Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Nakanishi, Toshimichi*; Komatsu, Tetsuya; Ogata, Manabu; Kawamura, Makoto; Yasue, Kenichi*
Gekkan Chikyu "Kiso deta Kara Kangaeru Dai Yonkigaku No Shintenkai-I" Gogai No.71, p.148 - 155, 2022/02
The formation process of terrace topography was investigated by observing and analyzing boring core samples collected in the middle reaches of the Kumano River. It was assumed that the older terrace topography was distributed higher than the current riverbed surface. However, since tributary debris flow deposits may be thickly distributed beneath the old gyre river valley, care must be taken when using the surface of the ground as an index of uplift and erosion.
-ray analysis for volcanic rocks by JRR-3 reactorOsawa, Takahito; Fukuoka, Takaaki*
Gekkan Chikyu, 40(5), p.302 - 309, 2018/05
Contents of boron, chlorine, hydrogen, and water in volcanic rocks provide important information of magma origin. Here we describe the measurement for boron in volcanic rocks using the automatic prompt -ray analysis system installed in Japan research reactor-3 (JRR-3) at Japan atomic Energy Agency.
Fukuda, Tetsuya*; Tanase, Atsushi*; Umeda, Koji; Kobayashi, Tetsuo*
Gekkan Chikyu, 37(5), p.197 - 203, 2015/05
no abstracts in English
Okuno, Mitsuru*; Nagaoka, Shinji*; Kokubu, Yoko
Gekkan Chikyu, 37(4), p.119 - 121, 2015/04
Onidake scoria fall deposit at Goto-Fukue Island, Japan is a product of the latest eruption of the Onidake volcano group. Radiocarbon date and C/N ratio of humic soil below the deposit are 19,840
120 BP and 9.14, respectively. It shows that the soil proceeded with decomposition in part and the date might be younger than the true one. However the date is older than the result (18,090100 BP) in the soil of the same layer reported by Nagaoka and Furuyama (2004) and is consistent with stratigraphical correlation with widespread tephra such as AT and K-Ah. The calibrated date is approximately 24 cal kBP.
Ninomiya, Atsushi; Umeda, Koji; Asamori, Koichi
Gekkan Chikyu, 35(6), p.297 - 304, 2013/06
The seismic tomography study along the Niigata-Kobe Tectonic Zone revealed segmentations of the seismic velocity structure and suggests the variable origin of the high-strain-rate along the NKTZ. We compiled existing helium isotope data to inspect an implication of geographic distribution of helium isotope data to the geophysical structure of the NKTZ.
Umeda, Koji; Yasue, Kenichi; Asamori, Koichi
Gekkan Chikyu, 32(1), p.52 - 63, 2010/01
no abstracts in English
Kasahara, Junzo
Gekkan Chikyu Gogai, (51), p.5 - 10, 2005/00
None
Umeda, Koji; Furusawa, Akira*
Gekkan Chikyu, 26(6), p.395 - 400, 2004/06
no abstracts in English
Umeda, Koji; Asamori, Koichi; Oikawa, Teruki; Kakuta, Chifumi; Zhao, N.*; Kamaya, Noriko*
Gekkan Chikyu, 26(6), p.407 - 413, 2004/06
None
Tekeda, Seitetsu; Nakatsuka, Noboru; Umeda, Koji
Gekkan Chikyu, 26(6), p.332 - 338, 2004/01
None
Nakajima, Takahiro; Kumazawa, Mineo; Shigeta, Naotaka; Kunitomo, Takahiro; Nagao, Hiromichi; Matsumoto, Hiroshi*
Gekkan Chikyu Gogai, (47), 174 Pages, 2004/00
We introduce a new electromagnetic sounding method called EM-ACROSS (ElectroMagnetic - Accurately Controlled Routinely Operated Signal System). The feature of the propagation of the elecromagnetic waves is defferent from that of elastic waves. We introduce the present state of the development of a system at Tono Geoscience Center. We estimate the posivility of the exploration of deep Earth's crust.
Nakajima, Takahiro; Kunitomo, Takahiro; Nagao, Hiromichi; Kumazawa, Mineo; Shigeta, Naotaka
Gekkan Chikyu Gogai, (47), p.179 - 184, 2004/00
We have developed an electromagnetic sounding method, called EM-ACROSS (ElectroMagnetic - Accurately Controlled Routinely Operated Signal System), which can be used for the exploration of the frequency range below hundreds hertz. A trial observation has been done at Tono area for more than one year. We have obtained the accurate averaged transfer function, and also observed its temporal variation.
Hasada, Yoko; Kumazawa, Mineo; Kayoko, Tsuruga,; Kunitomo, Takahiro
Gekkan Chikyu Gogai, (47), p.61 - 68, 2004/00
A data set acquired by ACROSS is the transfer functions between transmitted signal and received one sampled within limited bandwidth. We have developed a method to extract event localized in time domain from frequency-domain transfer function and estimate the traveltimes, which is called the Sompi event analysis.
Kayoko, Tsuruga; Kumazawa, Mineo; Kunitomo, Takahiro; Shigeta, Naotaka
Gekkan Chikyu Gogai, (47), 34 Pages, 2004/00
Focusing on the cover layer materials (as the Radon Barrier Materials), which could have the effect to restrain the radon from scattering into the air and the effect of the radiation shielding, we produced the radon barrier materials with crude bentonite on an experimental basis, using the rotary type comprehensive unit for grinding and mixing, through which we carried out the evaluation of the characteristics thereof.
Tsuruga, Kayoko; Kunitomo, Takahiro; Hasada, Yoko; Kumazawa, Mineo; Shigeta, Naotaka;
Gekkan Chikyu Gogai, (47), 95 Pages, 2004/00
There is a problem of vibration in a diagnosis system of helical evaporator tubes installed in a nuclear power station. Numerical simulations are implemented on the assumption that the vibration is caused by the Coulomb's friction. An analytical model is derived as a large scale nonlinear vibration system and a lot of computational cost would be required to carry out the simulations. The Transfer Influence Coefficient Method, which has high accuracy and efficiency in numerical computations, is applied and efficiently implements the simulations. The vibrations are qualitatively reproduced by the simulations. It enables us to make a pre-evaluation of several means to suppress the vibrations are qualitatively reproduced by the simulations. It enables us to make a pre-evaluation of several means to suppreess the vibration and the most effective devise is expected through the simulation.
Junzo, Kasahara; Kayoko, Tsuruga; Hasada, Yoko; *; Kumazawa, Mineo; Kunitomo, Takahiro
Gekkan Chikyu Gogai, (47), 141 Pages, 2004/00
Focusing on the cover layer materials (as the Radon Barrier Materials), which could have the effect to restrain the radon from scattering into the air and the effect of the radiation shielding, we produced the radon barrier materials with crude bentonite on an experimental basis, using the rotary type comprehensive unit for grinding and mixing, through which we carried out the evaluation of the characteristics thereof.
Nagano, Tetsushi
Gekkan Chikyu, 22(7), p.429 - 434, 2000/07
no abstracts in English
