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Seismic evidence for a global low-velocity layer within the Earth’s upper mantle


Within the upper mantle, the seismic discontinuity at 410-km depth marks the top of the transition zone and is attributed to pressure-induced transformation of olivine into wadsleyite mineral assemblage. Just above the 410-km discontinuity, a layer characterized by low seismic wave velocities has been identified regionally1,2. This low velocity layer shows poor lateral continuity and is thought to represent partial melting induced by local effects, such as the dehydration of subducted crust1 or the dehydration of water-bearing silicates beneath continental platforms in association with mantle plumes2. However, some models predict that the low-velocity layer should extend globally, because the weaker water storage capacity of upper mantle minerals should induce partial melting of water-bearing silicates throughout this region3,4. Here we report seismic observations from 89 stations worldwide that indicate a thick, intermittent low-velocity layer is located near 350 km depth in the mantle. The low velocity layer is not limited to regions associated with subduction or mantle plumes, and shows no affinity to a particular tectonic environment. We suggest that our data image the thickest parts of a more continuous global structure that shows steep lateral variations in thickness. The presence of a global layer of partial melt above the 410-km discontinuity would modify material circulation in the Earth mantle and may help to reconcile geophysical and geochemical observations3.

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Figure 1: Signal associated with the mantle structure under individual seismic stations.
Figure 2: Modelling the low velocity layer.
Figure 3: Mapping the layer atop the 410-km discontinuity.


  1. Revenaugh, J. & Sipkin, S. Seismic evidence for silicate melt atop the 410-km discontinuity. Nature 369, 474–476 (1994).

    Article  Google Scholar 

  2. Vinnik, L. & Farra, V. Low velocity atop the 410-km discontinuity and mantle plumes. Earth Planet. Sci. Lett. 262, 398–412 (2007).

    Article  Google Scholar 

  3. Bercovici, D. & Karato, S. Whole mantle convection and transition-zone water filter. Nature 425, 39–44 (2003).

    Article  Google Scholar 

  4. Leahy, G. M. & Bercovici, D. On the dynamics of a hydrous melt layer above the transition zone. J. Geophys. Res. 112, B07401 (2007).

    Article  Google Scholar 

  5. Dasgupta, E. & Hirschmann, M. Melting in the Earth’s deep upper mantle caused by carbon dioxide. Nature 440, 659–662 (2006).

    Article  Google Scholar 

  6. Wang, W. & Takahashi, E. Subsolidus and melting experiments of K-doped peridotite KLB-1 to 27 GPa: Its geophysical and geochemical implications. J. Geophys. Res. 105, 2855–2868 (2000).

    Article  Google Scholar 

  7. Suzuki, A. & Ohtani, E. Density of peridotite melts at high pressure. Phys. Chem. Mineral. 30, 449–456 (2003).

    Article  Google Scholar 

  8. Matsukage, K., Jing, Z. & Karato, S. Density of Hydrous silicate melt at the condition of Earth’s deep upper mantle. Nature 438, 488–491 (2005).

    Article  Google Scholar 

  9. Song, T., Helmberger, D. & Grand, S. Low-velocity zone atop the 410-km seismic discontinuity in the northwestern United States. Nature 427, 530–533 (2004).

    Article  Google Scholar 

  10. Vinnik, L., Ren, Y., Stutzmann, E., Farra, V. & Kiselev, S. Observations of S410p and S350p at seismograph stations in California. J. Geophys. Res. 115, B05303 (2010).

    Article  Google Scholar 

  11. Schaeffer, A. J. & Bostock, M. G. A low-velocity zone atop the transition zone in Northwestern Canada. J. Geophys. Res. 115, B06302 (2010).

    Article  Google Scholar 

  12. Vinnik, L. & Farra, V. Subcratonic low-velocity layer and flood basalts. Geophys. Res. Lett. 29, 1049–1052 (2002).

    Article  Google Scholar 

  13. Vinnik, L., Kumar, M., Kind, R. & Farra, V. Super-deep low velocity layer beneath the Arabian plate. Geophys. Res. Lett. 30, 1415–1418 (2003).

    Google Scholar 

  14. Fee, D. & Dueker, K. Mantle transition zone topography and structure beneath the Yellowstone hotspot. Geophys. Res. Lett. 31, L18603 (2004).

    Article  Google Scholar 

  15. Jasbinsek, J. & Dueker, K. Ubiquitous low-velocity layer atop the 410-km discontinuity in the northern Rocky Mountains. Geochem. Geophys. Geosys. 8, Q10004 (2007).

