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.

Magnetism in cold subducting slabs at mantle transition zone depths

Nature volume 570, pages 102–106 (2019)Cite this article

Subjects

Abstract

The Earth’s crust–mantle boundary, the Mohorovičić discontinuity, has been traditionally considered to be the interface between the magnetic crust and the non-magnetic mantle1. However, this assumption has been questioned by geophysical observations2,3 and by the identification of magnetic remanence in mantle xenoliths4, which suggest mantle magnetic sources. Owing to their high critical temperatures, iron oxides are the only potential sources of magnetic anomalies at mantle depths5. Haematite (α-Fe2O3) is the dominant iron oxide in subducted lithologies at depths of 300 to 600 kilometres, delineated by the thermal decomposition of magnetite and the crystallization of a high-pressure magnetite phase deeper than about 600 kilometres6. The lack of data on the magnetic properties of haematite at relevant pressure–temperature conditions, however, hinders the identification of magnetic boundaries within the mantle and their contribution to observed magnetic anomalies. Here we apply synchrotron Mössbauer source spectroscopy in laser-heated diamond anvil cells to investigate the magnetic transitions and critical temperatures in Fe2O3 polymorphs7 at pressures and temperatures of up to 90 gigapascals and 1,300 kelvin, respectively. Our results show that haematite remains magnetic at the depth of the transition zone in the Earth’s mantle in cold or very cold subduction geotherms, forming a frame of deep magnetized rocks in the West Pacific region. The deep magnetic sources spatially correlate with preferred paths of the Earth’s virtual geomagnetic poles during reversals8 that might not reflect the geometry of the transitional field. Rather, the paths might be an artefact caused by magnetized haematite-bearing rocks in cold subducting slabs at mid-transition zone depths. Such deep sources should be taken into account when carrying out inversions of the Earth’s geomagnetic data9, and especially in studies of planetary bodies that no longer have a dynamo10, such as Mars.

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

Relevant articles

Open Access articles citing this article.

Access options

Rent or buy this article

Prices vary by article type

from$1.95

to$39.95

Learn more

Prices may be subject to local taxes which are calculated during checkout

Fig. 1: SMS spectra of Fe2O3 polymorphs.
Fig. 2: Critical temperatures in α-Fe2O3.
Fig. 3: Magnetic phase diagram of Fe2O3.
Fig. 4: The region of a magnetic transition zone.

Data availability

All ASCII files of the unprocessed spectra used in this study are available in the Extended Data.

References

  1. Wasilewski, P. J., Thomas, H. H. & Mayhew, M. A. The Moho as a magnetic boundary. Geophys. Res. Lett. 6, 541–544 (1979).

    Article  ADS  Google Scholar 

  2. Blakely, R. J., Brocher, T. M. & Wells, R. E. Subduction-zone magnetic anomalies and implications for hydrated forearc mantle. Geology 33, 445–448 (2005).

    Article  ADS  Google Scholar 

  3. Chiozzi, P., Matsushima, J., Okubo, Y., Pasquale, V. & Verdoya, M. Curie-point depth from spectral analysis of magnetic data in central–southern Europe. Phys. Earth Planet. Inter. 152, 267–276 (2005).

    Article  ADS  Google Scholar 

  4. Ferré, E. C. et al. The magnetism of mantle xenoliths and potential implications for sub-Moho magnetic sources. Geophys. Res. Lett. 40, 105–110 (2013).

    Article  ADS  Google Scholar 

  5. Dunlop, D. J. & Kletetschka, G. Multidomain hematite: a source of planetary magnetic anomalies? Geophys. Res. Lett. 28, 3345–3348 (2001).

    Article  CAS  ADS  Google Scholar 

  6. Woodland, A. B., Frost, D. J., Trots, D. M., Klimm, K. & Mezouar, M. In situ observation of the breakdown of magnetite (Fe3O4) to Fe4O5 and hematite at high pressures and temperatures. Am. Mineral. 97, 1808–1811 (2012).

    Article  CAS  ADS  Google Scholar 

  7. Bykova, E. et al. Structural complexity of simple Fe2O3 at high pressures and temperatures. Nat. Commun. 7, 10661 (2016).

