Dome design of JNLT     

I. Mikami  N. Itoh  K. Miyawaki  H. Ando  T. Noguchi  M. Nakagiri  E. Watanabe 《Astrophysics and Space Science》1989,160(1-2):173-181

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Heating of chromospheric magnetic features by direct current dissipation     

Satoshi Hinata 《Solar physics》1983,87(1):95-101

It is shown that the direct current dissipation is very unlikely to be the heat source of the coronal loop, because it accompanies unacceptably high heating rate in the chromospheric portion of the loop. This also suggests that a rather weak current density can supply the heat to a small (R < 10⁷ cm) chromospheric magnetic features. A larger magnetic element may be heated by the direct current dissipation only if the current changes directions within a single element so that the generated magnetic field is sufficiently weak to insure MHD stability.  相似文献   

Distribution of fault rocks in the fracture zone of the Nojima Fault at a depth of 1140 m: Observations from the Hirabayashi NIED drill core     

Kenta Kobayashi  Satoshi Hirano  Takashi Arai  Ryuji Ikeda  Kentaro Omura  Hiroyuki Sano  Takashi Sawaguchi  Hidemi Tanaka  Tomoaki Tomita  Naoto Tomida  Tatsuo Matsuda  Akiko Yamazaki 《Island Arc》2001,10(3-4):411-421

Abstract Characteristics of deformation and alteration of the 1140 m deep fracture zone of the Nojima Fault are described based on mesoscopic (to the naked eye) and microscopic (by both optical and scanning electron microscopes) observations of the Hirabayashi National Research Institute for Earth Science and Disaster Prevention (NIED) drill core. Three types of fault rocks; that is, fault breccia, fault gouge and cataclasite, appear in the central part of the fault zone and two types of weakly deformed and/or altered rocks; that is, weakly deformed and altered granodiorite and altered granodiorite, are located in the outside of the central part of the fault zone (damaged zone). Cataclasite appears occasionally in the damaged zone. Six distinct, thin foliated fault gouge zones, which dip to the south-east, appear clearly in the very central part of the fracture zone. Slickenlines plunging to the north-east are observed on the surface of the newest gouge. Based on the observations of XZ thin sections, these slickenlines and the newest gouge have the same kinematics as the 1995 Hyogo-ken Nanbu earthquake (Kobe earthquake), which was dextral-reverse slip. Scanning electron microscopy observations of the freeze-dried fault gouge show that a large amount of void space is maintained locally, which might play an important role as a path for fluid migration and the existence of either heterogeneity of pore fluid pressure or strain localization.  相似文献   

Examination of mineral assemblage and chemical composition in the fracture zone of the Nojima Fault at a depth of 1140 m: Analyses of the Hirabayashi NIED drill cores     

Tatsuo Matsuda  Takashi Arai  Ryuji Ikeda  Kentaro Omura  Kenta Kobayashi  Hiroyuki Sano  Takashi Sawaguchi  Hidemi Tanaka  Tomoaki Tomita  Naoto Tomida  Satoshi Hirano  Akiko Ymazaki 《Island Arc》2001,10(3-4):422-429

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Mineralogy of phyllosilicate-rich micrometeorites and comparison with Tagish Lake and Sayama meteorites     

Takaaki Noguchi  Tomoki NakamuraWataru Nozaki 《Earth and Planetary Science Letters》2002,202(2):229-246

Four phyllosilicate-rich micrometeorites (MMs) were investigated by a synchrotron radiation X-ray diffraction technique and transmission electron microscopy. Three are saponite-rich MMs and one is a serpentine-rich one. In the saponite-rich MMs, we could not find serpentine, and vice versa in the serpentine-rich MM. In the saponite-rich MMs, major constituent minerals are saponite, Fe- and Ni-bearing sulfides, and magnetite. Two saponite-rich MMs contain fine-grained magnesiowüstite-rich aggregates. The aggregates consist of <50 nm polygonal magnesiowüstite coexisting with minor Fe sulfide grains. Their texture, chemical composition, and the result of heating experiments on matrix fragments of the Tagish Lake carbonaceous chondrite strongly suggest that these aggregates were formed by the breakdown of Mg- and Fe-rich carbonate grains when the MMs entered the Earth’s atmosphere. The estimated major mineral assemblage of the saponite-rich MMs before entering the Earth’s atmosphere is very similar to that of the Tagish Lake carbonate-rich lithology, and we suggest that the MMs and the meteorite were derived from similar asteroids. The major mineral assemblage and texture of the matrix of serpentine-rich MM are similar to the matrix of the Sayama CM2 chondrite that experienced heavy aqueous alteration. Chemical compositions of serpentine in the MM suggest that the degree of aqueous alteration of the MM is weaker than that of Sayama. In the MM, cronstedtite does not coexist with tochilinite, which is different from CM2 chondrites that experienced weak to moderate aqueous alteration. However, the possibility that the serpentine-rich MM was derived from the CM chondrite asteroid cannot be ruled out, because tochilinite can be preferentially decomposed during atmospheric entry heating due to its lower decomposition temperature than that of cronstedtite.  相似文献   

Prediction of volcanic eruption by measuring the chemical composition and amounts of gases     

