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Ishihara, Takanori; Nishiyama, Nariaki; Kato, Yuri; Shimada, Koji
JAEA-Data/Code 2024-013, 17 Pages, 2024/12
JAEA-Data-Code-2024-013.pdf:2.8MB
JAEA-Data-Code-2024-013-appendix(DVD-ROM).zip:2305.14MB
Japan Atomic Energy Agency and Central Research Institute of Electric Power Industry conducted collaborative research as a part of "Establishment of Advanced Technology for Evaluating the Long-term Geosphere Stability on Geological Disposal Project of Radioactive Waste (Fiscal Years 2018-2022)" under a contract with the Ministry of Economy, Trade and Industry. We conducted case studies of the effects of major natural phenomena (volcanic and igneous activity, deep-seated fluid, earthquakes and faulting, and uplift and erosion) required to be investigated and evaluated in relation to the selection and modeling of geological environments suitable for geological disposal in Japan, by applying techniques based on the latest research in various academic fields. Through these studies, we accumulated the knowledge necessary to solve problems and advanced our investigation and evaluation techniques. For effectively utilization of these achievements, we organized them in a Geographic Information System (GIS) and compiled them into a dataset that can be viewed in QGIS that free GIS software. This report described the procedure for creating this dataset and how to use it. With publishing this dataset, it is expected that not only seamlessly sharing information within each research field become possible, but also facilitating access and utilization of the research results by researchers in other fields and engineers involved in the geological disposal project.
Niwa, Masakazu; Shimada, Akiomi; Asamori, Koichi; Sueoka, Shigeru; Komatsu, Tetsuya; Nakajima, Toru; Ogata, Manabu; Uchida, Mao; Nishiyama, Nariaki; Tanaka, Kiriha; et al.
JAEA-Review 2024-035, 29 Pages, 2024/09
JAEA-Review-2024-035.pdf:1.24MB
This report is a plan of research and development (R&D) on geosphere stability for long-term isolation of high-level radioactive waste (HLW) in Japan Atomic Energy Agency (JAEA), in fiscal year 2024. The objectives and contents of this research are described in detail based on the JAEA 4th Medium- and Long-term Plan (fiscal years 2022-2028). In addition, the background of this research is described from the necessity and the significance for site investigation and safety assessment, and the past progress. The plan framework is structured into the following categories: (1) Development and systematization of investigation techniques, (2) Development of models for long-term estimation and effective assessment, (3) Development of dating techniques.
Niwa, Masakazu; Shimada, Koji; Terusawa, Shuji*; Goto, Akira*; Nishiyama, Nariaki; Nakajima, Toru; Ishihara, Takanori; Hakoiwa, Hiroaki
Island Arc, 33(1), p.e12516_1 - e12516_16, 2024/02
Times Cited Count：2 Percentile：20.98(Geosciences, Multidisciplinary)To investigate the geological evidence of near-surface crustal deformations in a high-strain shear zone that has been geodetically identified but not associated with clear tectonic landforms, a fieldwork was conducted in E-W trending southern Kyushu high-strain shear zone, Japan. According to our study, an investigation based on the slip data from minor faults and the occurrences of fracture zones could help to identify a concealed fault that is small in terms of size to record tectonic landforms but can trigger large earthquakes.
Murase, Kiyoka*; Kataoka, Ryuho*; Nishiyama, Takanori*; Sato, Kaoru*; Tsutsumi, Masaki*; Tanaka, Yoshimasa*; Ogawa, Yasunobu*; Sato, Tatsuhiko
Space Weather, 21(12), p.e2023SW003651_1 - e2023SW003651_11, 2023/12
Times Cited Count：3 Percentile：24.54(Astronomy & Astrophysics)Comprehensive understandings of their global impact on the atmosphere require whole pictures of spatio-temporal distributions of the ionization due to them. We estimate the altitude profiles of the ionization rate during the space weather event occurred in September 2017 by using the Particle and Heavy Ion Transport code System (PHITS) with input of the particle fluxes obtained by satellites. The estimates are then compared with measurements of the ionization altitude, ionization intensity, and electron density by the radars in the polar region such as the PANSY radar at Syowa Station and the EISCAT in Tromso, Norway. We conclude that the PHITS simulation results reproduce those ionizations measured by ground-based instruments with inputs of observed ionization sources by satellites within a factor of 2.
Niwa, Masakazu; Shimada, Koji; Sueoka, Shigeru; Fujita, Natsuko; Yokoyama, Tatsunori; Ogita, Yasuhiro; Fukuda, Shoma; Nakajima, Toru; Kagami, Saya; Ogata, Manabu; et al.
JAEA-Review 2023-017, 27 Pages, 2023/10
JAEA-Review-2023-017.pdf:0.94MB
This report is a plan of research and development (R&D) on geosphere stability for long-term isolation of high-level radioactive waste (HLW) in Japan Atomic Energy Agency (JAEA), in fiscal year 2023. The objectives and contents in fiscal year 2023 are described in detail based on the JAEA 4th Medium- and Long-term Plan (fiscal years 2022-2028). In addition, the background of this research is described from the necessity and the significance for site investigation and safety assessment, and the past progress. The plan framework is structured into the following categories: (1) Development and systematization of investigation techniques, (2) Development of models for long-term estimation and effective assessment, (3) Development of dating techniques.
