Mediterranean Sea). Mar. Geol. 261, 105–113 (2009).

    Article  Google Scholar 

  68. Werne, J. P. & Damsté, J. S. Mixed sources contribute to the molecular isotopic signature of methane-rich mud breccia sediments of Kazan mud volcano (eastern Mediterranean). Org. Geochem. 36, 13–27 (2005).

    Article  Google Scholar 

  69. Weijers, J. W., Lim, K. L., Aquilina, A., Sinninghe Damsté, J. S. & Pancost, R. D. Biogeochemical controls on glycerol dialkyl glycerol tetraether lipid distributions in sediments characterized by diffusive methane flux. Geochem. Geophys. Geosyst. 12, Q10010 (2011).

    Article  Google Scholar 

  70. Chevalier, N., Bouloubassi, I., Stadnitskaia, A., Taphanel, M.-H. & Damsté, J. S. S. Lipid biomarkers for anaerobic oxidation of methane and sulphate reduction in cold seep sediments of Nyegga pockmarks (Norwegian margin): discrepancies in contents and carbon isotope signatures. Geo-Mar. Lett. 34, 269–280 (2014).

    Article  Google Scholar 

  71. Lee, D.-H. et al. Discriminative biogeochemical signatures of methanotrophs in different chemosynthetic habitats at an active mud volcano in the Canadian Beaufort Sea. Sci. Rep. 9, 17592 (2019).

    Article  Google Scholar 

  72. Park, Y.-H., Yamamoto, M., Polyak, L. & Nam, S.-I. Glycerol dialkyl glycerol tetraether variations in the northern Chukchi Sea, Arctic Ocean, during the Holocene. Preprint at Biogeosci. Discuss. https://doi.org/10.5194/bg-2016-529 (2016).

  73. Paull, C. K., Buelow, W. J., Ussler, W. III & Borowski, W. S. Increased continental-margin slumping frequency during sea-level lowstands above gas hydrate-bearing sediments. Geology 24, 143–146 (1996).

    Article  Google Scholar 

  74. Katz, M. E., Pak, D. K., Dickens, G. R. & Miller, K. G. The source and fate of massive carbon input during the latest Paleocene thermal maximum. Science 286, 1531–1533 (1999).

    Article  Google Scholar 

  75. Andreassen, K. et al. Massive blow-out craters formed by hydrate-controlled methane expulsion from the Arctic seafloor. Science 356, 948–953 (2017).

    Article  Google Scholar 

  76. Vogt, P. R., Crane, K., Sundvor, E., Max, M. D. & Pfirman, S. L. Methane-generated (?) pockmarks on young, thickly sedimented oceanic crust in the Arctic: Vestnesa Ridge, Fram Strait. Geology 22, 255–258 (1994).

    Article  Google Scholar 

  77. Bayon, G. et al. U-Th isotope constraints on gas hydrate and pockmark dynamics at the Niger Delta margin. Mar. Geol. 370, 87–98 (2015).

    Article  Google Scholar 

  78. Rothwell, R., Thomson, J. & Kähler, G. Low-sea-level emplacement of a very large late Pleistocene ‘megaturbidite’ in the western Mediterranean Sea. Nature 392, 377–380 (1998).

    Article  Google Scholar 

  79. Kayen, R. E. & Lee, H. J. Pleistocene slope instability of gas hydrate‐laden sediment on the Beaufort Sea margin. Mar. Georesources Geotechnol. 10, 125–141 (1991).

    Article  Google Scholar 

  80. Kennett, J. P. & Fackler-Adams, B. N. Relationship of clathrate instability to sediment deformation in the upper Neogene of California. Geology 28, 215–218 (2000).

    Article  Google Scholar 

  81. Salabarnada, A. et al. Paleoceanography and ice sheet variability offshore Wilkes Land, Antarctica—Part 1: insights from late Oligocene astronomically paced contourite sedimentation. Clim. Past 14, 991–1014 (2018).

    Article  Google Scholar 

  82. Passaro, S. et al. Seafloor doming driven by degassing processes unveils sprouting volcanism in coastal areas. Sci. Rep. 6, 22448 (2016).

    Article  Google Scholar 

  83. Bryn, P., Berg, K., Forsberg, C. F., Solheim, A. & Kvalstad, T. J. Explaining the Storegga slide. Mar. Pet. Geol. 22, 11–19 (2005).

