Organization of research results into GIS dataset in "Establishment of Advanced Technology for Evaluation the Long-term Geosphere Stability on Geological Disposal Project of Radioactive Waste FY 2018 to 2022"

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.

Analysis of the stress field around concealed active fault from minor faults-slip data collected by geological survey; An Example in the 1984 Western Nagano Earthquake region

Nishiyama, Nariaki; Nakajima, Toru; Goto, Akira*; Hakoiwa, Hiroaki; Nagata, Mitsuhiro; Shimada, Koji; Niwa, Masakazu

Earth and Space Science (Internet), 11(6), p.e2023EA003360_1 - e2023EA003360_15, 2024/06

https://doi.org/10.1029/2023EA003360

Earthquakes with magnitudes of 6-7 have been reported even in various active tectonic settings where fault deformation topography have not been detected. Therefore, delineating concealed active faults generating such earthquakes is necessary to reduce earthquake damage; however, few studies exist to provide its clues regarding such faults. The 1984 Western Nagano Earthquake in Japan was a main shock with a magnitude of Mj 6.8 and a depth of 2 km at the source. Solid bedrocks are well-exposed in the earthquake source region; however, no surface rupture have been identified, and the active fault is known to be concealed. In this study, we collected data on striations observed in fractures by geological survey around the source area of the 1984 Western Nagano Earthquake. Using the collected data, the multiple inverse method was used to estimate the stresses that affected the striation formation. Consequently, stresses similar to acting faults in this area were detected in minor faults around the known concealed active fault. This suggests that the minor faults might be part of the damage zone that has been developed around the concealed active fault. Some minor faults were recognized in Quaternary volcanic rocks, confirming that they experienced displacements recently. This study indicates the possibility of detecting concealed active faults in the bedrock by geological survey.

Research plan on geosphere stability for long-term isolation of radioactive waste (Scientific program for fiscal year 2023)

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.

Distribution of Quaternary volcanic dike under the edifices and evaluation of central conduit stability by topographic analysis using contour lines

Nishiyama, Nariaki; Kawamura, Makoto; Umeda, Koji*; Niwa, Masakazu

Oyo Chishitsu, 64(3), p.98 - 111, 2023/08

https://doi.org/10.5110/jjseg.64.98

It is important to accumulate research examples on the spatial distribution of dikes under volcanic edifices for risk assessment in volcanic disaster prevention and site selection and safety assessment for the geological disposal of high-level radioactive waste. The topography of volcanoes is considered to represent the location of magma intrusion associated with volcanic activity and its history. In this study, we attempted to determine the predominant orientation of radial dikes and evaluate the central conduit stability based on the distribution, centroid, and area of contour lines comprising the volcanic edifices using GIS-based topographic analysis. As a result of the topographic analysis, the predominant orientation of the dikes was successfully shown for the volcanoes with stable conduits. On the other hand, this analysis was not suitable for determine the predominant orientation of dikes in volcanoes with unstable conduits, thus the applicable range of this analysis is considered to be determined by the conduit stability. In addition, the conduit stability can be evaluated by using the area data of contour polygons, which represents the scope of application to the method for determination of the predominant orientation of dikes. This means that the conduit stability during volcanic activity can be evaluated even for volcanoes of which activity history is not yet known, and that topographic analysis is a useful tool for this purpose. The use of topographic analysis in this study will be expected to provide a new scale for the history of volcanic activity.

A GIS-based approach for geomorphological analysis of volcanic edifices to estimate latent magma plumbing system (Contract research)

Nishiyama, Nariaki; Goto, Akira*; Tsukahara, Yuzuko; Kawamura, Makoto; Umeda, Koji*; Niwa, Masakazu

JAEA-Testing 2022-003, 51 Pages, 2022/09

JAEA-Testing-2022-003.pdf:5.24MB
JAEA-Testing-2022-003-appendix(CD-ROM).zip:1.12MB

Advancement of the evaluation technology of the magma activity range is essential as one of the technical issues related to volcanic and igneous activities in the evaluation of the long-term stability of the geological environment in the geological disposal of high-level radioactive waste. As an effective method, topographical analysis of volcanic edifices is expected to be used to determine the distribution area of dikes. In recent years, the development of computer-based topographic analysis technology has made it possible to simply perform a large volume of work that would otherwise be difficult due to the manual handling. This report describes an analysis method for the shape of contour lines that forms volcanic edifices using GIS software.