Niwa, Masakazu; Shimada, Koji; Sueoka, Shigeru; Ishihara, Takanori; Ogawa, Hiroki; Hakoiwa, Hiroaki; Watanabe, Tsuyoshi; Nishiyama, Nariaki; Yokoyama, Tatsunori; Ogata, Manabu; et al.
JAEA-Research 2023-005, 78 Pages, 2023/10
JAEA-Research-2023-005.pdf:6.51MB
This annual report documents the progress of research and development (R&D) in the 1st fiscal year of the Japan Atomic Energy Agency 4th Medium- and Long-term Plan (fiscal years 2022-2028) to provide the scientific base for assessing geosphere stability for long-term isolation of high-level radioactive waste. The plan framework is structured into the following categories: (1) Development and systematization of investigation techniques, (2) Development of models for long-term estimation and effective assessment, (3) Development of dating techniques. The current status of R&D activities with previous scientific and technological progress is summarized.
Murase, Kiyoka*; Kataoka, Ryuho*; Nishiyama, Takanori*; Nishimura, Koji*; Hashimoto, Taishi*; Tanaka, Yoshimasa*; Kadokura, Akira*; Tomikawa, Yoshihiro*; Tsutsumi, Masaki*; Ogawa, Yasunobu*; et al.
Journal of Space Weather and Space Climate (Internet), 12, p.18_1 - 18_16, 2022/06
Times Cited Count：5 Percentile：32.99(Astronomy & Astrophysics)We identified two energetic electron precipitation (EEP) events during the growth phase of moderate substorms and estimated the mesospheric ionization rate for an EEP event for which the most comprehensive dataset from ground-based and space-born instruments was available. The mesospheric ionization signature reached below 70 km altitude and continued for ~15 min until the substorm onset, as observed by the PANSY radar and imaging riometer at Syowa Station in the Antarctic region. We also used energetic electron flux observed by the Arase and POES 15 satellites as the input for the air-shower simulation code PHITS to quantitatively estimate the mesospheric ionization rate. Combining the cutting-edge observations and simulations, we shed new light on the space weather impact of the EEP events during geomagnetically quiet times, which is important to understand the possible link between the space environment and climate.
Kataoka, Ryuho*; Nishiyama, Takanori*; Tanaka, Yoshimasa*; Kadokura, Akira*; Uchida, Herbert Akihito*; Ebihara, Yusuke*; Ejiri, Mitsumu*; Tomikawa, Yoshihiro*; Tsutsumi, Masaki*; Sato, Kaoru*; et al.
Earth, Planets and Space (Internet), 71(1), p.9_1 - 9_10, 2019/12
Times Cited Count：11 Percentile：37.69(Geosciences, Multidisciplinary)Transient ionization of the mesosphere was detected at around 65 km altitude during the isolated auroral expansion occurred at 2221-2226 UT on June 30, 2017. A general-purpose Monte Carlo particle transport code PHITS suggested that significant ionization is possible in the middle atmosphere due to auroral X-rays from the auroral electrons of 
10 keV.
Onoue, Ryuji; Kawamata, Takanori; Otsuka, Kaoru; Sekine, Katsunori; Koike, Sumio; Gorai, Shigeru; Nishiyama, Yutaka; Fukasaku, Akitomi
JAEA-Review 2012-010, 116 Pages, 2012/03
JAEA-Review-2012-010-01.pdf:65.41MBJAEA-Review-2012-010-02.pdf:81.33MBJAEA-Review-2012-010-03.pdf:87.98MBJAEA-Review-2012-010-04.pdf:45.25MB
JMTR is a light water moderated and cooled tank-type reactor, and its thermal power is 50 MW. The JMTR is categorized as high flux testing reactors in the world. The JMTR has been utilized for irradiation experiments of nuclear fuels and materials, as well as for radioisotope productions since the first criticality in March 1968 until August 2006. JAEA is decided to refurbish the JMTR as an important fundamental infrastructure to promote the nuclear research and development. And The JMTR refurbishment work is carried out for 4 years from 2007. Before refurbishment work, from August 2006 to March 2007, all concerned renewal facilities were selected from evaluation on their damage and wear in terms of aging. Facilities which replacement parts are no longer manufactured or not likely to be manufactured continuously in near future, are selected as renewal ones. Replace priority was decided with special attention to safety concerns. A monitoring of aging condition by the regular maintenance activity is an important factor in selection of continuous using after the restart. In this report, renewal of the cooling system within refurbishment facilities in the JMTR is summarized.
