Publication Date:
2010-04-17
Description:
Hemispherical asymmetry is a prominent feature of Earth's inner core, but how this asymmetry relates to core growth is unknown. Based on multiple-scattering modeling of seismic velocity and attenuation measurements sampling the whole uppermost inner core, we propose that the growth of the solid core implies an eastward drift of the material, driven by crystallization in the Western Hemisphere and melting in the Eastern Hemisphere. This self-sustained translational motion generates an asymmetric distribution of sizes of iron crystals, which grow during their translation. The invoked dynamical process is still active today, which supports the idea of a young inner core.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Monnereau, Marc -- Calvet, Marie -- Margerin, Ludovic -- Souriau, Annie -- New York, N.Y. -- Science. 2010 May 21;328(5981):1014-7. doi: 10.1126/science.1186212. Epub 2010 Apr 15.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Universite de Toulouse-CNRS, Observatoire Midi-Pyrenees, 14 Avenue Edouard Belin, 31400 Toulouse, France. marc.monnereau@dtp.obs-mip.fr〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/20395477" target="_blank"〉PubMed〈/a〉
Print ISSN:
0036-8075
Electronic ISSN:
1095-9203
Topics:
Biology
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Chemistry and Pharmacology
,
Computer Science
,
Medicine
,
Natural Sciences in General
,
Physics
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