Iron isotopic fractionation between silicate mantle and metallic core at high pressure.
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ABSTRACT:
SUBMITTER: Liu J
PROVIDER: S-EPMC5321738 | biostudies-literature | 2017 Feb
REPOSITORIES: biostudies-literature
Publications
Iron isotopic fractionation between silicate mantle and metallic core at high pressure.
Liu Jin J Dauphas Nicolas N Roskosz Mathieu M Hu Michael Y MY Yang Hong H Bi Wenli W Zhao Jiyong J Alp Esen E EE Hu Justin Y JY Lin Jung-Fu JF
Nature communications 20170220
The +0.1‰ elevated <sup>56</sup>Fe/<sup>54</sup>Fe ratio of terrestrial basalts relative to chondrites was proposed to be a fingerprint of core-mantle segregation. However, the extent of iron isotopic fractionation between molten metal and silicate under high pressure-temperature conditions is poorly known. Here we show that iron forms chemical bonds of similar strengths in basaltic glasses and iron-rich alloys, even at high pressure. From the measured mean force constants of iron bonds, we calc ...[more]
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