Ogata, Manabu; King, G. E.*; Herman, F.*; Sueoka, Shigeru
Earth and Planetary Science Letters, 591, p.117607_1 - 117607_14, 2022/08
Optically stimulated luminescence (OSL)-thermometry can be used to reconstruct the thermal structure in slowly denuded regions where infrared stimulated luminescence (IRSL) signals of samples obtained from deep boreholes are measured and evaluated with depth. Until now, only one study has explored this approach, using a target mineral of Na-feldspar. In this study, we applied multi-OSL-thermometry to K-feldspar obtained from deep borehole core samples (MIZ-1) drilled at the Tono region, central Japan, which is a well-documented thermally stable crustal environment. The inverted temperature for the IRSL 50 C of the samples at a depth of 1 km (40 C) were consistent with the in-situ temperature. The results suggest that the application of OSL-thermometry to K-feldspar in a borehole is useful to reconstruct the paleothermal condition.
Lifton, N.*; Sato, Tatsuhiko; Dunai, T. J.*
Earth and Planetary Science Letters, 386, p.149 - 160, 2014/01
We have developed a new scaling model based on analytical approximations to modeled fluxes of the main atmospheric cosmic-ray particles responsible for cosmogenic nuclide production. A key advantage of this new model over previous Monte Carlo models of cosmogenic nuclide production is that it allows for the rapid estimation of scaling factors based on flexible geomagnetic and solar inputs - as newer and better records become available, the model is parameterized to allow their substitution.
Okubo, Ayako; Obata, Hajime*; Gamo, Toshitaka*; Yamada, Masatoshi*
Earth and Planetary Science Letters, 339-340, p.139 - 150, 2012/07
Vertical distributions of total Th and dissolved Th were determined in the mid-latitudes of the North Pacific Ocean. Th in the Pacific Ocean have been described well using the reversible-scavenging model. However, we observed the depletion of total Th. The enhanced vertical eddy diffusion derived from the complex topography of the western Pacific Ocean might promote bottom scavenging and transport of the low Th in deep water to the upper layers.
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
The density of the Apollo 14 black glass melt, which has the highest TiO 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.
Sakamaki, Tatsuya*; Otani, Eiji*; Urakawa, Satoru*; Suzuki, Akio*; Katayama, Yoshinori
Earth and Planetary Science Letters, 287(3-4), p.293 - 297, 2009/10
The density of hydrous peridotite magma containing 5wt.% HO 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 GPa, its pressure derivative and the temperature derivative of the bulk modulus 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.
Murakami, Takashi*; Ito, Junichi*; Utsunomiya, Satoshi*; Kasama, Takeshi*; Kozai, Naofumi; Onuki, Toshihiko
Earth and Planetary Science Letters, 224(1-2), p.117 - 129, 2004/07
no abstracts in English
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
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 S (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 /mol, are determined as the temperature and pressure dependence, and the viscosity of the Fe S 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.
; *; *; *
Earth and Planetary Science Letters, 5(1), p.47 - 51, 1968/09
no abstracts in English