Improve long periodic ground motion evaluation with the epicenter on the border between Fukushima and Ibaraki prefectures in seismic design of nuclear facilities

Kirita, Fumio; Tominaga, Masahiro; Yamazaki, Toshihiko; Seshimo, Kazuyoshi; Uryu, Mitsuru

JAEA-Research 2022-006, 61 Pages, 2023/02

JAEA-Research-2022-006.pdf:6.24MB

Nuclear Fuel Cycle Engineering Laboratories (NCL) has been observing ground motion for a long time. On the border from northern Ibaraki prefecture to Fukushima prefecture, inland crustal earthquakes occur less frequently until the 2011 off the Pacific coast of Tohoku Earthquake (hereinafter referred to as Tohoku Earthquake). After Tohoku Earthquake, aftershocks have become more frequent in this area, and in the Hamadori region of Fukushima earthquake that a remarkable long periodic component was observed in the NCL seismic observation record. Until now there were no such things that long periodic components were observed at the observation points near the epicenter of April 2011 Fukushima earthquake, but it was thought basin structure in deep basement around the NCL affected the propagation process to NCL by reflection survey result. As basement structure of NCL affected the seismic wave propagation process, the seismic wave repeatedly reflects and refracts. For that reason, long periodic components of seismic waves may be possibly amplified. In this study, in order to refine the long periodic ground motion evaluation, using a three dimensional ground structure model (3D model) that can reflect the shape of the deep basement structure around the NCL. When modeling 3D ground structure which has a width of about 80km and a length of about 110km and ranges from the epicenter area of April 2011 Fukushima earthquake to the northern coastal area of Ibaraki prefecture modeled, improved the optimum ground structure model using multiple observation records and performed simulation analysis.

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.

A Sampling method of oriented small sample from fault cores for SEM observation

Shimada, Koji; Kametaka, Masao*; Nakayama, Kazuhiko; Seshimo, Kazuyoshi; Tanaka, Yoshihiro; Hayashi, Toshio*; Tanaka, Yukumo; Shimogama, Kota*; Okazaki, Kazuhiko*

Chishitsugaku Zasshi, 119(11), p.727 - 731, 2013/11

https://doi.org/10.5575/geosoc.2013.0050

Staples for a stapler can be used as a frame of a small oriented sample taken from fragile and scarce fault gouge. The fault gouge was slotted for staples of an insert. Staples are a group of about ten or less ones holding right-angled three small surfaces. Pre-oriented staples set the slot would remove then presented for the SEM observation. Only a knife, some glues and simple equipment are needed for the method in the field or laboratories.

Method of restoring forest by spraying black pine seeds in J-PARC

Yamanishi, Takeshi; Seshimo, Kazuyoshi; Kitami, Takayuki; Naruse, Hideo; Tan, Sakyo*

Nihon Ryokka Kogakkai-Shi, 30(1), p.227 - 230, 2004/08

https://doi.org/10.7211/jjsrt.30.227

Large-scale pine woods is deforested before the High-Intensity Proton Accelerator facilities construction in the Japan Atomic Energy Research Institute Tokai Research Establishment. Spraying the black pine seeds by spraying as an trial method of planting for the restoration of this forest.

Mechanical test for the determination of shear sense from experimentally deformed fault gouge samples

Kametaka, Masao*; Nakayama, Kazuhiko; Aoki, Kazuhiro; Seshimo, Kazuyoshi; Shimada, Koji; Tanaka, Yoshihiro; Okazaki, Kazuhiko*; Funato, Akio*; Hayashi, Toshio*

no journal, , 

no abstracts in English

Examination of evaluation method for fault activity based on an observation of fault zone; Selection of outcrops, in-situ experiments

Kametaka, Masao*; Okazaki, Kazuhiko*; Nakayama, Kazuhiko; Seshimo, Kazuyoshi; Aoki, Kazuhiro; Tanaka, Yoshihiro; Shimada, Koji; Suzuki, Kazushige*; Shimogama, Kota*; Inada, Noriyuki*

no journal, , 

The evaluation of an fault activity has been done by an observation of deformation of overlying strata of the fault. However, it is difficult to evaluate the activity where the fault zone appears only in a basement rock with no overlying strata. We have been carried out the observation of the fault zone to establish the method of evaluation of fault activity. We selected the outcrops through literature and surface geological survey. Examples of outcrops of active fault are outcrops of Gosukebashi Fault in the Rokko-Awaji Fault Zone and the Rokko Fault in the Arima-Takatsuki Tectonic Line, southern Hyogo Prefecture. An example of non-active fault is outcrop of the fault around the Rokko Horai-kyo in the northern Rokko Mountains. In this study, we focus on the easy evaluation method in the field, and described about suitability of observation of fault plane, in-situ experiments of hardness and color.

Frictional properties of Shionohira Fault Gouge

Aoki, Kazuhiro; Seshimo, Kazuyoshi; Tanaka, Yoshihiro; Kametaka, Masao*; Sakai, Toru*; Okazaki, Kazuhiko*; Shimamoto, Toshihiko*

no journal, , 

no abstracts in English

The Property of fault zone and sense of displacement on the Shionohira Fault, Fukushima Prefecture, Japan

Sakai, Toru*; Kametaka, Masao*; Tanaka, Yumiko*; Aoki, Kazuhiro; Tanaka, Yoshihiro; Niwa, Masakazu; Seshimo, Kazuyoshi

no journal, , 

no abstracts in English

Frictional properties of Shionohira Fault Gouge, 2; A Comparison with Kuruma Fault Gouge at the southern extension of Shionohira Fault

Aoki, Kazuhiro; Seshimo, Kazuyoshi; Tanaka, Yoshihiro*; Niwa, Masakazu; Masuda, Yuki; Kametaka, Masao*; Sakai, Toru*; Shimamoto, Toshihiko*

no journal, , 

no abstracts in English

Frictional properties of Main Fault Gouge of Mont Terri, Switzerland

Aoki, Kazuhiro; Seshimo, Kazuyoshi; Guglielmi, Y.*; Nussbaum, C.*; Shimamoto, Toshihiko*; Ma, S.*; Yao, L.*; Kametaka, Masao*; Sakai, Toru*

no journal, ,