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.

  • Article
  • Published:

A poorly mixed mantle transition zone and its thermal state inferred from seismic waves

Nature Geoscience volume 14, pages 949–955 (2021)Cite this article

Subjects

Abstract

The abrupt changes in mineralogical properties across the Earth’s mantle transition zone substantially impact convection and thermochemical fluxes between the upper and lower mantle. While the 410-km discontinuity at the top of the mantle transition zone is detected with all types of seismic waves, the 660-km boundary is mostly invisible to underside P-wave reflections (P660P). The cause for this observation is debated. The dissociation of ringwoodite and garnet into lower-mantle minerals both contribute to the ‘660’ visibility; only the garnet reaction favours material exchanges across the discontinuity. Here, we combine large datasets of SS and PP precursors, mineralogical modelling and data-mining techniques to obtain a global thermal map of the mantle transition zone, and explain the lack of P660P visibility. We find that its prevalent absence requires a chemically unequilibrated mantle, and its visibility in few locations is associated with potential temperatures greater than 1,800 K. Such temperatures occur in approximately 0.6% of Earth, indicating that the 660 is dominated by ringwoodite decomposition, which tends to impede mantle flow. We find broad regions with elevated temperatures beneath the Pacific surrounded by major volcanic hotspots, indicating plume retention and ponding of hot materials in the mantle transition zone.

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

Access options

Buy this article

  • Purchase on Springer Link
  • Instant access to full article PDF
Buy now

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

Fig. 1: SS and PP precursory reflections underneath the 410 and 660, and global data coverage.
Fig. 2: Global observations of the 410 and 660 in SS and PP data.
Fig. 3: Effects of temperature on MTZ mineralogical phase transitions, and SS and PP precursors.
Fig. 4: Thermal model of the MTZ and implications for global mantle circulation.

Similar content being viewed by others

Data availability

Waveform data are publicly available from the IRIS Data Management Center (NSF grant EAR-1063471). Measurements of the 410 and 660 km discontinuities, the thermal map and velocity models are available from the ISC Repository (https://doi.org/10.31905/7M3LMG8X).

Code availability

A downsampled database of synthetic seismograms for mineral-physics models is available from https://zenodo.org/record/5512035. A simplified version of the adaptive stacking code is available from https://zenodo.org/record/5512805. The full database and software are available from the corresponding author upon request.

References

  1. Burke, K., Steinberger, B., Torsvik, T. & Smethurst, M. Plume generation zones at the margins of large low shear velocity provinces on the core–mantle boundary. Earth Planet. Sci. Lett. 265, 49–60 (2008).

    Article  Google Scholar 

  2. Courtillot, V., Davaille, A., Besse, J. & Stock, J. Three distinct types of hotspots in the Earth’s mantle. Earth Planet. Sci. Lett. 205, 295–308 (2003).

    Article  Google Scholar 

  3. Koppers, A., Staudigel, H., Pringle, M. & Wijbrans, J. Short-lived and discontinuous intraplate volcanism in the South Pacific: hot spots or extensional volcanism? Geochem. Geophys. Geosys. https://doi.org/10.1029/2003GC000533 (2003).

  4. Nakagawa, T. & Buffett, B. Mass transport mechanism between the upper and lower mantle in numerical simulations of thermochemical mantle convection with multicomponent phase changes. Earth Planet. Sci. Lett. 230, 11–27 (2005).

    Article  Google Scholar 

  5. Farnetani, C. & Samuel, H. Beyond the thermal plume paradigm. Geophys. Res. Lett. https://doi.org/10.1029/2005GL022360 (2005).

  6. Dannberg, J. & Sobolev, S. Low-buoyancy thermochemical plumes resolve controversy of classical mantle plume concept. Nat. Commun. 6, 6960 (2015).

    Article  Google Scholar 

  7. Bina, C. & Helffrich, G. Phase transition Clapeyron slopes and transition zone seismic discontinuity topography. J. Geophys. Res. 99, 15853–15860 (1994).

    Article  Google Scholar 

  8. Christensen, U. Effects of phase transitions on mantle convection. Annu. Rev. Earth. Planet. Sci. 23, 65–87 (1995).

    Article  Google Scholar 

  9. Tackley, P., Stevenson, D., Glatzmaier, G. & Schubert, G. Effects of an endothermic phase transition at 670 km depth in a spherical model of convection in the Earth’s mantle. Nature 361, 699–704 (1993).