    Article  CAS  ADS  Google Scholar 

  8. Laj, C., Mazaud, A., Weeks, R., Fuller, M. & Herrero-Bervera, E. Geomagnetic reversal paths. Nature 359, 111–112 (1992).

    Article  ADS  Google Scholar 

  9. Li, Y. & Oldenburg, D. W. 3-D inversion of magnetic data. Geophysics 61, 394–408 (1996).

    Article  ADS  Google Scholar 

  10. Stevenson, D. J. Mars’ core and magnetism. Nature 412, 214–219 (2001).

    Article  CAS  ADS  Google Scholar 

  11. Ferré, E. C. et al. Eight good reasons why the uppermost mantle could be magnetic. Tectonophysics 624–625, 3–14 (2014).

    Article  ADS  Google Scholar 

  12. Klein, F. et al. Magnetite in seafloor serpentinite−some like it hot. Geology 42, 135–138 (2014).

    Article  CAS  ADS  Google Scholar 

  13. Lécuyer, C. Long-term fluxes and budget of ferric iron: implication for the redox states of the Earth’s mantle and atmosphere. Earth Planet. Sci. Lett. 165, 197–211 (1999).

    Article  ADS  Google Scholar 

  14. Uenver-Thiele, L., Woodland, A. B., Boffa Ballaran, T., Miyajima, N. & Frost, D. J. Phase relations of Fe-Mg spinels including new high-pressure post-spinel phases and implications for natural samples. Am. Mineral. 102, 2054–2064 (2017).

    Article  ADS  Google Scholar 

  15. Klotz, S., Strässle, T. & Hansen, T. Pressure dependence of Morin transition in α-Fe2O3 hematite. Europhys. Lett. 104, 16001 (2013).

    Article  ADS  Google Scholar 

  16. van der Woude, F. Mössbauer effect in α-Fe2O3. Phys. Status Solidi 17, 417–432 (1966).

    Article  Google Scholar 

  17. Fukao, Y., Obayashi, M. & Nakakuki, T. Stagnant slab. Annu. Rev. Earth Planet. Sci. 37, 19–46 (2009).

    Article  CAS  ADS  Google Scholar 

  18. Ovsyannikov, S. V. et al. Charge-ordering transition in iron oxide Fe4O5 involving competing dimer and trimer formation. Nat. Chem. 8, 501 (2016).

    Article  CAS  Google Scholar 

  19. Samara, G. A. & Giardini, A. A. Effect of pressure on the Néel temperature of magnetite. Phys. Rev. 186, 577–580 (1969).

    Article  CAS  ADS  Google Scholar 

  20. Kantor, I. et al. FeO and MnO high-pressure phase diagrams: relations between structural and magnetic properties. Phase Transit. 80, 1151–1163 (2007).

    Article  CAS  Google Scholar 

  21. Liu, J. Z. Morin transition in hematite doped with iridium ions. J. Magn. Magn. Mater. 54–57, 901–902 (1986).

    Article  ADS  Google Scholar 

  22. Besser, P. J. & Morrish, A. H. Spin flopping in synthetic hematite crystals. Phys. Lett. 13, 289–290 (1964).

    Article  CAS  ADS  Google Scholar 

  23. Gubbins, D. & Herrero-Bervera, E. Encyclopedia of Geomagnetism and Paleomagnetism (Springer, 2007).

  24. Minyuk, P. S., Subbotnikova, T. V., Brown, L. L. & Murdock, K. J. High-temperature thermomagnetic properties of vivianite nodules, Lake El’gygytgyn, Northeast Russia. Clim. Past 9, 433–446 (2013).

    Article  Google Scholar 

  25. Robinson, P., Harrison, R. J., McEnroe, S. A. & Hargraves, R. B. Lamellar magnetism in the haematite–ilmenite series as an explanation for strong remanent magnetization. Nature 418, 517–520 (2002).

    Article  CAS  ADS  Google Scholar 

  26. Kiss, J., Szarka, L. & Prácser, E. Second-order magnetic phase transition in the Earth. Geophys. Res. Lett. 32, L24310 (2005).

    Article  ADS  Google Scholar 

  27. McEnroe, S. A., Langenhorst, F., Robinson, P., Bromiley, G. D. & Shaw, C. S. J. What is magnetic in the lower crust? Earth Planet. Sci. Lett. 226, 175–192 (2004).