    Article  Google Scholar 

  84. Lear, C. H., Rosenthal, Y., Coxall, H. K. & Wilson, P. Late Eocene to early Miocene ice sheet dynamics and the global carbon cycle. Paleoceanography 261, 534–550 (2004).

    Google Scholar 

  85. Liu, Z. et al. Transient temperature asymmetry between hemispheres in the Palaeogene Atlantic Ocean. Nat. Geosci. 11, 656–660 (2018).

    Article  Google Scholar 

  86. O’Brien, C. L. et al. The enigma of Oligocene climate and global surface temperature evolution. Proc. Natl Acad. Sci. USA 117, 25302–25309 (2020).

    Article  Google Scholar 

  87. Locarnini, M. et al. World Ocean Atlas 2018, Volume 1: Temperature (US Department of Commerce, 2018).

  88. Archer, D., Buffett, B. & Brovkin, V. Ocean methane hydrates as a slow tipping point in the global carbon cycle. Proc. Natl Acad. Sci. USA 106, 20596–20601 (2009).

    Article  Google Scholar 

  89. Tishchenko, P., Hensen, C., Wallmann, K. & Wong, C. S. Calculation of the stability and solubility of methane hydrate in seawater. Chem. Geol. 219, 37–52 (2005).

    Article  Google Scholar 

  90. Dickens, G. R. The potential volume of oceanic methane hydrates with variable external conditions. Org. Geochem. 32, 1179–1193 (2001).

    Article  Google Scholar 

  91. Milkov, A. V. Global estimates of hydrate-bound gas in marine sediments: how much is really out there? Earth Sci. Rev. 66, 183–197 (2004).

    Article  Google Scholar 

  92. Boswell, R. & Collett, T. S. Current perspectives on gas hydrate resources. Energy Environ. Sci. 4, 1206–1215 (2011).

    Article  Google Scholar 

  93. Reeburgh, W. S. Oceanic methane biogeochemistry. Chem. Rev. 107, 486–513 (2007).

    Article  Google Scholar 

  94. Zeebe, R. E. & Wolf-Gladrow, D. CO2 in Seawater: Equilibrium, Kinetics, Isotopes (Elsevier, 2001).

  95. Zeebe, R. E. & Tyrrell, T. History of carbonate ion concentration over the last 100 million years II: revised calculations and new data. Geochim. Cosmochim. Acta 257, 373–392 (2019).

    Article  Google Scholar 

  96. Sarmiento, J. L. Ocean Biogeochemical Dynamics (Princeton Univ. Press, 2013).

  97. Pierrot, D. E., Lewis, E. & Wallace, D. W. R. MS Excel Program Developed for CO2 System Calculations ORNL/CDIAC-105a (Carbon Dioxide Information Analysis Center, Oak Ridge National Laboratory, U.S. Department of Energy, 2006); https://cdiac.ess-dive.lbl.gov/ftp/co2sys/CO2SYS_calc_XLS_v2.1/

  98. Huck, C. E., van de Flierdt, T., Bohaty, S. M. & Hammond, S. J. Antarctic climate, Southern Ocean circulation patterns, and deep water formation during the Eocene. Paleoceanography 32, 674–691 (2017).

    Article  Google Scholar 

Download references

Acknowledgements

This study used samples and data provided by the International Ocean Discovery Program (IODP). We thank the IODP Gulf Coast Repository and Kochi Core Center for providing the sediment samples from the Southern Ocean, and H. Pfuhl for providing site 1170 foraminiferal stable isotope data. Financial support for this study was provided by Texas A&M University Triads for Transformation Program to Y.G.Z. and Texas Sea Grant Grants-In-Aid of Graduate Research Program (NA18OAR4170088) to B.K. We thank C. Maupin at the Stable Isotope Geosciences Facility, S. Sweet and A. Knap at the Geochemical and Environmental Research Group for their support and advice on the mass spectrometry analyses. We are also grateful to N. Randle for proofreading the manuscript and E. Grossman, Z. Lu and N. Slowey for helpful discussions.

Author information

Authors and Affiliations

Authors

Contributions

B.K. conducted lipid biomarker and isotopic measurements, analysed the data, performed model calculations and wrote the manuscript. Y.G.Z. conceived the study, analysed the data and wrote the manuscript.

Corresponding author

Correspondence to Yi Ge Zhang.

Ethics declarations

Competing interests

The authors declare no competing interests.