Conceptual study on parasitic low-energy RI beam production with in-flight separator BigRIPS and the first stopping examination for high-energy RI beams in the parasitic gas cell

Sonoda, Tetsu*; Katayama, Ichiro*; Wada, Michiharu*; Iimura, Hideki; Sonnenschein, V.*; Iimura, Shun*; Takamine, Aiko*; Rosenbusch, M.*; Kojima, Takao*; Ahn, D. S.*; et al.

Progress of Theoretical and Experimental Physics (Internet), 2019(11), p.113D02_1 - 113D02_12, 2019/11

AA2019-0315.pdf:1.37MB

https://doi.org/10.1093/ptep/ptz120

An in-flight separator, BigRIPS, at RIBF in RIKEN provides each experiment with specific nuclides separated from many nuclides produced by projectile fragmentation or in-flight fission. In this process, nuclides other than separated ones are discarded on the slits in BigRIPS, although they include many nuclides interested from the view point of nuclear structure. In order to extract these nuclides for parasitic experiments, we are developing a method using laser ion-source (PALIS). A test experiment with Se beam from RIBF has been performed by using a gas cell set in BigRIPS. Unstable nuclides around Se were stopped in the gas cell in accordance with a calculation using LISE code. The stopping efficiency has been estimated to be about 30%. As a next step, we will establish the technique for extracting reaction products from the gas cell.

New muonium HFS measurements at J-PARC/MUSE

Strasser, P.*; Aoki, Masaharu*; Fukao, Yoshinori*; Higashi, Yoshitaka*; Higuchi, Takashi*; Iinuma, Hiromi*; Ikedo, Yutaka*; Ishida, Katsuhiko*; Ito, Takashi; Iwasaki, Masahiko*; et al.

Hyperfine Interactions, 237(1), p.124_1 - 124_9, 2016/12

https://doi.org/10.1007/s10751-016-1331-4

Development status of control system for IFMIF/EVEDA prototype accelerator

Takahashi, Hiroki; Narita, Takahiro; Nishiyama, Koichi; Usami, Hiroki; Sakaki, Hironao; Kasugai, Atsushi; Kojima, Toshiyuki*

Proceedings of 11th Annual Meeting of Particle Accelerator Society of Japan (Internet), p.799 - 802, 2014/10

http://www.pasj.jp/web_publish/pasj2014/proceedings/PDF/SAP1/SAP103.pdf

no abstracts in English

-ray and neutron area monitoring system of linear IFMIF prototype accelerator building

Takahashi, Hiroki; Kojima, Toshiyuki; Narita, Takahiro; Tsutsumi, Kazuyoshi; Maebara, Sunao; Sakaki, Hironao; Nishiyama, Koichi

Fusion Engineering and Design, 88(9-10), p.2736 - 2739, 2013/10

https://doi.org/10.1016/j.fusengdes.2013.04.007

For radiation safety of the Linear IFMIF Prototype Accelerator, -ray and neutron area monitoring system are designed. This system monitors and records the measured data by using both a supervisory board in the access room and central control system. The interlock signals are sent to Personnel Protection System (PPS) and Machine Protection System (MPS) when the integrated dose value exceeds a threshold value. After receiving them, the PPS and the MPS immediately inhibit the beam operation for secure radiation safety. This monitoring system is designed to achieve a high reliability for data transfer using hardwired interlock signals and the performance of data communication between area monitoring system and control system.

Molecular and carbon isotope compositions of hydrocarbon gas in Neogene sedimentary rocks in Horonobe area, northern Hokkaido, Japan

Funaki, Hironori; Ishiyama, Koji*; Waseda, Amane*; Kato, Susumu*; Watanabe, Kunio*

Chigaku Zasshi, 121(6), p.929 - 945, 2012/12

https://doi.org/10.5026/jgeography.121.929

Molecular and carbon isotope compositions of hydrocarbon gas have information related to their generation, migration and accumulation, and serve evaluations of gas permeability in sedimentary rocks. We conducted headspace gas analysis at the cores (below 500 m depth) to evaluate gas permeability in Neogene sedimentary rocks in the Horonobe, Hokkaido, Japan. As a result, it was shown that hydrocarbon gases were almost biogenic methane. Further analysis of these data indicated that concentration and carbon isotope of methane varied carbon isotopic fractionation during anaerobic microbial oxidation and migration near the faults. A formation of high concentration and light carbon isotope of methane at present in the study area is low gas permeability and is less affected by secondary post-generic process.