Kimio Noguchi  Hiroshi Kamiya 《Bulletin of Volcanology》1963,26(1):367-378

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Content and behavior of fluorine in Japanese quaternary volcanic rocks and petrogenetic application     

Ken-Ichi Ishikawa  Satoshi Kanisawa  Ken-Ichiro Aoki 《Journal of Volcanology and Geothermal Research》1980,8(2-4)

Fluorine contents in about 160 representative Quaternary volcanic rocks and 15 hornblende and biotite phenocrysts in a calc-alkali series in Japan have been determined by a selective ion-electrode method. Tholeiites have the lowest contents and the narrowest range (58–145 ppm), while alkali basalts have the highest contentws and the widest range (301–666 ppm), high-alumina basalts have intermediate values (188–292 ppm). F contents in basalts clearly increase from east to west across the Japanese Islands, as do alkalies, P₂O₅ REE, U, Th and H₂O.The volcanic rocks studied are divided into two groups on the basis of F: (1) witt, increasing % SiO₂ or advancing fractionation, F contents show either progressive enrichment; or (2) with increasing fractionation, F contents show rather constant values. The former is produced by fractionation of anhydrous phases from basalt to mafic andesite magmas; the tholeiite series of Nasu volcanic zone (outer zone), northeastern, Japan is a typical example. The latter group is derived through separation of amphibole-bearing phases from basaltic magmas at various depths from upper mantle (about 30 km) to upper crust; the alkali series in southwestern Japan and the calc-alkali series of Chokai volcanic zone (inner zone), northeastern Japan, are examples.  相似文献   

Exploration of Ōtake steam field     

T. Noguchi 《Bulletin of Volcanology》1966,29(1):529-543

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Expansion of the Nishinomiya Built Environment Database     

Kohiyama  Masayuki  Yamashita  Norihiko  Sato  Tadanobu  Hengjian  Lu  Maki  Norio  Tanaka  Satoshi  Hayashi  Haruo 《Natural Hazards》2003,29(3):501-522

The Nishinomiya Built Environment Database, which can be used to analyze the disaster process of the 1995 Hanshin-Awaji Earthquake Disaster in Nishinomiya City, has been expanded with new data entries. The database contains the following very detailed datasets: (1) the urbanization area base map, (2) casualty data, (3) three sets of building damage data surveyed by the Nishinomiya City, the Architectural Institute of Japan and the City Planning Institute of Japan, and the Kobe University, (4) building property data based on the real estate tax roll, (5) photographs of the damaged buildings with the information on the place and orientation of the picture, and (6) the estimated distribution of the seismic ground motion. The seismic ground motion was simulated for the southern part of Nishinomiya City and two verification sites in Kobe City and Amagasaki City. In the simulation, the borehole data of public facilities were used to model the surface soils as one-dimensional layers, taking into consideration the fact that the spatial distribution of the sediment/basement interface forms a slope. The model of the fault rupture process simulated the characteristics of the seismic motion at basement level, and amplification effects of the surface layers were evaluated based on multiple reflection theory. The distribution of peak ground acceleration and peak ground velocity was estimated from acceleration response spectra at each borehole point. In addition, the relationship between simulated seismic ground motion and building damage was studied based on newly proposed band-passed spectrum intensity using the expanded database. This confirmed that detailed categorization is necessary in order to evaluate the fragility functions, especially for reinforced concrete structures. The database should provide fundamental information for identifying the relationship between the ground motions and the extent and pattern of building damage, or the pattern of the occurrence of casualties.Presently  相似文献   

Equivalent linear method considering frequency dependent characteristics of stiffness and damping   总被引：4，自引：0，他引：4  

Nozomu Yoshida  Satoshi Kobayashi  Iwao Suetomi  Kinya Miura 《Soil Dynamics and Earthquake Engineering》2002,22(3)

Equivalent linear dynamic response analysis of ground is based on complex moduli and Fourier series expansion; therefore, it is not an equivalent method but an approximate method. Two deficiencies in the conventional equivalent linear method represented by SHAKE are described first. The maximum shear strength is overestimated, resulting in overestimation of the peak acceleration under a strong ground motion, and the amplification is underestimated at high frequency. The latter sometimes results in underestimation of the peak acceleration under weak ground shaking, and gives an incident wave with unrealistic large accelerations or a divergence of analysis in deconvolution analysis under strong ground motion. Both deficiencies are shown to come from the same cause, i.e. computing the effective strain as a constant fraction of the maximum strain. Since this is a key concept of the equivalent linear analysis, one cannot overcome both deficiencies at the same time in the conventional method. An apparent frequency dependence in stiffness and damping is shown to appear in the dynamic response, although soil itself does not show frequency dependent characteristics. Following this observation, the effective strain is expressed in terms of frequency from the similarity concept of the strain–frequency relationship between time domain and frequency domain. This enables the reduction of both deficiencies at the same time, resulting in a marked improvement in the equivalent linear analysis. The accuracy of the proposed method is examined by the simulations of three vertical array records during large earthquakes. The proposed method always gives much better prediction than conventional equivalent linear methods for both convolution and deconvolution analyses, and it is confirmed to be applicable at more than 1% shear strain.  相似文献