    Article  Google Scholar 

  10. Bercovici, D., Schubert, G. & Tackley, P. On the penetration of the 660 km phase change by mantle downflows. Geophys. Res. Lett. 20, 2599–2602 (1993).

    Article  Google Scholar 

  11. Fukao, Y. & Obayashi, M. Subducted slabs stagnant above, penetrating through, and trapped below the 660 km discontinuity. J. Geophys. Res. 118, 5920–5938 (2013).

    Article  Google Scholar 

  12. Cao, Q., van der Hilst, R., de Hoop, M. V. & Shim, S. Seismic imaging of transition zone discontinuities suggests hot mantle west of Hawaii. Science 332, 1068–1071 (2011).

    Article  Google Scholar 

  13. Ritsema, J., Deuss, A., van Heijst, H. & Woodhouse, J. S40RTS: a degree-40 shear-velocity model for the mantle from new Rayleigh wave dispersion, teleseismic traveltime and normal-mode splitting function measurements. Geophys. J. Int. 184, 1223–1236 (2011).

    Article  Google Scholar 

  14. French, S. & Romanowicz, B. Whole-mantle radially anisotropic shear-velocity structure from spectral-element waveform tomography. Geophys. J. Int. 199, 1303–1327 (2014).

    Article  Google Scholar 

  15. Ballmer, M. D., Schmerr, N. C., Nakagawa, T. & Ritsema, J. Compositional mantle layering revealed by slab stagnation at ~1000-km depth. Sci. Adv. https://doi.org/10.1126/sciadv.1500815 (2015).

  16. Tosi, N. & Yuen, D. Bent-shaped plumes and horizontal channel flow beneath the 660 km discontinuity. Earth Planet. Sci. Lett. 312, 348–359 (2011).

    Article  Google Scholar 

  17. Jenkins, J., Cottaar, S., White, R. & Deuss, A. Depressed mantle discontinuities beneath Iceland: evidence of a garnet controlled 660 km discontinuity? Earth Planet. Sci. Lett. 433, 159–168 (2016).

    Article  Google Scholar 

  18. Hirose, K. Phase transitions in pyrolitic mantle around 670-km depth: implications for upwelling of plumes from the lower mantle. J. Geophys. Res. 107, 2078 (2002).

    Google Scholar 

  19. Weidner, D. J. & Wang, Y. Chemical- and Clapeyron-induced buoyancy at the 660 km discontinuity. J. Geophys. Res. Solid Earth 103, 7431–7441 (1998).

    Article  Google Scholar 

  20. Shearer, P. & Flanagan, M. Seismic velocity and density jumps across the 410- and 660-kilometer discontinuities. Science 285, 1545–1548 (1999).

    Article  Google Scholar 

  21. Houser, C. & Williams, Q. Reconciling Pacific 410 and 660 km discontinuity topography, transition zone shear velocity patterns, and mantle phase transitions. Earth Planet. Sci. Lett. 296, 255–266 (2010).

    Article  Google Scholar 

  22. Ritsema, J., Xu, W., Stixrude, L. & Lithgow-Bertelloni, C. Estimates of the transition zone temperature in a mechanically mixed upper mantle. Earth Planet. Sci. Lett. 277, 244–252 (2009).

    Article  Google Scholar 

  23. Deuss, A., Redfern, S., Chambers, K. & Woodhouse, J. The nature of the 660-kilometer discontinuity in Earth’s mantle from global seismic observations of PP precursors. Science 311, 19–201 (2006).

    Article  Google Scholar 

  24. Munch, F., Khan, A., Tauzin, B., van Driel, M. & Giardini, D. Seismological evidence for thermo-chemical heterogeneity in Earth’s continental mantle. Earth Planet. Sci. Lett. 539, 116240 (2020).

    Article  Google Scholar 

  25. Schmerr, N. & Garnero, E. J. Upper mantle discontinuity topography from thermal and chemical heterogeneity. Science 318, 623–626 (2007).

    Article  Google Scholar 

  26. Wu, W., Ni, S. & Irving, J. C. E. Inferring Earth’s discontinuous chemical layering from the 660-kilometer boundary topography. Science 363, 763–740 (2019).

