HR: 0800h
AN: DI31A-0257    [Abstracts]
TI: Effect of pressure on the melting behavior of the Fe-S system at moderate pressures: Insight into the state of Mercury's core
AU: * Chen, B
EM: binchen2@uiuc.edu
AF: U. of Illinois, Urbana-Champaign, 1301 W. Green Street, Urbana, IL 61801, United States
AU: Li, J
EM: jackieli@uiuc.edu
AF: U. of Illinois, Urbana-Champaign, 1301 W. Green Street, Urbana, IL 61801, United States
AU: Hauck, S A
EM: hauck@case.edu
AF: Case Western Reserve University, 10900 Euclid Avenue, Cleveland, OH 44106, United States
AB: The effect of pressure on the liquidus curve of the iron-rich portion of the Fe-S system has been investigated using a multi-anvil apparatus. At 1 bar, the liquidus curve has two inflection points, indicating a positive deviation from the ideal liquidus curve. The curve gradually straightens out with increasing pressure. Our data show that at 10 GPa the curve is consistent with ideal solution behavior. However, the positive deviation returns at 14 GPa, leading to a significant drop in the liquidus temperature at relatively low sulfur conent. The observed pressure effect on the melting behavior of the Fe-S system allows us to establish a link between the current physical state and sulfur content of Mercury's core, and to investigate the history of solid iron precipitation in Mercury.
DE: 1507 Core processes (1213, 8115)
DE: 1510 Dynamo: theories and simulations
DE: 3612 Reactions and phase equilibria (1012, 8412)
DE: 3924 High-pressure behavior
DE: 7207 Core (1212, 1213, 8124)
SC: Study of the Earth's Deep Interior [DI]
MN: 2007 Fall Meeting