Melting behavior of H[subscript 2]O at high pressures and temperatures

Journal Article · Mon Jul 19 04:00:00 EDT 2010 · Geophys. Res. Lett.

DOI:https://doi.org/10.1029/2005GL022499· OSTI ID:1008530

Lin, Jung-Fu; Gregoryanz, Eugene; Struzhkin, Viktor V; Somayazulu, Maddury; Mao, H -K; Hemley, R J ^[1]

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1. CIW

Water plays an important role in the physics and chemistry of planetary interiors. In situ high pressure-temperature Raman spectroscopy and synchrotron x-ray diffraction have been used to examine the phase diagram of H{sub 2}O. A discontinuous change in the melting curve of H{sub 2}O is observed at approximately 35 GPa and 1040 K, indicating a triple point on the melting line. The melting curve of H{sub 2}O increases significantly above the triple point and may intersect the isentropes of Neptune and Uranus. Solid ice could therefore form in stratified layers at depth within these icy planets. The extrapolated melting curve may also intersect with the geotherm of Earth's lower mantle above 60 GPa. The presence of solid H{sub 2}O would result in a jump in the viscosity of the mid-lower mantle and provides an additional explanation for the observed higher viscosity of the mid-lower mantle.

• Research Organization: Advanced Photon Source (APS), Argonne National Laboratory (ANL), Argonne, IL (US)
• Sponsoring Organization: USDOE
• OSTI ID: 1008530
• Journal Information: Geophys. Res. Lett., Journal Name: Geophys. Res. Lett. Journal Issue: (11) ; 2005 Vol. 32; ISSN GPRLAJ; ISSN 0094-8276
• Country of Publication: United States
• Language: ENGLISH

Related Subjects

43 PARTICLE ACCELERATORS
CHEMISTRY
MELTING
PHASE DIAGRAMS
PHYSICS
PLANETS
RAMAN SPECTROSCOPY
SYNCHROTRONS
TRIPLE POINT
VISCOSITY
WATER
X-RAY DIFFRACTION