    Article  Google Scholar 

  27. Waszek, L., Schmerr, N. & Ballmer, M. Global observations of reflectors in the mid-mantle with implications for mantle structure and dynamics. Nat. Commun. 9, 385 (2018).

    Article  Google Scholar 

  28. Bassin, C., Laske, G. & Masters, G. The current limits of resolution for surface wave tomography in North America. EOS Trans. AGU 81, F897 (2000).

    Google Scholar 

  29. Dziewoński, A. & Anderson, D. Preliminary reference Earth model. Phys. Earth Planet. Int. 25, 297–356 (1981).

    Article  Google Scholar 

  30. Lessing, S., Thomas, C., Saki, M., Schmerr, N. & Vanacore, E. On the difficulties of detecting PP precursors. Geophys. J. Int. 201, 1666–1681 (2015).

    Article  Google Scholar 

  31. Connolly, J. A. D. Computation of phase equilibria by linear programming: a tool for geodynamic modeling and its application to subduction zone decarbonation. Earth Planet. Sci. Lett. 236, 524–541 (2005).

    Article  Google Scholar 

  32. Stixrude, L. & Lithgow-Bertelloni, C. Thermodynamics of mantle minerals – II. Phase equilibria. Geophys. J. Int. 184, 1180–1213 (2011).

    Article  Google Scholar 

  33. Baker, M. B. & Stolper, E. M. Determining the composition of high-pressure mantle melts using diamond aggregates. Geochim. Cosmochim. Acta 58, 2811–2827 (1994).

    Article  Google Scholar 

  34. Ekström, G., Nettles, M. & Dziewonski, A. The global CMT project 2004-2010: centroid-moment tensors for 13,017 earthquakes. Phys. Earth Planet. Inter. 200-201, 1–9 (2012).

    Article  Google Scholar 

  35. Gale, A., Dalton, C. A., Langmuir, C. H., Su, Y. & Schilling, J. The mean composition of ocean ridge basalts. Geochem. Geophys. Geosys. https://doi.org/10.1029/2012GC004334 (2013).

  36. Afonso, J. C., Fernandez, M., Ranalli, G., Griffin, W. L. & Connolly, J. A. D. Integrated geophysical–petrological modeling of the lithosphere and sublithospheric upper mantle: methodology and applications. Geochem. Geophys. Geosys. https://doi.org/10.1029/2007GC001834 (2008).

  37. Ringwood, A. E. A model for the upper mantle. J. Geophy. Res. 67, 857–867 (1962).

    Article  Google Scholar 

  38. Stixrude, L. & Lithgow-Bertelloni, C. Geophysics of chemical heterogeneity in the mantle. Annu. Rev. Earth. Planet. Sci. 40, 569–595 (2012).

    Article  Google Scholar 

  39. Xu, W., Lithgow-Bertelloni, C., Stixrude, L. & Ritsema, J. The effect of bulk composition and temperature on mantle seismic structure. Earth Planet. Sci. Lett. 275, 70–79 (2008).

    Article  Google Scholar 

  40. Herzberg, C. et al. Temperatures in ambient mantle and plumes: constraints from basalts, picrites, and komatiites. Geochem. Geophys. Geosys. https://doi.org/10.1029/2006GC001390 (2007).

  41. Hirose, K., Fei, Y., Ma, Y. & Mao, H. K. The fate of subducted basaltic crust in the Earth’s lower mantle. Nature 397, 53–56 (1999).

    Article  Google Scholar 

  42. Yan, J., Ballmer, M. D. & Tackley, P. J. The evolution and distribution of recycled oceanic crust in the Earth’s mantle: insight from geodynamic models. Earth Planet. Sci. Lett. 537, 116171 (2020).

    Article  Google Scholar 

  43. Thio, V., Cobden, L. & Trampert, J. Seismic signature of a hydrous mantle transition zone. Phys. Earth. Planet. Inter. 250, 46–63 (2016).

    Article  Google Scholar 

  44. Schulze, K. et al. Seismically invisible water in Earth’s transition zone? Earth Planet. Sci. Lett. 498, 9–16 (2018).

    Article  Google Scholar 

  45. Müller, R. D., Royer, J. Y. & Lawver, L. A. Revised plate motions relative to the hotspots from combined Atlantic and Indian ocean hotspot tracks. Geology 21, 275–278 (1993).

