Publication Date:
2010-09-18
Description:
Interrogating physical processes that occur within the lowermost mantle is a key to understanding Earth's evolution and present-day inner composition. Among such processes, partial melting has been proposed to explain mantle regions with ultralow seismic velocities near the core-mantle boundary, but experimental validation at the appropriate temperature and pressure regimes remains challenging. Using laser-heated diamond anvil cells, we constructed the solidus curve of a natural fertile peridotite between 36 and 140 gigapascals. Melting at core-mantle boundary pressures occurs at 4180 +/- 150 kelvin, which is a value that matches estimated mantle geotherms. Molten regions may therefore exist at the base of the present-day mantle. Melting phase relations and element partitioning data also show that these liquids could host many incompatible elements at the base of the mantle.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Fiquet, G -- Auzende, A L -- Siebert, J -- Corgne, A -- Bureau, H -- Ozawa, H -- Garbarino, G -- New York, N.Y. -- Science. 2010 Sep 17;329(5998):1516-8. doi: 10.1126/science.1192448.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Institut de Mineralogie et de Physique des Milieux Condenses, Institut de Physique du Globe de Paris, Universite Pierre et Marie Curie, UMR CNRS 7590, Universite Paris Diderot, 140 rue de Lourmel, 75015 Paris, France. guillame.fiquet@impmc.upmc.fr〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/20847269" 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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