The Melting Curve of Iron to 250 Gigapascals: A Constraint on the Temperature at Earth's Center
Abstract
The melting curve of iron, the primary constituent of Earth's core, has been measured to pressures of 250 gigapascals with a combination of static and dynamic techniques. The melting temperature of iron at the pressure of the core-mantle boundary (136 gigapascals) is 4800 ± 200 K. whereas at the inner core-outer core boundary (330 gigapascals), it is 7600 ± 500 K. Corrected for melting point depression resulting from the presence of impurities, a melting temperature for iron-rich alloy of 6600 K at the inner core-outer core boundary and a maximum temperature of 6900 K at Earth's center are inferred. This latter value is the first experimental upper bound on the temperature at Earth's center, and these results imply that the temperature of the lower mantle is significantly less than that of the outer core.
Additional Information
© 1987 American Association for the Advancement of Science. Received 8 December 1986; accepted 29 January 1987. We are grateful to E. Knittle, D. L. Heinz, D. J. Stevenson, and J. M. Brown for helpful comments and experimental advice. Work supported by NSF and NASA, including grants EAR8313746, EAR8419259, and EAR8508969 to the California Institute of Technology. This is contribution 4425 of the Division of Geological and Planetary Sciences of the California Institute of Technology.Additional details
- Eprint ID
- 51158
- Resolver ID
- CaltechAUTHORS:20141103-090949803
- NASA
- EAR 8313746
- NSF
- EAR 8419259
- NSF
- EAR 8508969
- NSF
- Created
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2014-11-03Created 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
- 4425