Phonon Density of States and Sound Velocities of Magnesiow?stite in Earth's Lower Mantle

Journal Article · Fri Jan 20 04:00:00 EST 2006 · Geophysical Research Letters, vol. 33, N/A, November 18, 2006, L22304

OSTI ID:898494

Lin, J; Jacosben, S D; Sturhahn, W; Jackson, J; Zhao, J; Yoo, C

The partial phonon densities of states of iron in magnesiowuestite [(Mg{sub 0.75},Fe{sub 0.25})O] have been measured by nuclear inelastic X-ray scattering up to 109 GPa. Compressional and shear wave velocities, shear moduli, and their pressure derivatives increase significantly across the spin-pairing transition of iron in (Mg{sub 0.75},Fe{sub 0.25})O at approximately 50 GPa. The effects of the transition on the elastic properties of (Mg,Fe)O at lower-mantle pressures are in contrast to what was predicted by studying MgO and high-spin magnesiowuestite, and need to be considered in future geophysical modeling of the lower mantle. The transition also affects other thermodynamic properties of magnesiowuestite under high pressures.

• Research Organization: Lawrence Livermore National Laboratory (LLNL), Livermore, CA
• Sponsoring Organization: USDOE
• DOE Contract Number: W-7405-ENG-48
• OSTI ID: 898494
• Report Number(s): UCRL-JRNL-218397
• Journal Information: Geophysical Research Letters, vol. 33, N/A, November 18, 2006, L22304, Journal Name: Geophysical Research Letters, vol. 33, N/A, November 18, 2006, L22304
• Country of Publication: United States
• Language: English

Related Subjects

58 GEOSCIENCES
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
ELASTICITY
IRON
PHONONS
SCATTERING
SHEAR
SIMULATION
THERMODYNAMIC PROPERTIES