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Journal Articles

X-ray and neutron study on the structure of hydrous SiO$$_{2}$$ glass up to 10 GPa

Urakawa, Satoru*; Inoue, Toru*; Hattori, Takanori; Sano, Asami; Kohara, Shinji*; Wakabayashi, Daisuke*; Sato, Tomoko*; Funamori, Nobumasa*; Funakoshi, Kenichi*

Minerals (Internet), 10(1), p.84_1 - 84_13, 2020/01

 Times Cited Count:4 Percentile:72.56(Geochemistry & Geophysics)

The structure of hydrous amorphous SiO$$_{2}$$ is fundamental to investigate the effects of water on the physicochemical properties of oxide glasses and magma. The hydrous SiO$$_{2}$$ glass with 13 wt.% D$$_{2}$$O was synthesized under high-pressure and high-temperature conditions and its structure was investigated by small angle X-ray scattering, X-ray diffraction, and neutron diffraction experiments at pressures of up to 10 GPa and room temperature. This hydrous glass is separated into a SiO$$_{2}$$ rich major phase and a D$$_{2}$$O rich minor phase. Medium-range order of the hydrous glass shrinks compared to the anhydrous SiO$$_{2}$$ glass due to disruption of SiO$$_{4}$$ linkage by formation of Si-OD deuterioxyl, while the pressure response is similar. Most of D$$_{2}$$O molecules are in the small domains and hardly penetrate into SiO$$_{2}$$ major phase.

Journal Articles

Ponded melt at the boundary between the lithosphere and asthenosphere

Sakamaki, Tatsuya*; Suzuki, Akio*; Otani, Eiji*; Terasaki, Hidenori*; Urakawa, Satoru*; Katayama, Yoshinori; Funakoshi, Kenichi*; Wang, Y.*; Hernlund, J. W.*; Ballmer, M. D.*

Nature Geoscience, 6(12), p.1041 - 1044, 2013/12

 Times Cited Count:107 Percentile:97.17(Geosciences, Multidisciplinary)

The bounday between Earth's rigid lighosphere and the underlying, ductile ashenosphere is marked by a distinct siseismic discontinuity. We measure the density, viscosity and structure of basaltic magmas using high-pressure and high-temperature experiments and in situ X-ray analysis under pressure of up to 5.5 GPa. We find that the magmas rapidly become denser with increasing presure and show a viscosity minimum near 4 GPa. Magma mobility determined by the density and viscosity data exhibits a peak at pressures corresponding to depths of 120-150 km, within the asthenosphere. The diminishing mobility of magma in Earth's asthenosphere as the mlets ascend could lead to excessive melt accumulation at depths of 80-100 km, at the lithosphere-asthenosphere boundary. It is concluded that the observed seismic discontinuity at the lithosphere-asthenosphere boundary records this accumulation of melt.

Journal Articles

Density measurement of liquid FeS at high pressures using synchrotron X-ray absorption

Nishida, Keisuke*; Otani, Eiji*; Urakawa, Satoru*; Suzuki, Akio*; Sakamaki, Tatsuya*; Terasaki, Hidenori*; Katayama, Yoshinori

American Mineralogist, 96(5-6), p.864 - 868, 2011/05

 Times Cited Count:29 Percentile:72.72(Geochemistry & Geophysics)

The density of liquid iron sulfide (FeS) was measured up to 3.8 GPa and 1800 K using the X-ray absorption method. The compression curve of the liquid FeS can be fitted using the Vinet equation of state. Isothermal bulk modulus and its temperature and pressure derivatives were determined by a non-linear least squares fit. Liquid FeS is more compressible than Fe-rich Fe-S liquid.

Journal Articles

Density of carbonated peridotite magma at high pressure using an X-ray absorption method

Sakamaki, Tatsuya*; Otani, Eiji*; Urakawa, Satoru*; Terasaki, Hidenori*; Katayama, Yoshinori

American Mineralogist, 96(4), p.553 - 557, 2011/04

 Times Cited Count:28 Percentile:70.17(Geochemistry & Geophysics)

The density of carbonated peridotite magma was measured up to 3.8 GPa and 2100 K using an X-ray absorption method. The bulk modulus of carbonated peridotite magma is larger than that of hydrous peridotite magma. The partial molar volume of CO$$_{2}$$ in magma under high pressure and temperature conditions was calculated. Our results show that the partial molar volume of CO$$_{2}$$ is less compressible than that of H$$_{2}$$O, suggesting that, on an equal molar basis, CO$$_{2}$$ is more effective than H$$_{2}$$O in reducing peridotite melt density at high pressure.

