Physics
Scientific paper
Jan 2005
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2005pepi..148...73n&link_type=abstract
Physics of the Earth and Planetary Interiors, Volume 148, Issue 1, p. 73-84.
Physics
4
Scientific paper
In situ synchrotron X-ray diffraction experiments were conducted using the SPEED-1500 multi-anvil press at SPring-8 on majoritic garnet synthesized from natural mid-ocean ridge basalt (MORB), whose chemical composition is close to the average of oceanic crust, at 19 GPa and 2200 K. Pressure volume temperature data were collected using a newly developed high-pressure cell assembly to 21 GPa and 1273 K. Data were fit to the high-temperature Birch-Murnaghan equation of state, with fixed values for the ambient cell volume (V0 = 1574.14(4) Å3) and the pressure derivative of the isothermal bulk modulus (KT = 4). This yielded an isothermal bulk modulus of KT0 = 173(1) GPa, a temperature derivative of the bulk modulus (∂KT/∂T)P = -0.022(5) GPa K-1, and a volumetric coefficient of thermal expansivity α = a + bT with values of a = 2.0(3) × 10-5 K-1 and b = 1.0(5) × 10-8 K-2. The derived thermoelastic parameters are very similar to those of pyrope. The density of subducted oceanic crust compared to pyrolitic mantle at the conditions in Earth's transition zone (410 660 km depth) was calculated using these results and previously reported thermoelastic parameters for MORB and pyrolite mineral assembledges. These calculations show that oceanic crust is denser than pyrolitic mantle throughout the mantle transition zone along a normal geotherm, and the density difference is insensitive to temperature at the pressures in lower part of the transition zone.
Aoki Ichiro
Funakoshi Ken-Ichi
Matsukage Kyoko N.
Nishihara Yu
Takahashi Eiichi
No associations
LandOfFree
Thermal equation of state of majorite with MORB composition does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Thermal equation of state of majorite with MORB composition, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Thermal equation of state of majorite with MORB composition will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-1065287