HR: 0800h
AN: MR31A-0131 [Abstracts]
TI: Thermal Expansion of Fe3S
AU: * Chen, B
EM: binchen2@uiuc.edu
AF: Department of Geology, University of Illinois at Urbana-Champaign, 245 Natural History Building,
1301 West Green Street, Urbana, IL 61820
United States
AU: Li, J
EM: jackieli@uiuc.edu
AF: Department of Geology, University of Illinois at Urbana-Champaign, 245 Natural History Building,
1301 West Green Street, Urbana, IL 61820
United States
AB:
We have investigated the thermal expansion of the iron-sulfur compound Fe3S at pressures up to 42.5 GPa and temperatures
to 900 K by using synchrotron X-ray diffraction techniques. It has been well recognized that iron and sulfur are possible
elements in the cores of the terrestrial planets. According to our present knowledge, Fe3S is the most iron-rich
compound in the Fe-S system. The Earth's core probably has sulfur content between pure iron and Fe3S. Given higher
sulfur content, Fe3S is a possible component of the Martian inner core. Hence, the equation-of-state of Fe3S is of
fundamental importance for our understanding of the Earth's and planetary cores. The room temperature compression curve of
Fe3S was determined by Fei et al. [1]. To date, no experimental data have been reported on the thermal expansion of
Fe3S. In this study, we report in situ measurements of thermal expansion of Fe3S at high pressure by means of an
externally-heated diamond-anvil cell and the energy-dispersive X-ray diffraction techniques at x17c beamline, the National
Synchrotron Light Source, Brookhaven National Laboratory. The measured thermal expansion for Fe3S can be directly used
for modeling the cores of the terrestrial planets and is important for interpreting current geophysical observations of the
Earth's and planetary cores.
[1]Fei, Y.-W. , Li, J., Bertka, C.M., and Prewitt, C.T. (2000) Structure type and bulk modulus of Fe3S, a new
iron-sulfur compound. American Mineralogist, 85, 1830-1833.
DE: 1015 Composition of the core
DE: 3630 Experimental mineralogy and petrology
DE: 3919 Equations of state
DE: 3924 High-pressure behavior
DE: 3949 Thermal expansivity
SC: Mineral and Rock Physics [MR]
MN: Fall Meeting 2005