HR: 09:09h
AN: MR41A-06    [Abstracts]
TI: Experimental constraints on silicon in the Earth's core
AU: * Li, J
EM: jackieli@uiuc.edu
AF: University of Illinois, Dept. Geology 245 NHB, 1301 W. Green St., Urbana, IL 61801 United States
AU: van Westrenen, W
EM: willem.vanwestrenen@erdw.ethz.ch
AF: ETH-Zurich, Sonneggstrasse 5, Zurich, CH 8092 Switzerland
AU: Komabayashi, T
EM: tkomabay@geo.titech.ac.jp
AF: Tokyo Institute of Technology, Dept of Earth & Planetary Sciences, Tokyo, IL 60637 Japan
AU: Hellwig, H
EM: hhellwig@uiuc.edu
AF: University of Illinois, Dept. Geology 245 NHB, 1301 W. Green St., Urbana, IL 61801 United States
AU: Van Orman, J
EM: jav12@cwru.edu
AF: Case Western Reserve University, Dept Geological Sciences Rm A W Smith 112, Cleveland, OH 44106 United States
AU: Fei, Y
EM: y.fei@gl.ciw.edu
AF: Carnegie Institution of Washington Carnegie Institution of Washington, The Geophysical Laboratory 5251 Broad Branch Rd. NW, Washington, DC 20015 United States
AU: Minarik, W
EM: minarik@eps.mcgill.ca
AF: McGill University, Dept Earth and Planetary Sciences 3450 University St, Montreal, Que H3A 2A7 Canada
AU: Funakoshi, K
EM: funakosi@spring8.or.jp
AF: Japan Synchrotron Radiation Research Institute, SPring-8, Hyogo, 679-5198 Japan
AB: The light element composition of the core is fundamental to our understanding of the nature and dynamics of the Earth but is poorly constrained. One of the criteria for the principal light element in the core is that its partitioning between the inner core and outer core must reproduce the observed density contrast at the inner core boundary (ICB). To apply this criterion, we need to know the melting relations in the candidate Fe-light-element systems. Presently, experimental data on high pressure melting behavior of Fe-alloy systems are scarce. We have determined the melting relations in the Fe-Si binary system to 27 GPa, using in situ x-ray diffraction and x-ray radiograph techniques at BL04B1 beamline, SPring-8. Recovered samples have been analyzed using an electron probe microanalyzer at the Geophysical Laboratory, Carnegie Institution of Washington. Combining the structural data from x-ray diffraction and compositional data from electron probe analysis allows us to reevaluate the proposal of silicon as the major light element in the Earth's core.
DE: 3630 Experimental mineralogy and petrology
DE: 3924 High-pressure behavior
DE: 3954 X ray, neutron, and electron spectroscopy and diffraction
DE: 1507 Core processes (8115)
DE: 1015 Composition of the core
SC: Mineral and Rock Physics [MR]
MN: 2004 AGU Fall Meeting