    Article  Google Scholar 

  16. Wittlinger, G. & Farra, V. Converted waves reveal a thick and layered tectosphere beneath the Kalahari super-craton. Earth Planet. Sci. Lett. 254, 404–415 (2007).

    Article  Google Scholar 

  17. Bagley, B., Courtier, A. & Revenaugh, J. Melting in the deep upper mantle oceanward of the Honshu slab. Phys. Earth Planet. Inter. 175, 137–144 (2009).

    Article  Google Scholar 

  18. Gao, W., Matzel, E. & Grand, S. Upper mantle structure beneath eastern Mexico determined from P and S waveform inversion and its implications. J. Geophys. Res. 111, B08307 (2006).

    Google Scholar 

  19. Obayashi, M., Sugioka, H., Yoshimitsu, J. & Fukao, Y. High temperature anomalies oceanward of subducting slabs at the 410-km discontinuity. Earth Planet. Sci. Lett. 239, 9–17 (2006).

    Google Scholar 

  20. Tauzin, B., Debayle, E. & Wittlinger, G. The mantle transition zone as seen by global Pds phases: No clear evidence for a thin transition zone beneath hotspots. J. Geophys. Res. 113, B08309 (2008).

    Article  Google Scholar 

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

    Article  Google Scholar 

  22. Revenaugh, J. & Jordan, T. Mantle layering from ScS reverberations : 3. The upper mantle. J. Geophys. Res. 96, 19781–19810 (1991).

    Article  Google Scholar 

  23. Rychert, C. A. & Shearer, P. M. A global view of the lithosphere–asthenosphere boundary. Science 324, 495–498 (2009).

    Article  Google Scholar 

  24. Jordan, T. H. Global tectonic regionalization for seismological data analysis. Bull. Seismol. Soc. Am. 71, 1131–1141 (1981).

    Google Scholar 

  25. Kohlstedt, D., Keppler, H. & Rubie, D. Solubility of water in the α, β and γ phases of (Mg,Fe)2SiO4 . Contrib. Mineral. Petrol. 123, 345–357 (1996).

    Article  Google Scholar 

  26. Demouchy, S., Deloule, E., Frost, D. & Keppler, H. Pressure and temperature-dependence of water solubility in iron-free wadsleyite. Am. Mineral. 90, 1048–1091 (2005).

    Google Scholar 

  27. Blackman, D. K. & Kendall, J. M. Sensitivity of teleseismic body waves to mineral texture and melt in the mantle beneath a mid-ocean ridge. Phil. Trans. R. Soc. Lond. 355, 217–231 (1997).

    Article  Google Scholar 

  28. Hier-Majumder, S., Ricard, Y. & Bercovici, D. Role of grain boundaries in magma migration and storage. Earth Planet. Sci. Lett. 248, 735–749 (2006).

    Article  Google Scholar 

  29. Debayle, E., Kennett, B. & Priestley, K. Global azimuthal seismic anisotropy and the unique plate-motion deformation of Australia. Nature 433, 509–512 (2005).

    Article  Google Scholar 

  30. Efron, B. & Tibshirani, R. Statistical data analysis in the computer age. Science 253, 390–395 (1991).

    Article  Google Scholar 

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Comments by David Bercovici, S-i. Karato, J. Trampert and Y. Ricard were very helpful to improve the first drafts of this manuscript. This work was supported by the French Young Researcher ANR TOMOGLOB no ANR-06-JCJC-0060 and the Dutch National Science Foundation under grant number NWO:VICI865.03.007. Computational resources were provided by the Netherlands Research Center for Integrated Solid Earth Science (ISES 3.2.5 High End Scientific Computation Resources) and the Institut de Physique du Globe de Strasbourg through the Beowolf computational resources. We thank the Iris and Geoscope data centres for providing seismological data.

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B.T. designed the study and the numerical experiments, conducted the numerical experiments and the analysis of the seismic data and wrote the manuscript. E.D. contributed to the design of the numerical experiment and to the interpretation of the results and wrote the manuscript. G.W. developed some tools necessary to process the data and contributed to the design of the numerical experiment, the interpretation of the results and the preparation of the manuscript.

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Correspondence to Benoît Tauzin.

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Tauzin, B., Debayle, E. & Wittlinger, G. Seismic evidence for a global low-velocity layer within the Earth’s upper mantle. Nature Geosci 3, 718–721 (2010).

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