HR: 08:00h
AN: MR21A-01 INVITED     [Abstracts]
TI: Liquid miscibility during the evolution of Earth and planetary cores
AU: * Li, J
EM: jackieli@uiuc.edu
AF: University of Illinois, 245 Natural History Building 1301 West Green Street, Urbana, IL 61801 United States
AU: Chen, B
EM: binchen2@uiuc.edu
AF: University of Illinois, 245 Natural History Building 1301 West Green Street, Urbana, IL 61801 United States
AU: Gao, L
EM: liligao2@uiuc.edu
AF: University of Illinois, 245 Natural History Building 1301 West Green Street, Urbana, IL 61801 United States
AU: Agee, C
EM: agee@unm.edu
AF: University of New Mexico, Institute of Meteoritics Dept. of Earth & Planetary Science, Albuquerque, NM 87131 United States
AB: The core is the largest magma chamber in the Earth. Liquid miscibility, if present in the core-forming alloy system, may influence the extent of chemical equilibrium and the process of physical segregation between the two dominant divisions of the Earth. As the Earth cools, the outer core may enter the miscibility gap and develop new layering. Further differentiation in the core would have direct impact on the structure and dynamics of the planet. Fe-rich core is not unique to the Earth. It is likely to exist in other terrestrial planets and in some major moons of giant planets. In order to evaluate the relevance and understand the role of liquid miscibility during the evolution of the Earth and planetary cores, we have conducted high-pressure experiments on liquid miscibility. A number of candidate core alloy compositions have been studied, including binary Fe-S system, ternary Fe-S-O and Fe-S-C systems, and quaternary Fe-Ni-S-O and Fe-Ni-S-C systems. Experimental conditions range from 2 to 25 GPa, and between 1273 and 2500 K. Based on the new data, we will evaluate 1) if liquid miscibility can provide additional constraints on core compositions; 2) if liquid miscibility existed, exists, or will occur during the evolution of the Earth and planetary cores.
DE: 1015 Composition of the core
DE: 3924 High-pressure behavior
DE: 8124 Earth's interior: composition and state (1212, 7207, 7208, 8105)
DE: 8125 Evolution of the Earth (0325)
DE: 8412 Reactions and phase equilibria (1012, 3612)
SC: Mineral and Rock Physics [MR]
MN: Fall Meeting 2005