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| Titel |
Global lower mantle structure from multifrequency P- and Pdiff-wave tomography |
| VerfasserIn |
Kasra Hosseini, Karin Sigloch, Simon Stähler, Martin van Driel, Ludwig Auer, Tarje Nissen-Meyer |
| Konferenz |
EGU General Assembly 2016
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| Medientyp |
Artikel
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| Sprache |
en
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 18 (2016) |
| Datensatznummer |
250124591
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| Publikation (Nr.) |
 EGU/EGU2016-4045.pdf |
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| Zusammenfassung |
| We present a new global seismic tomography model of isotropic P-wave velocity anomalies at all mantle depths. This broadband waveform inversion seamlessly incorporates a very large set of 391,320 core-diffracted P-phase measurements (Pdiff) alongside conventional teleseismic P and PP waveforms. All phases are measured and modelled from 30 s dominant period to the highest frequencies that produce satisfactory fits (~3 s). The few examples of prior tomographies that incorporated Pdiff phases included only a few hundred measurements and not in a broadband, multifrequency framework, such as here.
Pdiff waves extensively sample the lower third of the mantle and the core-mantle boundary. Hence their inclusion in a technically rigorous manner vastly improves spatial resolution of the deepest mantle.
We present our methods and discuss first-order features of the lower-mantle structures thus obtained: geometries of fast velocity anomalies representing the oldest subducted slabs still visible, and the subdivisions of Large Low Shear Velocity Provinces, as imaged by P-waves. |
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