Onoue, Ryuji; Kawamata, Takanori; Otsuka, Kaoru; Koike, Sumio; Nishiyama, Yutaka; Fukasaku, Akitomi
JAEA-Review 2011-018, 17 Pages, 2011/06
JAEA-Review-2011-018.pdf:2.71MB
JMTR is a light water moderated and cooled tank-type reactor, and its thermal power is 50 MW. The JMTR is categorized as high flux testing reactors in the world. The JMTR has been utilized for irradiation experiments of nuclear fuels and materials, as well as for radioisotope productions since the first criticality in March 1968 until August 2006. JAEA decided to refurbish the JMTR as an important fundamental infrastructure to promote the nuclear research and development. The refurbishment work was started from 2007, and restart is planned in 2011. Renewal facilities were selected from evaluation on their damage and wear in terms of aging. Facilities whose replacement parts are no longer manufactured or not likely to be manufactured continuously in near future, are selected as renewal ones. Replacement priority was decided with special attention to safety concerns. A monitoring of aging condition by the regular maintenance activity is an important factor in selection of continuous using after the restart. In this report, renewal of the cooling system within refurbishment facilities in the JMTR is summarized.
Ebisawa, Hiroyuki; Hanakawa, Hiroki; Asano, Norikazu; Kusunoki, Hidehiko; Yanai, Tomohiro; Sato, Shinichi; Miyauchi, Masaru; Oto, Tsutomu; Kimura, Tadashi; Kawamata, Takanori; et al.
JAEA-Technology 2009-030, 165 Pages, 2009/07
JAEA-Technology-2009-030.pdf:69.18MB
The condition of facilities and machinery used continuously were investigated before the renewal work of JMTR on FY 2007. The subjects of investigation were reactor building, primary cooling system tanks, secondary cooling system piping and tower, emergency generator and so on. As the result, it was confirmed that some facilities and machinery were necessary to repair and others were used continuously for long term by maintaining on the long-term maintenance plan. JMTR is planed to renew by the result of this investigation.
Uchida, Mao; Nishiyama, Nariaki; Ogata, Manabu; Komatsu, Tetsuya; Tsukahara, Yuzuko; Ishihara, Takanori; Kawamura, Makoto; Nakanishi, Toshimichi*; Terada, Tatsuya*; Hosoya, Takashi*
no journal, ,
no abstracts in English
Terada, Tatsuya*; Nishiyama, Nariaki; Komatsu, Tetsuya; Uchida, Mao; Ogata, Manabu; Ishihara, Takanori; Kawamura, Makoto; Nakanishi, Toshimichi*
no journal, ,
no abstracts in English
Sr/
Sr ratios inside the Toki granite, Central Japan; Implication for the intrusion and cooling process of a granitic plutonYuguchi, Takashi; Tsuruta, Tadahiko; Kunimaru, Takanori; Nishiyama, Tadao*
no journal, ,
no abstracts in English
Uchida, Mao; Nishiyama, Nariaki; Ogata, Manabu; Komatsu, Tetsuya; Tsukahara, Yuzuko; Ishihara, Takanori; Kawamura, Makoto; Nakanishi, Toshimichi*; Terada, Tatsuya*; Hosoya, Takashi*
no journal, ,
no abstracts in English
Abe, Noriaki*; Nakajima, Toru*; Nishiyama, Nariaki; Hakoiwa, Hiroaki*; Ishihara, Takanori*; Kida, Fukuka; Ogita, Yasuhiro; Niwa, Masakazu
no journal, ,
no abstracts in English
Nishiyama, Nariaki; Nakajima, Toru; Goto, Akira*; Abe, Noriaki; Hakoiwa, Hiroaki; Ishihara, Takanori; Nagata, Mitsuhiro*; Shimada, Koji; Niwa, Masakazu
no journal, ,
Ogata, Manabu; Tsukahara, Yuzuko; Nishiyama, Nariaki; Komatsu, Tetsuya; Uchida, Mao; Kawamura, Makoto; Ishihara, Takanori; Nakanishi, Toshimichi*
no journal, ,
Terrace to terrace (TT) method is mainly used for estimating uplift rate on mountain areas of Japan on 10
-year time scale. However, this method cannot be applied to the area with poor distribution of fluvial terraces. In such area, the method based on the emergence ages of the fluvial landform, e.g., an abandoned river valley around a cutoff spur, and the relative elevation between old and present reiver bed is expected instead of TT method. This method calculates the river-incision rate by dividing the relative elevation by the emergence age. The river-incision rate is equal to the uplift rate if the river is at equilibrium (graded stream). We are investigating the fluvial landform in the Oi River basin for verifying this method. In this presentation, we will present the incision and uplift rate estimated by feldspar OSL dating results.
Yuguchi, Takashi; Iwano, Hideki*; Hattori, Kentaro*; Sakata, Shuhei*; Sueoka, Shigeru; Danhara, Toru*; Hirata, Takafumi*; Ishibashi, Masayuki; Kunimaru, Takanori; Nishiyama, Tadao*
no journal, ,
no abstracts in English
Yuguchi, Takashi; Iwano, Hideki*; Danhara, Toru*; Hirata, Takafumi*; Sueoka, Shigeru; Hattori, Kentaro*; Sakata, Shuhei*; Ishibashi, Masayuki; Kunimaru, Takanori; Nishiyama, Tadao*
no journal, ,
no abstracts in English
Kawamata, Takanori; Otsuka, Kaoru; Sekine, Katsunori; Onoue, Ryuji; Koike, Sumio; Nishiyama, Yutaka
no journal, ,
no abstracts in English
