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Iron spin transition in Earth's mantle.

ABSTRACT: High-pressure Mössbauer spectroscopy on several compositions across the (Mg,Fe)O magnesiowüstite solid solution confirms that ferrous iron (Fe(2+)) undergoes a high-spin to low-spin transition at pressures and for compositions relevant to the bulk of the Earth's mantle. High-resolution x-ray diffraction measurements document a volume change of 4-5% across the pressure-induced spin transition, which is thus expected to cause seismological anomalies in the lower mantle. The spin transition can lead to dissociation of Fe-bearing phases such as magnesiowüstite, and it reveals an unexpected richness in mineral properties and phase equilibria for the Earth's deep interior.

SUBMITTER: Speziale S

PROVIDER: S-EPMC1312404 | biostudies-literature | 2005 Dec

REPOSITORIES: biostudies-literature

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Iron spin transition in Earth's mantle.

Speziale S S Milner A A Lee V E VE Clark S M SM Pasternak M P MP Jeanloz R R

Proceedings of the National Academy of Sciences of the United States of America 20051205 50

High-pressure Mössbauer spectroscopy on several compositions across the (Mg,Fe)O magnesiowüstite solid solution confirms that ferrous iron (Fe(2+)) undergoes a high-spin to low-spin transition at pressures and for compositions relevant to the bulk of the Earth's mantle. High-resolution x-ray diffraction measurements document a volume change of 4-5% across the pressure-induced spin transition, which is thus expected to cause seismological anomalies in the lower mantle. The spin transition can lea ...[more]

PMID: 16330758

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