Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Goto, Akira; Sasaki, Akimichi*; Komatsu, Tetsuya; Miwa, Atsushi*; Terusawa, Shuji*; Kagohara, Kyoko*; Shimada, Koji
JAEA-Research 2020-013, 88 Pages, 2020/11
JAEA-Research-2020-013.pdf:22.86MB
JAEA-Research-2020-013-appendix(CD-ROM).zip:0.18MB
Improvement of the investigation techniques to identify active faults is important for the implementation of geological disposal projects from the viewpoint of avoiding locations where permeability increases due to fault displacement. Generally, the existence of active faults is confirmed by aerial photography interpretation of fault displacement topography, which is a topographical trace of fault movement, and on-site geological surveys. However, the investigation method for cases where the topographical traces are unclear is not sufficiently developed. Therefore, to improve existing topographical methods, this study deciphered lineaments up to the rank of poorly defined features, which are almost neglected in general active fault research. The investigation area is one of the geodetic strain concentration zone, called the southern Kyushu shear zone, where the seismogenic faults of the 1997 Kagoshima northwest earthquakes are concealed. We conducted aerial photography interpretation of 62 sheets of 1/25,000 topographic maps, and obtained 1,327 lineaments. Distribution density, direction and length of lineaments were also investigated with topographic and geologic information. As a result, it was clarified that the east-west lineaments in the south Kyushu shear zone predominate in the western part, and the lineaments are densely distributed in the aftershock distribution area of the Kagoshima northwest earthquake. Along with these results, we have compiled a catalog of typical 13 lineaments based on combinations of clarity, direction, length and geomorphic characters of lineaments.
*; *; Fukumura, H.*; *; Nishii, Masanobu; Ichinose, Yuji; Kawanishi, Shunichi
Reza Kenkyu, 25(4), p.306 - 311, 1997/04
no abstracts in English
; ; ; ; *; *
J.Oceanogr.Sci.Jpn., 40, p.98 - 104, 1984/00
no abstracts in English
Kawamura, Shunsuke; Naoe, Takashi; Tanaka, Nobuatsu*; Futakawa, Masatoshi
no journal, ,
In the mercury target for the pulsed spallation neutron source at J-PARC, cavitation damage at the beam window of the mercury target vessel is a key factor to decide lifetime of target because the damage degrade the vessel structural integrity. A double-walled structure with a narrow channel was adopted to the vessel for expecting to reduce cavitation damage. In this study, the cavitation bubble behaviors of the growth and collapse under water flow field were investigated to determine the effective factor for mitigating cavitation damage in narrow channel. We measured the equivalent diameter and wall vibration due to the cavitation bubble collapse with parametrically changing flow velocity. It was found that the maximum equivalent diameter of the cavitation bubble and the response vibrational acceleration of the wall are decreased with the increasing velocity. As the results, it was found that cavitation bubble collapse pressure was affected by flowing condition in the narrow channel.