Journal Articles

Density of high-Ti basalt magma at high pressure and origin of heterogeneities in the lunar mantle

Sakamaki, Tatsuya*; Otani, Eiji*; Urakawa, Satoru*; Suzuki, Akio*; Katayama, Yoshinori; Zhao, D.*

Earth and Planetary Science Letters, 299(3-4), p.285 - 289, 2010/11

 Times Cited Count:23 Percentile:56.93(Geochemistry & Geophysics)

The density of the Apollo 14 black glass melt, which has the highest TiO$$_{2}$$ content of pristine mare glasses, was measured to 4.8 GPa and 2100 K using an X-ray absorption method. A fit of the pressure-density-temperature data to the high-temperature Birch-Murnaghan equation of state yielded the isothermal bulk modulus, its pressure derivative, and the temperature derivative of the bulk modulus. Implication for heterogeneities in the lunar mantle is discussed.

Journal Articles

Density of dry peridotite magma at high pressure using an X-ray absorption method

Sakamaki, Tatsuya*; Otani, Eiji*; Urakawa, Satoru*; Suzuki, Akio*; Katayama, Yoshinori

American Mineralogist, 95(1), p.144 - 147, 2010/01

 Times Cited Count:31 Percentile:69.91(Geochemistry & Geophysics)

The density of a peridotite magma was measured up to 2.5 GPa and 2300 K using an X-ray absorption method. The method allowed measurement of the density of a peridotite melt under seven different conditions and clarified the pressure and temperature dependence of the density. A fit of the pressure-density-temperature data to the high-temperature Birch-Murnaghan equation of state yielded the isothermal bulk modulus, $$K_{T0} = 24.0 pm 1.3$$ GPa, its pressure derivative, $$K'_{0} = 7.3 pm 0.8$$, and the derivative of bulk modulus $$(delta K_{T}/delta T)_{P} = -0.0027 pm 0.0017$$ GPa/K at 2100 K. The large bulk modulus and its pressure derivative of the peridotite melt compared with that of basaltic melt is consistent with previous results from sink-float experiments.

Journal Articles

Measurement of hydrous peridotite magma density at high pressure using the X-ray absorption method

Sakamaki, Tatsuya*; Otani, Eiji*; Urakawa, Satoru*; Suzuki, Akio*; Katayama, Yoshinori

Earth and Planetary Science Letters, 287(3-4), p.293 - 297, 2009/10

 Times Cited Count:47 Percentile:77.4(Geochemistry & Geophysics)

The density of hydrous peridotite magma containing 5wt.% H$$_{2}$$O was measured at pressures and temperatures up to 4.3 GPa and 2073 K, respectively, using the X-ray absorption method. A fit of pressure-density-temperature data to the high-temperature Birch-Murnagan equation of state yields isothermal bulk modulus $$K_{T}=8.8pm 1.9$$ GPa, its pressure derivative $$K'=9.9pm 3.6$$ and the temperature derivative of the bulk modulus $$(delta K_{T}/delta T)_{P}=-0.0022 pm 0.0015$$ GPa/K at 1773K. The small bulk modulus of the hydrous peridotite magma compared with that of the dry peridotite magma reflects the effect of water, which is more compressible than the silicate melt.