    Article  Google Scholar 

  46. Davaille, A. Simultaneous generation of hotspots and superswells by convection in a heterogeneous planetary mantle. Nature 402, 756–760 (1999).

    Article  Google Scholar 

  47. Kim, S. S. & Wessel, P. New global seamount census from altimetry-derived gravity data. Geophys. J. Int. 186, 615–631 (2011).

    Article  Google Scholar 

  48. King, S. & Ritsema, J. African hot spot volcanism: small-scale convection in the upper mantle beneath cratons. Science 290, 1137–1140 (2000).

    Article  Google Scholar 

  49. Kellogg, L. H. & Turcotte, D. L. Mixing and the distribution of heterogeneities in a chaotically convecting mantle. J. Geophys. Res. Solid Earth 95, 421–432 (1990).

    Article  Google Scholar 

  50. Hofmann, A. Mantle geochemistry: the message from oceanic volcanism. Nature 385, 219–229 (1997).

    Article  Google Scholar 

  51. Marsaglia, G. Choosing a point from the surface of a sphere. Ann. Math. Stat. 43, 645–646 (1972).

    Article  Google Scholar 

  52. Efron, B. & Tibshirani, R. An Introduction to the Bootstrap (Chapman and Hall, 1991).

  53. Zoeppritz, K. On the reflection and penetration of seismic waves through unstable layers. Gött. Nachr. 1, 66–84 (1919).

    Google Scholar 

  54. Aki, K. & Richards., P. G. Quantitative Seismology: Theory and Methods, p. 801 (W. H. Freeman, 1980).

  55. Bostock, M. G. Seismic waves converted from velocity gradient anomalies in the Earth’s upper mantle. Geophys. J. Int. 138, 747–756 (1999).

    Article  Google Scholar 

  56. Tauzin, B., Pham, T. S. & Tkalčić, H. Receiver functions from seismic interferometry: a practical guide. Geophys. J. Int. 217, 1–24 (2019).

    Article  Google Scholar 

  57. Kennett, B. N. L. Seismic Wave Propagation in Stratified Media, p. 288 (ANU Press, 1983).

  58. Chapman, C. H. Yet another elastic plane-wave, layer-matrix algorithm. Geophys. J. Int. 154, 212–223 (2003).

    Article  Google Scholar 

  59. Chapman, C. H. Fundamentals of Seismic Wave Propagation (Cambridge Univ. Press, 2004).

  60. Ma, Y., Wang, R. & Zhou, H. A note on the equivalence of three major propagator algorithms for computational stability and efficiency. Earthq. Sci. 25, 55–64 (2012).

    Article  Google Scholar 

  61. Kennett, B. N. L. & Engdahl, E. Traveltimes for global earthquake location and phase identification. Geophys. J. Int. 105, 429–465 (1991).

    Article  Google Scholar 

  62. Fuchs, K. & Müller, G. Computation of synthetic seismograms with the reflectivity method and comparison with observations. Geophys. J. Int. 23, 417–433 (1971).

    Article  Google Scholar 

  63. Müller, G. The reflectivity method: a tutorial. J. Geophysics 58, 153–174 (1985).

    Google Scholar 

  64. Kikuchi, M. & Kanamori, H. Inversion of complex body waves—III. Bull. Seism. Soc. Am. 81, 2335–2350 (1991).

    Article  Google Scholar 

  65. Faul, U. H. & Jackson, I. The seismological signature of temperature and grain size variations in the upper mantle. Earth Planet. Sci. Lett. 234, 119–134 (2005).

    Article  Google Scholar 

  66. Munch, F. D., Khan, A., Tauzin, B., Zunino, A. & Giardini, D. Stochastic inversion of P‐to‐S converted waves for mantle composition and thermal structure: methodology and application. J. Geophys. Res. Solid Earth 123, 10–706 (2018).

    Google Scholar 

  67. Connolly, J. A. D. & Kerrick, D. M. Metamorphic controls on seismic velocity of subducted oceanic crust at 100–250 km depth. Earth Planet. Sci. Lett. 204, 61–74 (2002).

