Abstract
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.
This is a preview of subscription content, access via your institution
Relevant articles
Open Access articles citing this article.
-
Upper mantle melt caused by a subducted slab in the Indian-Eurasian continental subduction zone
Communications Earth & Environment Open Access 05 December 2023
-
Insights into magma ocean dynamics from the transport properties of basaltic melt
Nature Communications Open Access 08 December 2022
-
Deep mantle melting, global water circulation and its implications for the stability of the ocean mass
Progress in Earth and Planetary Science Open Access 10 December 2020
Access options
Subscribe to this journal
Receive 12 print issues and online access
$259.00 per year
only $21.58 per issue
Rent or buy this article
Prices vary by article type
from$1.95
to$39.95
Prices may be subject to local taxes which are calculated during checkout



References
Revenaugh, J. & Sipkin, S. Seismic evidence for silicate melt atop the 410-km discontinuity. Nature 369, 474–476 (1994).
Vinnik, L. & Farra, V. Low velocity atop the 410-km discontinuity and mantle plumes. Earth Planet. Sci. Lett. 262, 398–412 (2007).
Bercovici, D. & Karato, S. Whole mantle convection and transition-zone water filter. Nature 425, 39–44 (2003).
Leahy, G. M. & Bercovici, D. On the dynamics of a hydrous melt layer above the transition zone. J. Geophys. Res. 112, B07401 (2007).
Dasgupta, E. & Hirschmann, M. Melting in the Earth’s deep upper mantle caused by carbon dioxide. Nature 440, 659–662 (2006).
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).
Suzuki, A. & Ohtani, E. Density of peridotite melts at high pressure. Phys. Chem. Mineral. 30, 449–456 (2003).
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).
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).
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).
Schaeffer, A. J. & Bostock, M. G. A low-velocity zone atop the transition zone in Northwestern Canada. J. Geophys. Res. 115, B06302 (2010).
Vinnik, L. & Farra, V. Subcratonic low-velocity layer and flood basalts. Geophys. Res. Lett. 29, 1049–1052 (2002).
Vinnik, L., Kumar, M., Kind, R. & Farra, V. Super-deep low velocity layer beneath the Arabian plate. Geophys. Res. Lett. 30, 1415–1418 (2003).
Fee, D. & Dueker, K. Mantle transition zone topography and structure beneath the Yellowstone hotspot. Geophys. Res. Lett. 31, L18603 (2004).
Jasbinsek, J. & Dueker, K. Ubiquitous low-velocity layer atop the 410-km discontinuity in the northern Rocky Mountains. Geochem. Geophys. Geosys. 8, Q10004 (2007).
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).
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).
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).
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).
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).
Kennett, B. L. N. & Engdahl, E. R. Travel times for global earthquake location and phase identification. Geophys. J. Int. 105, 429–465 (1991).
Revenaugh, J. & Jordan, T. Mantle layering from ScS reverberations : 3. The upper mantle. J. Geophys. Res. 96, 19781–19810 (1991).
Rychert, C. A. & Shearer, P. M. A global view of the lithosphere–asthenosphere boundary. Science 324, 495–498 (2009).
Jordan, T. H. Global tectonic regionalization for seismological data analysis. Bull. Seismol. Soc. Am. 71, 1131–1141 (1981).
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).
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).
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).
Hier-Majumder, S., Ricard, Y. & Bercovici, D. Role of grain boundaries in magma migration and storage. Earth Planet. Sci. Lett. 248, 735–749 (2006).
Debayle, E., Kennett, B. & Priestley, K. Global azimuthal seismic anisotropy and the unique plate-motion deformation of Australia. Nature 433, 509–512 (2005).
Efron, B. & Tibshirani, R. Statistical data analysis in the computer age. Science 253, 390–395 (1991).
Acknowledgements
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.
Author information
Authors and Affiliations
Contributions
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.
Corresponding author
Ethics declarations
Competing interests
The authors declare no competing financial interests.
Supplementary information
Supplementary Information
Supplementary Information (PDF 2694 kb)
Rights and permissions
About this article
Cite this article
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). https://doi.org/10.1038/ngeo969
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1038/ngeo969
This article is cited by
-
Upper mantle melt caused by a subducted slab in the Indian-Eurasian continental subduction zone
Communications Earth & Environment (2023)
-
Compositional heterogeneity in the mantle transition zone
Nature Reviews Earth & Environment (2022)
-
Insights into magma ocean dynamics from the transport properties of basaltic melt
Nature Communications (2022)
-
Deep mantle melting, global water circulation and its implications for the stability of the ocean mass
Progress in Earth and Planetary Science (2020)
-
Distinct slab interfaces imaged within the mantle transition zone
Nature Geoscience (2020)