Iron spin transition in Earth's mantle.

Journal article

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.

Authors: Speziale, S; Milner, A; Lee, V; Clark, S; Pasternak, M

• Publication status: Published
• Journal: Proceedings of the National Academy of Sciences of the United States of America
• Volume: 102
• Issue: 50
• Pages: 17918-17922
• Publication date: 2005-12-01
• DOI: 10.1073/pnas.0508919102
• EISSN: 1091-6490
• ISSN: 0027-8424
• Language: English
• Keywords: magnesiowustite; lower mantle; Mossbauer