    Article  CAS  ADS  Google Scholar 

  28. Chaikin, P. & Lubensky, T. Principles of Condensed Matter Physics (Cambridge Univ. Press, 2000).

  29. Hulot, G., Finlay, C. C., Constable, C. G., Olsen, N. & Mandea, M. The magnetic field of planet Earth. Space Sci. Rev. 152, 159–222 (2010).

    Article  CAS  ADS  Google Scholar 

  30. Langereis, C. G., van Hoof, A. A. M. & Rochette, P. Longitudinal confinement of geomagnetic reversal paths as a possible sedimentary artefact. Nature 358, 226–230 (1992).

    Article  ADS  Google Scholar 

  31. Prévot, M. & Camps, P. Absence of preferred longitude sectors for poles from volcanic records of geomagnetic reversals. Nature 366, 53–57 (1993).

    Article  ADS  Google Scholar 

  32. Love, J. J. Paleomagnetic volcanic data and geometric regularity of reversals and excursions. J. Geophys. Res. Solid Earth 103, 12435–12452 (1998).

    Article  Google Scholar 

  33. Obayashi, M. et al. Finite frequency whole mantle P wave tomography: Improvement of subducted slab images. Geophys. Res. Lett. 40, 5652–5657 (2013).

    Article  ADS  Google Scholar 

  34. Frost, D. et al. A new large-volume multianvil system. Phys. Earth Planet. Inter. 143–144, 507–514 (2004).

    Article  ADS  Google Scholar 

  35. Kantor, I. et al. BX90: a new diamond anvil cell design for X-ray diffraction and optical measurements. Rev. Sci. Instrum. 83, 125102 (2012).

    Article  CAS  ADS  Google Scholar 

  36. Dewaele, A., Torrent, M., Loubeyre, P. & Mezouar, M. Compression curves of transition metals in the Mbar range: experiments and projector augmented-wave calculations. Phys. Rev. B 78, 104102 (2008).

    Article  ADS  Google Scholar 

  37. Kurnosov, A. et al. A novel gas-loading system for mechanically closing of various types of diamond anvil cells. Rev. Sci. Instrum. 79, 045110 (2008).

    Article  ADS  Google Scholar 

  38. Kupenko, I. et al. Portable double-sided laser-heating system for Mössbauer spectroscopy and X-ray diffraction experiments at synchrotron facilities with diamond anvil cells. Rev. Sci. Instrum. 83, 124501 (2012).

    Article  CAS  ADS  Google Scholar 

  39. Heinz, D. L. & Jeanloz, R. in High-Pressure Research in Mineral Physics: A Volume in Honor of Syun-iti Akimoto 113–127 (American Geophysical Union, 1987).

  40. Rüffer, R. & Chumakov, A. I. Nuclear resonance beamline at ESRF. Hyperfine Interact. 97–98, 589–604 (1996).

    Article  ADS  Google Scholar 

  41. Potapkin, V. et al. The 57Fe synchrotron Mössbauer source at the ESRF. J. Synchrotron Radiat. 19, 559–569 (2012).

    Article  CAS  Google Scholar 

  42. Prescher, C., McCammon, C. & Dubrovinsky, L. MossA : a program for analyzing energy-domain Mössbauer spectra from conventional and synchrotron sources. J. Appl. Cryst. 45, 329–331 (2012).

    Article  CAS  Google Scholar 

  43. Sturhahn, W. CONUSS and PHOENIX: evaluation of nuclear resonant scattering data. Hyperfine Interact. 125, 149–172 (2000).

    Article  CAS  Google Scholar 

  44. Maradudin, A. A., Flinn, P. A. & Ruby, S. Velocity shift of the Mössbauer resonance. Phys. Rev. 126, 9–23 (1962).

    Article  CAS  ADS  Google Scholar 

  45. Pasternak, M. P. et al. Breakdown of the Mott-Hubbard state in Fe2O3: a first-order insulator-metal transition with collapse of magnetism at 50 GPa. Phys. Rev. Lett. 82, 4663–4666 (1999).

