Phase diagram of iron, revised-core temperatures
Abstract
Shock-wave experiments on iron preheated to 1573 K from 14 to 73 GPa, yield sound velocities of the γ- and liquid-phases. Melting is observed in the highest pressure (∼71 ± 2 GPa) experiments at calculated shock temperatures of 2775 ± 160 K. This single crossing of the γ-liquid boundary agrees with the γ-iron melting line of Boehler [1993], Saxena et al. [1993], and Jephcoat and Besedin [1997]. This γ-iron melting curve is ∼300°C lower than that of Shen et al. [1998] at 80 GPa. In agreement with Brown [2001] the discrepancy between the diamond cell melting data and the iron shock temperatures require the occurrence of yet another sub-solidus phase along the principal Hugoniot at ∼200 GPa. This would reconcile the static and dynamic data for iron's melting curve. Upward pressure and temperature extrapolation of the γ-iron melting curve to 330 GPa yields 5300 ± 400 K for the inner core-outer core boundary temperature.
Additional Information
© 2002 by the American Geophysical Union. Received 7 November 2001; accepted 6 December 2001; published 13 April 2002. Research supported by NSF. We thank T. S. Duffy for a preprint, and E. Gelle and M. Long for technical assistance. The helpful comments of reviewers R. Boehler and S. Saxena, as well as a third reviewer of a revised version are greatly appreciated. Contribution #8576, Division of Geological and Planetary Sciences.Attached Files
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Additional details
- Eprint ID
- 50680
- Resolver ID
- CaltechAUTHORS:20141022-110225653
- NSF
- Created
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2014-10-22Created from EPrint's datestamp field
- Updated
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2021-11-10Created from EPrint's last_modified field
- Other Numbering System Name
- Caltech Division of Geological and Planetary Sciences
- Other Numbering System Identifier
- 8576