IDEAS home Printed from https://ideas.repec.org/a/nat/nature/v391y1998i6668d10.1038_35601.html
   My bibliography  Save this article

Evidence for partial melt at the core–mantle boundary north of Tonga from the strong scattering of seismic waves

Author

Listed:
  • John E. Vidale

    (University of California, Los Angeles)

  • Michael A. H. Hedlin

    (University of California, San Diego)

Abstract

Scattered waves that precede the seismic phase PKP (which traverses the Earth's core) have been used to identify and locate small-scale heterogeneity in the Earth's mantle1,2,3,4,5,6. A recent study has demonstrated that the global data set of these precursors is consistent with weak heterogeneity (about 1 per cent r.m.s. velocity variation) distributed throughout the mantle7. Here we show, however, that anomalously large PKP precursors from earthquakes in northern Tonga require much stronger heterogeneity (10–15 per cent r.m.s. velocity variation) in a layer about 60 km thick near the core–mantle boundary below Tonga. This region of the core–mantle boundary is also marked by low shear-wave velocities in the lower mantle8 and is near an area of very low compressional-wave velocity in the lowermost tens of kilometres of the mantle9, which has been interpreted as evidence for the presence of partial melt10. The strength of thescattering that we observe provides strong support for the presence of partial melt in this area, and also suggests that vigorous small-scale convection is taking place at the core–mantle boundary.

Suggested Citation

  • John E. Vidale & Michael A. H. Hedlin, 1998. "Evidence for partial melt at the core–mantle boundary north of Tonga from the strong scattering of seismic waves," Nature, Nature, vol. 391(6668), pages 682-685, February.
    • Handle: RePEc:nat:nature:v:391:y:1998:i:6668:d:10.1038_35601
    DOI: 10.1038/35601
    as

    Download full text from publisher

    File URL: https://www.nature.com/articles/35601
    File Function: Abstract
    Download Restriction: Access to the full text of the articles in this series is restricted.
    File URL: https://libkey.io/10.1038/35601?utm_source=ideas
    LibKey link: if access is restricted and if your library uses this service, LibKey will redirect you to where you can use your library subscription to access this item
    ---><---

    As the access to this document is restricted, you may want to search for a different version of it.

    More about this item

    Statistics

    Access and download statistics

    Corrections

    All material on this site has been provided by the respective publishers and authors. You can help correct errors and omissions. When requesting a correction, please mention this item's handle: RePEc:nat:nature:v:391:y:1998:i:6668:d:10.1038_35601. See general information about how to correct material in RePEc.

    If you have authored this item and are not yet registered with RePEc, we encourage you to do it here. This allows to link your profile to this item. It also allows you to accept potential citations to this item that we are uncertain about.

    We have no bibliographic references for this item. You can help adding them by using this form .

    If you know of missing items citing this one, you can help us creating those links by adding the relevant references in the same way as above, for each refering item. If you are a registered author of this item, you may also want to check the "citations" tab in your RePEc Author Service profile, as there may be some citations waiting for confirmation.

    For technical questions regarding this item, or to correct its authors, title, abstract, bibliographic or download information, contact: Sonal Shukla or Springer Nature Abstracting and Indexing (email available below). General contact details of provider: http://www.nature.com .

    Please note that corrections may take a couple of weeks to filter through the various RePEc services.

    IDEAS is a RePEc service. RePEc uses bibliographic data supplied by the respective publishers.