Peer review

Peer review information

Nature Geoscience thanks Kai-Uwe Hinrichs, John Kessler and the other, anonymous, reviewer(s) for their contribution to the peer review of this work. Primary Handling Editor: Tom Richardson, in collaboration with the Nature Geoscience team.

Additional information

Publisher’s note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Extended data

Extended Data Fig. 1 Potential age shifts of high Methane Index (MI) samples considering ancient SMTZ depths.

a, Sites 1168; b, Site 1170; and c, Site U1356. Gray vertical bars indicate high MI intervals without age adjustment whereas the red vertical bars indicate age adjustment based on the MI-SMTZ depth regression curves and sedimentation rate (Methods; Extended Data Fig. 2). Benthic δ18O from each site were used for comparison, except for Site U1356 where the global benthic stacked δ18O record19 was used. Note that most age shifts are negligible. Blue dashed square highlights the Mi-1 event interval.

Extended Data Fig. 2 Modern relationships between MI and SMTZ depth.

Data were compiled from marine sites where both modern SMTZ depth and GDGTs data were available. Red: sites located in tropical-to-temperate oceans, including Gulf of Mexico16,66, Mediterranean Sea67,68, Aarhus Bay69 and Peru margin;65 and blue: sites located in the Arctic Ocean (>60 °N), including Norwegian Sea70, Canadian Beaufort Sea71 and Chukchi Sea72.

Extended Data Fig. 3 Total organic carbon (TOC, wt%) contents of our studied sites.

From left to right, TOC contents of Sites 1168 (Ref. 47) and 1170 (Ref. 48), and U1356 (Ref. 49) are shown. Depths in meters below seafloor (mbsf) associated with the OMB are indicated by gray lines.

Extended Data Fig. 4 Reconstructed 1° x 1° grid paleobathymetry at 23 Ma with the seafloor area of 600-3000 m water depth.

Paleobathymetry data are from Ref. 34. Mid-ocean ridges and terrestrial lakes were excluded from our considerations.

Extended Data Fig. 5 Varying percentage of methane oxidized aerobically and its impact on seawater chemistry (pH and CO2).

The total amount of methane released during OMB was calculated to be 199 ± 35 Gt. Red and blue areas indicate the propagated uncertainties. Gray area indicates the range between AOM-dominant environments (10%) and high methane seepage settings (80%). Refer to “Methods” for full description of our calculations and “Supplementary Table 1” for global ocean seawater parameters used in the calculations.

Extended Data Fig. 6 Benthic carbon isotope records and methane-related biomarkers at Sites 1168 and 1170.

a, carbon isotope (δ13C) of benthic foraminifera at Site 1170 (light blue; Ref. 26) and stacked δ13C (blue; Ref. 19); b, Methane Index (MI) values of Sites 1168 (black) and 1170 (white); and c, concentration of hop-17(21)-ene (white bar; structure shown), archaeol (black bar; structure shown) and their compound-specific carbon isotopic (δ13C) signatures of Site 1168; compounds that are under detection limit are not shown here (Extended Data Table 2). Note that high MI values first appeared at ~ 23 Ma coinciding with a δ13C maxima, and continued into the δ13C decline phase. Yellow area highlights the Mi-1 event, and dashed vertical line indicates the carbonate dissolution event41.

Extended Data Table 1 Age controls of our studied sites
Extended Data Table 2 Lipid biomarker and compound-specific carbon isotope data of Sites 1168 and U1356
Extended Data Table 3 Calculations of regional and global gas hydrate reservoir size changes in response to an eustatic sea-level drop of 50 m
Extended Data Table 4 Calculated impact of aerobic oxidation of methane (199 ± 35 Gt of C) on seawater chemistry and atmospheric CO2

Supplementary information

Supplementary Information

Supplementary Figs. 1–5 and Table 1.

Supplementary Data 1

Lipid biomarker and compound-specific carbon isotope data.

Rights and permissions

Reprints and Permissions

About this article

Verify currency and authenticity via CrossMark

Cite this article

Kim, B., Zhang, Y.G. Methane hydrate dissociation across the Oligocene–Miocene boundary. Nat. Geosci. 15, 203–209 (2022). https://doi.org/10.1038/s41561-022-00895-5

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1038/s41561-022-00895-5

Search

Quick links

Nature Briefing

Sign up for the Nature Briefing newsletter — what matters in science, free to your inbox daily.

Get the most important science stories of the day, free in your inbox. Sign up for Nature Briefing