FastFind »   Lastname: doi:10.1029/ Year: | Advanced Search  

AGU: Geophysical Research Letters

 

Keywords

  • high pressure
  • schreibersite
  • Fe3P

Index Terms

  • Geochemistry: Composition of the core
  • Mineralogy and Petrology: Planetary mineralogy and petrology
  • Mineral Physics: Equations of state
  • Mineral Physics: High-pressure behavior
  • Mineral Physics: X-ray, neutron, and electron spectroscopy and diffraction

Abstract

Equation of state and high-pressure stability of Fe3P-schreibersite: Implications for phosphorus storage in planetary cores

Henry P. Scott

Department of Physics and Astronomy, Indiana University, South Bend, Indiana, USA

Sabrina Huggins

Department of Physics and Astronomy, Indiana University, South Bend, Indiana, USA

Mark R. Frank

Department of Geology and Environmental Geosciences, Northern Illinois University, Dekalb, Illinois, USA

Steven J. Maglio

Department of Geology and Environmental Geosciences, Northern Illinois University, Dekalb, Illinois, USA

C. David Martin

Department of Geological Sciences, State University of New York at Stony Brook, New York, USA

Yue Meng

High Pressure Collaborative Access Team, Carnegie Institution of Washington, Argonne, Illinois, USA

Javier Santillán

Department of Earth Sciences, Massachusetts Institute of Technology, Cambridge, Massachusetts, USA

Quentin Williams

Department of Earth Sciences, University of California, Santa Cruz, California, USA

We have collected in situ X-ray diffraction patterns of end-member Fe3P-schreibersite in a diamond anvil cell to pressures of 30 GPa at 300 K. Some samples of Fe3P were also laser heated at high pressure to temperatures of ∼2000 K and examined following thermal quench. Below 8 GPa, variation of the schreibersite unit cell delineates a smooth pressure-volume curve corresponding to a second order Birch-Murnaghan equation of state with bulk modulus, K0T , of 159(1) GPa. Above 8 GPa, however, the schreibersite structure shows substantial stiffening, and an unidentified structure develops between 17 and 30 GPa; upon decompression to ambient pressure the schreibersite structure returns. Therefore, although ubiquitous in iron-rich meteorites, it is unlikely that schreibersite is the stable phosphorus-bearing phase in deep planetary cores.

Received 26 December 2006; accepted 14 February 2007; published 21 March 2007.

Citation: Scott, H. P., S. Huggins, M. R. Frank, S. J. Maglio, C. D. Martin, Y. Meng, J. Santillán, and Q. Williams (2007), Equation of state and high-pressure stability of Fe3P-schreibersite: Implications for phosphorus storage in planetary cores, Geophys. Res. Lett., 34, L06302, doi:10.1029/2006GL029160.

Cited By

Please wait one moment ...