    Article  CAS  ADS  Google Scholar 

  46. Kurimoto, K., Nasu, S., Nagatomo, S., Endo, S. & Fujita, F. E. Mössbauer study of α-Fe2O3 under ultra-high pressure. Phys. B+C 139–140, 495–498 (1986).

    Article  ADS  Google Scholar 

  47. Eibschütz, M. Critical-point behavior of FeBO3 single crystals by Mössbauer effect. J. Appl. Phys. 41, 1276 (1970).

    Article  ADS  Google Scholar 

  48. Callen, E. & Callen, H. Ferromagnetic transitions and the one-third-power law. J. Appl. Phys. 36, 1140 (1965).

    Article  CAS  ADS  Google Scholar 

  49. Syracuse, E. M., van Keken, P. E. & Abers, G. A. The global range of subduction zone thermal models. Phys. Earth Planet. Inter. 183, 73–90 (2010).

    Article  ADS  Google Scholar 

  50. King, S. D., Frost, D. J. & Rubie, D. C. Why cold slabs stagnate in the transition zone. Geology 43, 231–234 (2015).

    Article  ADS  Google Scholar 

  51. Vasiukov, D. M. et al. Pressure-induced spin pairing transition of Fe3+ in oxygen octahedra. Preprint at https://arxiv.org/abs/1710.03192 (2017).

  52. Ito, E. et al. Determination of high-pressure phase equilibria of Fe2O3 using the Kawai-type apparatus equipped with sintered diamond anvils. Am. Mineral. 94, 205–209 (2009).

    Article  CAS  ADS  Google Scholar 

  53. Lord, O. T. T., Walter, M. J. J., Dasgupta, R., Walker, D. & Clark, S. M. M. Melting in the Fe–C system to 70 GPa. Earth Planet. Sci. Lett. 284, 157–167 (2009).

    Article  CAS  ADS  Google Scholar 

Download references

Acknowledgements

We thank C. Finlay and A. Hirt for their comments and discussions in an early stage of this work. We thank E. Bykova for the selection of single crystals by X-ray diffraction and verification of the phases in laser-heated diamond anvil cells. This work was supported by the University of Münster, the German Research Foundation and the German Federal Ministry of Education and Research. We acknowledge the European Synchrotron Radiation Facility for the provision of synchrotron radiation facilities and J. Jacobs from the Sample Environment Service-HP laboratory for technical support.

Reviewer information

Nature thanks Takaya Mitsui and the other anonymous reviewer(s) for their contribution to the peer review of this work.

Author information

Authors and Affiliations

  1. Institut für Mineralogie, University of Münster, Münster, Germany

    I. Kupenko & C. Sanchez-Valle

  2. Bayerisches Geoinstitut, University of Bayreuth, Bayreuth, Germany

    G. Aprilis, D. M. Vasiukov, C. McCammon, S. Chariton, V. Cerantola & L. Dubrovinsky

  3. Material Physics and Technology at Extreme Conditions, Laboratory of Crystallography, University of Bayreuth, Bayreuth, Germany

    G. Aprilis & D. M. Vasiukov

  4. Department of Physics and Astronomy, Rutgers University, Piscataway, NJ, USA

    D. M. Vasiukov

  5. ESRF—The European Synchrotron, Grenoble, France

    V. Cerantola, A. I. Chumakov & R. Rüffer

  6. Technical University of Denmark, Kongens Lyngby, Denmark

    I. Kantor

Authors
  1. I. Kupenko
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. G. Aprilis
    View author publications

