Newly found fault outcrops of the Tsuruga fault in the Mihama Town, Fukui Prefecture, Japan

Tateishi, Ryo*; Shimada, Koji; Iwamori, Akiyuki*; Wada, Shinya*; Seno, Shotaro*; Nagata, Ken*

Chishitsugaku Zasshi (Internet), 128(1), p.63 - 64, 2022/04

https://doi.org/10.5575/geosoc.2022.0007

The Tsuruga Fault is an active right-lateral strike-slip fault that is about 20 km in length and distributed in the northeast-southwest direction from the eastern part of Tsuruga City to the southern part of Mihama Town, Fukui Prefecture. The Tsuruga fault borders the Jurassic accretionary complex (mixed rock) and the late Cretaceous granite around the Oritodani area in the Shinjo district of Mihama-cho. Lateral bendings of valleys along the fault in this area are clear geomorphological signatures of fault activity. We briefly report newly found multiple fault outcrops at these bending points with photos of them. This research is the result of joint research by Kansai Electric Power Company, University of Toyama, and JAEA.

Characteristics of fault fracture zones of the activated Shionohira Fault and the non-activated Kuruma Fault of the 2011 Fukushima-ken Hamadori Earthquake, Northeast Japan

Aoki, Kazuhiro; Tanaka, Yukumo; Yoshida, Takumi; Shimada, Koji; Sakai, Toru*; Kametaka, Masao*; Seshimo, Kazuyoshi

Oyo Chishitsu, 62(2), p.64 - 81, 2021/06

Co-seismic surface ruptures in the Fukushima-ken Hamadori Earthquake of Mw 6.7 on April 11, 2011 exposed approximately 14 km trending NNW-SSE from Nameishi to northwest of Ishizumi Tsunaki of Tabito Town, Iwaki City and were newly named the Shionohira Fault. However, no surface ruptures appeared along an N-S trending active Kuruma fault extending 5 km south of the Shionohira Fault. Because of the proximity and similar strike, two locations in Shionohira Fault and one location in Kuruma fault were selected as the study area for the fault activity evaluation. The present study reports the results of a series of geological and drilling surveys, core observation, XRD, isotope, and fluid inclusion analyses, and water permeability test. The results obtained from the three locations offer a fundamental data base that can be utilized for fault activity evaluation by summarizing the geological, mineralogical, and fluid property characteristics of fault fracture zone.

Discrete fracture network model for faults distributed in Neogene massive siliceous mudstones

Hayano, Akira; Ishii, Eiichi

Shigen, Sozai Koenshu (Internet), 5(1), 9 Pages, 2018/03

no abstracts in English

User's manual of a computer code for Seismic Hazard Evaluation for Assessing the Threat to a facility by Fault Model; SHEAT-FM

Sugino, Hideharu*; Onizawa, Kunio; Suzuki, Masahide

JAERI-Data/Code 2005-008, 95 Pages, 2005/09

JAERI-Data-Code-2005-008.pdf:3.46MB

To establish the reliability evaluation method for aged structural component, we developed a probabilistic seismic hazard evaluation code SHEAT-FM (Seismic Hazard Evaluation for Assessing the Threat to a facility site; Fault Model) using a seismic motion prediction method based on fault model. In order to improve the seismic hazard evaluation, this code takes the latest knowledge in the field of earthquake engineering into account. For example, the code involves a group delay time of observed records and an update process model of active fault. This report describes the user's guide of SHEAT-FM, including the outline of the seismic hazard evaluation, specification of input data, sample problem for a model site, system information and execution method.