    Article  Google Scholar 

  68. Afonso, J. C. et al. 3-D multiobservable probabilistic inversion for the compositional and thermal structure of the lithosphere and upper mantle I: a priori information and geophysical observables. J. Geophys. Res. Solid Earth 118, 2586–2617 (2013).

    Article  Google Scholar 

  69. Stixrude, L. & Jeanloz, R. Constraints on Seismic Models from Other Disciplines - Constraints from Mineral Physics on Seismological Models (Elsevier, 2015).

  70. Connolly, J. A. D. & Khan, A. Uncertainty of mantle geophysical properties computed from phase equilibrium models. Geophys. Res. Lett. 43, 5026–5034 (2016).

    Article  Google Scholar 

Download references

Acknowledgements

L.W. acknowledges the Australian National University as host institution for the majority of this research, as well as inspiration through discussion at the Cooperative Institute for Dynamic Earth Research summer programme. CIDER-II is funded as a ‘Synthesis Center’ by the Frontiers of Earth Systems Dynamics (FESD) programme of the National Science Foundation (NSF) under grant no. EAR-1135452. The authors thank I. Campbell, L. Moresi and E. Debayle for insightful discussions and comments, and acknowledge support from a Discovery Early Career Research Award (project no. DE170100329), funded by the Australian Government (L.W.), the NSF under grant nos. EAR-1661985 and EAR-1853662 (L.W.), the European Union’s Horizon 2020 Research and Innovation programme under the Marie Skłodowska-Curie grant agreement 793824 (B.T.) and Australian Research Council grants LP170100233 and DP190102940 (J.C.A.). Calculations were performed on the ANU Terrawulf cluster, a computational facility developed with support from the AuScope initiative. AuScope Ltd is funded under the National Collaborative Research Infrastructure Strategy (NCRIS), an Australian Commonwealth Government Programme.

Author information

Authors and Affiliations

  1. Physical Sciences, James Cook University, Douglas, Queensland, Australia

    Lauren Waszek

  2. Department of Physics, New Mexico State University, Las Cruces, NM, USA

    Lauren Waszek

  3. Université de Lyon, UCBL, ENSL, CNRS, LGL-TPE, Villeurbanne, France

    Benoit Tauzin

  4. Research School of Earth Sciences, Australian National University, Acton, Australian Capital Territory, Australia

    Benoit Tauzin

  5. Department of Geology, University of Maryland College Park, College Park, MD, USA

    Nicholas C. Schmerr

  6. Department of Earth Sciences, University College London, London, UK

    Maxim D. Ballmer

  7. Institute of Geophysics, ETH Zurich, Zurich, Switzerland

    Maxim D. Ballmer

  8. Department of Earth and Planetary Sciences, Macquarie University, North Ryde, New South Wales, Australia

    Juan Carlos Afonso

Authors
  1. Lauren Waszek
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. Benoit Tauzin
    View author publications

    You can also search for this author in PubMed Google Scholar

  3. Nicholas C. Schmerr
    View author publications

    You can also search for this author in PubMed Google Scholar

  4. Maxim D. Ballmer
    View author publications

    You can also search for this author in PubMed Google Scholar

  5. Juan Carlos Afonso
    View author publications

    You can also search for this author in PubMed Google Scholar

Contributions

The study was conceived by L.W. and B.T. The datasets were compiled by L.W., partially supervised by N.C.S. B.T. wrote the adaptive stacking and synthetic modelling codes, with some contribution by L.W. B.T. and L.W. ran the synthetic experiments. L.W. implemented the analysis on observed data. All authors discussed the results and interpretations, and contributed to the manuscript.

Corresponding author

Correspondence to Lauren Waszek.

Ethics declarations

Competing interests

The authors declare no competing interests.

Additional information

Peer review information Nature Geoscience thanks Sidao Ni, Saskia Goes and Johannes Buchen for their contribution to the peer review of this work. Primary Handling editors: Stefan Lachowycz and Simon Harold.

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

Supplementary information

Supplementary information

Supplementary methods, discussion, references, Figs. SI1–SI31 and Table SI1.

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Waszek, L., Tauzin, B., Schmerr, N.C. et al. A poorly mixed mantle transition zone and its thermal state inferred from seismic waves. Nat. Geosci. 14, 949–955 (2021). https://doi.org/10.1038/s41561-021-00850-w

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1038/s41561-021-00850-w

This article is cited by

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