Journal Articles

Viscosity and density measurements of melts and glasses at high pressure and temperature by using the multi-anvil apparatus and synchrotron X-ray radiation

Otani, Eiji*; Suzuki, Akio*; Ando, Ryota*; Urakawa, Satoru*; Funakoshi, Kenichi*; Katayama, Yoshinori

Advances in High-Pressure Technology for Geophysical Applications, p.195 - 209, 2005/09

This paper summarizes the techniques for the viscosity and density measurements of silicate melt and glasses at high pressure and temperature by using the X-ray radiography and absorption techniques in the third generation synchrotron radiation facility, SPring-8, Japan. The falling sphere method using in situ X-ray radiography makes it possible to measure the viscosity of silicate melts to the pressures above 6 GPa at high temperature. We summarize the details of the experimental technique of the viscosity measurement, and the results of the measurements of some silicate melts such as the albite and diopside-jadeite systems. X-ray absorption method is applied to measure the density of the silicate glasses such as the basaltic glass and iron sodium disilicate glass up to 5 GPa at high temperature. A diamond capsule, which is not reactive with the glass, is used for the density measurement of the glasses. The present density measurement of the glasses indicates that this method is useful for measurement of the density of silicate melts at high pressure and temperature.

Journal Articles

Phase relationships and equations of state for FeS at high pressures and temperatures and implications for the internal structure of Mars

Urakawa, Satoru*; Someya, Keiko*; Terasaki, Hidenori*; Katsura, Tomoo*; Yokoshi, Sho*; Funakoshi, Kenichi*; Utsumi, Wataru; Katayama, Yoshinori; Sueda, Yuichiro*; Irifune, Tetsuo*

Physics of the Earth and Planetary Interiors, 143-144, p.469 - 479, 2004/06

 Times Cited Count:53 Percentile:71.64(Geochemistry & Geophysics)

no abstracts in English

Journal Articles

Post-spinel transition in Mg$$_{2}$$SiO$$_{4}$$ determined by high ${it P-T}$ in situ X-ray diffractometry

Katsura, Tomoo*; Yamada, Hitoshi*; Shimmei, Toru*; Kubo, Atsushi*; Ono, Shigeaki*; Kanzaki, Masami*; Yoneda, Akira*; Walter, M. J.*; Ito, Eiji*; Urakawa, Satoru*; et al.

Physics of the Earth and Planetary Interiors, 136(1-2), p.11 - 24, 2003/04

 Times Cited Count:162 Percentile:94.39(Geochemistry & Geophysics)

no abstracts in English

Journal Articles

Viscosity change and structural transition of molten Fe at 5 GPa

Terasaki, Hidenori*; Kato, Takumi*; Urakawa, Satoru*; Funakoshi, Kenichi*; Sato, Kiminori*; Suzuki, Akio*; Okada, Taku

Geophysical Research Letters, 29(8), p.68_1 - 68_3, 2002/05

The in situ viscosity measurements of the pure molten Fe under high pressures were made by falling sphere X-ray radiography method. Viscosity coefficients at about 2000 K were 15-24 mPa s at 2.7-5.0 GPa, and 4-9 mPa s at 5.0-7.0 GPa. Drastic decrease was found at around 5 GPa, at which stable solid phase below the melting temperatures change from delta (bcc) to gamma (fcc) phases. The observation indicates the possibility that the structural change in the molten Fe occurs in a narrow pressure interval (1 GPa) at the similar condition with the phase transformation in the solid.

Journal Articles

High-pressure phase relationships for FeS

Urakawa, Satoru*; Hasegawa, Masayuki*; Yamakawa, Junji*; Funakoshi, Kenichi*; Utsumi, Wataru

High Pressure Research, 22(2), p.491 - 494, 2002/01

 Times Cited Count:3 Percentile:29.83(Physics, Multidisciplinary)

no abstracts in English

Journal Articles

Mechanisms and kinetics of the post-spinel transformation in Mg$$_{2}$$SiO$$_{4}$$

Kubo, Tomoaki*; Otani, Eiji*; Kato, Takumi*; Urakawa, Satoru*; Suzuki, Akio*; Kambe, Yuichi*; Funakoshi, Kenichi*; Utsumi, Wataru; Kikegawa, Takumi*; Fujino, Kiyoshi*

Physics of the Earth and Planetary Interiors, 129(1-2), p.153 - 171, 2002/01

 Times Cited Count:47 Percentile:67.63(Geochemistry & Geophysics)

no abstracts in English

Journal Articles

The Effect of temperature, pressure, and sulfur content on viscosity of the Fe-FeS melt

Terasaki, Hidenori*; Kato, Takumi*; Urakawa, Satoru*; Funakoshi, Kenichi*; Suzuki, Akio*; Okada, Taku; Maeda, Makoto*; Sato, Jin*; Kubo, Tomoaki*; Kasai, Shizu*