The Primary evaluation of the impacts of naturaI phenomena on the safety functions of the geological disposal system; An Example study on site generic phase

Makino, Hitoshi; ; Miyahara, Kaname

JNC TN8400 2000-033, 74 Pages, 2000/11

JNC-TN8400-2000-033.pdf:9.19MB

Natural phenomena is one of the potential factors perturbing the long-term stability of the geological environment, and for natural phenomena, it is necessary to consider uncertainties relevant to time, frequency and effect. Therefore it will be important to have information about the potential impacts of natural phenomena on the safety functions of geological disposal system in the future by assuming that natural phenomena perturbs the safety functions of the geological disposal system. In this report, we have considered 4 natural phenomena, 'uplift, subsidence and denudation', 'climatic and sea-level changes', 'earthquakes and fault movement' and 'volcanism', which had been extracted by investigation in foreign countries and by considering the characteristics of Japan as natural phenomena which may perturb the long-term stability of the geological environment. And we have considered mainly typical effects of naturaI phenomena on geological environment and investigated the typical impacts of those natural phenomena on the safety functions of the geological disposal system. On perturbation scenarios, the maximum of total doses have been less than regulatory guidelines in foreign countries in all situations except the cases assuming that a new fault, which causes significant pathway of groundwater flow and nuclide migration, intersects the waste packages. In the case, the maximum of total doses may reach the same level as regulatory guidelines in foreign countries or natural radiation exposure in Japan depending on fault generation time or grandwater flow rate through the fault. And, on isolation failure scenarios, it has been implied that nuclide mass/flux originated from geological disposal is comparable level with nuclide mass/flux in natural environment. These results could give useful information about the potential impacts of natural phenomena on the safety functions of geological disposal system, and also could show the potential importance of ...

None

; Hama, Katsuhiro; ; Saito, Hiroshi;

JNC TN7410 2000-004, 16 Pages, 2000/04

JNC-TN7410-2000-004.pdf:0.5MB

Macroscopically and microscopically research about structure of faults at a repository scale

*; *; Morooka, Koichi*

JNC TJ8400 2000-043, 170 Pages, 2000/03

JNC-TJ8400-2000-043.pdf:7.63MB

This study is an object to collect and arrange data about the mass transfer path during a natural barrier system by grasping actual rock feature, in order to be useful for a performance assessment of a natural barrier system at geological disposal of HLW. An existence of permeability high large-scale faults extends a large influence over a performance assessment of geological disposal. With "The Second Progress Report on Research and Development for the Geological Disposal of HLW in Japan" which Nuclear Cycle Development Institute (JNC) issued, it is as" A repository would be located at least 100 meters away from major faults and major fracture zones which could adversely affect the stability and performance of the repository" as a Reference Case concept model of a natural barrier system, Then, they are as "in the Reference Case, the transport path consists of the host rock and the downstream fault". It will not be easy to know the distribution of faults in the subsurface deep division without data acquired from many boreholes and underground laboratory. With this study, specific data on the large-scale faults and fracture zones has been collected and arranged by investigating in underground galleries and on the literatures of a post-operated mine site. Based on this result, a consideration on the principal transfer pass at a natural barrier system has been conducted. The contents conducted in this report is the follows. (1)investigation of literature about data of fracture, shear zone, and geology, (2)field investigation of fracture and shear zone in the rock, (3)arrangement of these results, (4)modeling of the major water conductive feature, and (5)evaluation of an assumption which has been introduced in the Second Progress Report issued by JNC.

None

*; Aizawa, Takao*; *

JNC TJ7420 2000-006, 54 Pages, 2000/03

JNC-TJ7420-2000-006.pdf:16.6MB

no abstracts in English

Development of advanced neutron radiography for inspection on irradiated fuels and materials; Feasibility study of neutron radiography in terms of PIE execution

Yasuda, Ryo; Nishi, Masahiro; Nakata, Masahito; Matsubayashi, Masahito

JAERI-Tech 2000-030, p.20 - 0, 2000/03

JAERI-Tech-2000-030.pdf:2.2MB

no abstracts in English

Working Programme for MIU-4 Borehole Investigations

Ota, Kunio; Nakano, Katsushi; Metcalfe, R.; Ikeda, Koki; ; Amano, Kenji; Takeuchi, Shinji; Hama, Katsuhiro; Matsui, Hiroya

JNC TN7410 99-007, 44 Pages, 1999/08

JNC-TN7410-99-007.pdf:2.59MB