Candy Wrapper for the Earth's Inner Core
2013 (English)In: Scientific Reports, ISSN 2045-2322, Vol. 3, 2096- p.Article in journal (Refereed) Published
Recent global expansion of seismic data motivated a number of seismological studies of the Earth's inner core that proposed the existence of increasingly complex structure and anisotropy. In the meantime, new hypotheses of dynamic mechanisms have been put forward to interpret seismological results. Here, the nature of hemispherical dichotomy and anisotropy is re-investigated by bridging the observations of PKP(bc-df) differential travel-times with the iron bcc/hcp elastic properties computed from first-principles methods. The Candy Wrapper velocity model introduced here accounts for a dynamic picture of the inner core (i.e., the eastward drift of material), where different iron crystal shapes can be stabilized at the two hemispheres. We show that seismological data are best explained by a rather complicated, mosaic-like, structure of the inner core, where well-separated patches of different iron crystals compose the anisotropic western hemispherical region, and a conglomerate of almost indistinguishable iron phases builds-up the weakly anisotropic eastern side.
Place, publisher, year, edition, pages
Nature Publishing Group, 2013. Vol. 3, 2096- p.
Travel-Times, Elastic-Anisotropy, Seismic Velocity, Ab-Initio, Iron, Pressure, Constraints, Attenuation, Heterogeneity, Temperature
Engineering and Technology
IdentifiersURN: urn:nbn:se:kth:diva-124971DOI: 10.1038/srep02096ISI: 000321036900009ScopusID: 2-s2.0-84899824553OAI: oai:DiVA.org:kth-124971DiVA: diva2:638932
FunderSwedish Research Council, 2012-4379 2010-3187
QC 201308052013-08-052013-08-022013-08-05Bibliographically approved