TY - JOUR
T1 - Sound velocity of liquid Fe-Ni-S at high pressure
AU - Kawaguchi, Saori I.
AU - Nakajima, Yoichi
AU - Hirose, Kei
AU - Komabayashi, Tetsuya
AU - Ozawa, Haruka
AU - Tateno, Shigehiko
AU - Kuwayama, Yasuhiro
AU - Tsutsui, Satoshi
AU - Baron, Alfred Q. R.
PY - 2017/5/9
Y1 - 2017/5/9
N2 - The sound velocity of liquid Fe47Ni28S25 and Fe63Ni12S25 was measured up to 52 GPa/2480 K in externally-resistance-heated and laser-heated diamond-anvil cells (DACs) using high-resolution inelastic X-ray scattering. From these experimental data, we obtained the elastic parameters of liquid Fe47Ni28S25, KS0 = 96.1 ± 2.7 GPa and KS0’ = 4.00 ± 0.13, where KS0 and KS0’ are the adiabatic bulk modulus and its pressure derivative at 1 bar, when the density is fixed at ρ0 = 5.62 ± 0.09 g/cm3 for 1 bar and 2000 K. With these parameters, the sound velocity and density of liquid Fe47Ni28S25 were calculated to be 8.41 ± 0.17 km/s and 8.93 ± 0.19 to 9.10 ± 0.18 g/cm3, respectively, at the core mantle boundary (CMB) conditions of 135 GPa and 3600 − 4300 K. These values are 9.4 % higher and 17–18 % lower than those of pure Fe respectively. Extrapolation of measurements and comparison with seismological models suggest the presence of 5.8–7.5 wt.% sulfur in the Earth's outer core if it is the only light element.
AB - The sound velocity of liquid Fe47Ni28S25 and Fe63Ni12S25 was measured up to 52 GPa/2480 K in externally-resistance-heated and laser-heated diamond-anvil cells (DACs) using high-resolution inelastic X-ray scattering. From these experimental data, we obtained the elastic parameters of liquid Fe47Ni28S25, KS0 = 96.1 ± 2.7 GPa and KS0’ = 4.00 ± 0.13, where KS0 and KS0’ are the adiabatic bulk modulus and its pressure derivative at 1 bar, when the density is fixed at ρ0 = 5.62 ± 0.09 g/cm3 for 1 bar and 2000 K. With these parameters, the sound velocity and density of liquid Fe47Ni28S25 were calculated to be 8.41 ± 0.17 km/s and 8.93 ± 0.19 to 9.10 ± 0.18 g/cm3, respectively, at the core mantle boundary (CMB) conditions of 135 GPa and 3600 − 4300 K. These values are 9.4 % higher and 17–18 % lower than those of pure Fe respectively. Extrapolation of measurements and comparison with seismological models suggest the presence of 5.8–7.5 wt.% sulfur in the Earth's outer core if it is the only light element.
U2 - 10.1002/2016JB013609
DO - 10.1002/2016JB013609
M3 - Article
SN - 2169-9313
JO - Journal of Geophysical Research. Solid Earth
JF - Journal of Geophysical Research. Solid Earth
ER -