Earth and Planetary Science Letters, 190(1-2), p.93 - 101, 2001/07

 Times Cited Count:47 Percentile:68(Geochemistry & Geophysics)

The Fe-FeS melt is thought to be the major candidate of the outer core material. Its viscosity is one of the most important physical properties to study the dynamics of the convection in the outer core. We performed the in situ viscosity measurement of the Fe-FeS melt under high pressure using X-ray radiography falling sphere method with a novel sample assembly. Viscosity was measures in the temperature, pressure, and compositional conditions of 1233-1923 K, 1.5-6.9 GPa, and Fe-Fe $$_{72}$$ S $$_{28}$$ (wt %), respectively. The viscosity coefficients obtained by 17 measurements change systematically in the range of 0.008-0.036 Pa s. An activation energy of the viscous flow, 30 kJ/mol, and the activation volume, 1.5 cm $$^{3}$$ /mol, are determined as the temperature and pressure dependence, and the viscosity of the Fe $$_{72}$$ S $$_{28}$$ melt is found to be smaller than that of the Fe melt by 15 %. These tendencies can be well correlated with the structural variation of the Fe-FeS melt.

Journal Articles

High pressure high temperature experiments using multi-anvil device; Method and facility

Utsumi, Wataru; Funakoshi, Kenichi*; Yagi, Naoto*; Urakawa, Satoru*; Otaka, Osamu*; Katsura, Tomoo*; Irifune, Tetsuo*; Inoue, Toru*; Uchida, Takeyuki*

Ganseki Kobutsu Kagaku, 30(2), p.100 - 101, 2001/03

no abstracts in English

Journal Articles

${it In situ}$ observation of ilmenite-perovskite phase transition in MgSiO$$_{3}$$ using synchrotron radiation

Ono, Shigeaki*; Katsura, Tomoo*; Ito, Eiji*; Kanzaki, Masami*; Yoneda, Akira*; Walter, M.*; Urakawa, Satoru*; Utsumi, Wataru; Funakoshi, Kenichi*

Geophysical Research Letters, 28(5), p.835 - 838, 2001/03

 Times Cited Count:74 Percentile:87(Geosciences, Multidisciplinary)

no abstracts in English

Journal Articles

Thermoelastic properties of the high-pressure phase of SnO$$_{2}$$ determined by in situ X-ray observations up to 30GPa and 1400K

Ono, Shigeaki*; Ito, Eiji*; Katsura, Tomoo*; Yoneda, Akira*; Walter, M.*; Urakawa, Satoru*; Utsumi, Wataru; Funakoshi, Kenichi*

Physics and Chemistry of Minerals, 27(9), p.618 - 622, 2000/11

 Times Cited Count:42 Percentile:80.3(Materials Science, Multidisciplinary)

no abstracts in English

Journal Articles

Formation of metastable assemblages and mechanisms of the grain-size reduction in the postspinel transformation of Mg$$_{2}$$SiO$$_{4}$$

Kubo, Tomoaki*; Otani, Eiji*; Kato, Takumi*; Urakawa, Satoru*; Suzuki, Akio*; Kambe, Yuichi*; Funakoshi, Kenichi*; Utsumi, Wataru; Fujino, Kiyoshi*

Geophysical Research Letters, 27(6), p.807 - 810, 2000/03

 Times Cited Count:32 Percentile:64.02(Geosciences, Multidisciplinary)

no abstracts in English

Journal Articles

On the research of the high-pressure mineral physics experimental station at BL04B1 in SPring-8

Urakawa, Satoru*; Otaka, Osamu*; Funakoshi, Kenichi*; Utsumi, Wataru

Nihon Kessho Gakkai-Shi, 42(1), p.24 - 32, 2000/02

no abstracts in English

Journal Articles

High temperature research beamline (BL04B1) at SPring-8

Utsumi, Wataru; Funakoshi, Kenichi*; Urakawa, Satoru*; Irifune, Tetsuo*; Tamura, Kozaburo*; Inui, Masanori*; Tsuji, Kazuhiko*; Shimomura, Osamu

Hoshako, 12(1), p.17 - 23, 1999/02

no abstracts in English

25 (Records 1-20 displayed on this page)