    You can also search for this author in PubMed Google Scholar

  3. D. M. Vasiukov
    View author publications

    You can also search for this author in PubMed Google Scholar

  4. C. McCammon
    View author publications

    You can also search for this author in PubMed Google Scholar

  5. S. Chariton
    View author publications

    You can also search for this author in PubMed Google Scholar

  6. V. Cerantola
    View author publications

    You can also search for this author in PubMed Google Scholar

  7. I. Kantor
    View author publications

    You can also search for this author in PubMed Google Scholar

  8. A. I. Chumakov
    View author publications

    You can also search for this author in PubMed Google Scholar

  9. R. Rüffer
    View author publications

    You can also search for this author in PubMed Google Scholar

  10. L. Dubrovinsky
    View author publications

    You can also search for this author in PubMed Google Scholar

  11. C. Sanchez-Valle
    View author publications

    You can also search for this author in PubMed Google Scholar

Contributions

I. Kupenko and L.D. designed and organized the project. L.D. contributed the samples. I. Kupenko, G.A., V.C. and I. Kantor prepared the high-pressure, high-temperature experiments. I. Kupenko, G.A., D.M.V., C.McC., S.C., V.C., I. Kantor, A.I.C. and R.R. conducted the SMS measurements. I. Kupenko and D.M.V. analysed the Mössbauer data. I. Kupenko and C.S.-V. interpreted the results and wrote the manuscript with contributions from all authors.

Corresponding author

Correspondence to I. Kupenko.

Ethics declarations

Competing interests

The authors declare no competing interests.

Additional information

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

Extended data figures and tables

Extended Data Fig. 1 Pressure–temperature coverage of the data.

Phase boundaries are defined according to ref. 7 with the exception of the α-Fe2O3 to ι-Fe2O3 boundary, which is taken from ref. 52. Filled symbols show the pressure–temperature conditions investigated in this study. Blue, α-Fe2O3; green, ι-Fe2O3; yellow, ζ-Fe2O3; red, η-Fe2O3; orange, θ-Fe2O3. Coexisting phases are indicated by two-coloured symbols. The crystallographic designation of the phases is provided in the Methods. The error bars are one standard error.

Extended Data Fig. 2 SMS spectra of α-Fe2O3.

Temperature evolution of SMS spectra of α-Fe2O3 at 19.4(4) GPa (a) and at 24.5(2) GPa (b). Temperatures marked by asterisks were determined by spectroradiometry. The broadening of the absorption lines above 800 K is related to the enhanced sensitivity of Bhf to temperature gradients owing to the steeper temperature dependence close to TN.

Source data

Extended Data Fig. 3 SMS spectra of ι-Fe2O3.

Temperature evolution of SMS spectra of ι-Fe2O3 at 40(1) GPa (a) and at 46(1) GPa (b). Heating of ι-Fe2O3 at 46(1) GPa above 500 K causes its transformation into ζ-Fe2O3. The ζ-Fe2O3 phase can be cooled down to around 500 K, but it transforms back to ι-Fe2O3 upon further cooling. Temperatures marked by asterisks and daggers were determined by spectroradiometry or estimated using the laser power53, respectively.

Source data

Extended Data Fig. 4 SMS spectra of η-Fe2O3.

Temperature evolution of SMS spectra of η-Fe2O3 together with the residue of an untransformed θ-Fe2O3 and the product of partial decomposition of the sample (see Fig. 1 for details) at 75.1(5) GPa (a) and at 90.7(5) GPa (b). Temperatures marked by daggers were estimated from the laser power.

Source data

Extended Data Fig. 5 Hyperfine magnetic field Bhf in Fe2O3 high-pressure polymorphs.

Temperature dependence of Bhf in ι-Fe2O3 (a) and η-Fe2O3 (b) at the indicated pressures. Filled symbols correspond to temperatures determined from the SMS internal thermometer (equation (2). Half-filled symbols correspond to temperatures estimated from the calibrated laser power and were excluded from the fit of the critical temperatures Tc. Lines are fits of the experimental data to equation (4) in the 0.5Tc < T < 0.99Tc range. The crystallographic designation of the phases is provided in the Methods. Data at one atmosphere are from ref. 16. The error bars are one standard error.

Source data

Extended Data Table 1 Hyperfine parameters of Fe2O3 polymorphs and of the novel mixed-valence iron oxide phase at room temperature (25 °C)
Full size table

Source data

Rights and permissions

Reprints and Permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Kupenko, I., Aprilis, G., Vasiukov, D.M. et al. Magnetism in cold subducting slabs at mantle transition zone depths. Nature 570, 102–106 (2019). https://doi.org/10.1038/s41586-019-1254-8

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1038/s41586-019-1254-8

This article is cited by

Comments

By submitting a comment you agree to abide by our Terms and Community Guidelines. If you find something abusive or that does not comply with our terms or guidelines please flag it as inappropriate.

Search

Advanced 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