Attenuation tomography of the upper inner core

Date

2017

Authors

Pejic, Tanja
Tkalčić, Hrvoje
Sambridge, Malcolm
Cormier, Vernon F.
Benavente, Roberto

Journal Title

Journal ISSN

Volume Title

Publisher

Wiley Blackwell

Abstract

The solidification of the Earth's inner core shapes its texture and rheology, affecting the attenuation and scattering of seismic body waves transmitted through it. Applying attenuation tomography in a Bayesian framework to 398 high-quality PKIKP waveforms, we invert for the apparent Qp for the uppermost 400 km below the inner core boundary at latitudes 45°S to 45°N. We use damping and smoothing for regularization of the inversion, and it seems that the smoothing regularization combined with the discrepancy principle works better for this particular problem of attenuation tomography. The results are consistent with a regional variation in inner core attenuation more complex than hemispherical, suggesting coupling between inner core solidification and the thermal structure of the lowermost mantle

Description

Keywords

Citation

Source

Journal of Geophysical Research: Solid Earth

Type

Journal article

Book Title

Entity type

Access Statement

Open Access

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Restricted until