2024-03-28T12:55:44Z
https://repository.dl.itc.u-tokyo.ac.jp/oai
oai:repository.dl.itc.u-tokyo.ac.jp:00032484
2022-12-19T05:37:54Z
80:4535:4587:4595
9:504:4538:4589:4596
Seismic Reflection Profiling Across the North of the Itoigawa-Shizuoka Tectonic Line in Omachi, Central Japan
糸魚川-静岡構造線活断層系北部大町地域の浅層反射法地震探査
松多, 信尚
124404
池田, 安隆
124405
佐藤, 比呂志
124406
今泉, 俊文
124407
田力, 正好
124408
蔵下, 英司
124409
河村, 知徳
124410
加藤, 直子
124411
戸田, 茂
124412
谷, 美由起
124413
加藤, 一
124414
東郷, 正美
124415
中村, 洋介
124416
越後, 智雄
124417
田中, 淳彦
124418
井川, 猛
124419
大町反射法地震探査グループ
124420
51.1
Itoigawa-Shizuoka Tectonic line
seismic reflection profiling
Omine Formation
thrust front migration
Eastern Matsumoto Basin fault
application/pdf
The Itoigawa-Shizuoka tectonic line (ISTL) active fault system poses the highest seismic risk, and shows one of the largest slip rates among active faults on Honshu Island. In the Omachi area, the ISTL active fault system comprises the eastern Matsumoto basin (EMB) fault to the west and the Otari-Nakayama fault to the east. To understand the structural relation between these two faults, we conducted a seismic reflection survey across them. The length of the seismic line is 6.4km, and the receiver and shot point intervals are 10m. We used a mini-vibrator as a seismic source with a 180-channel seismic recording system. We can image the structure to less than about 1km in depth. The seismic depth section displays the EMB fault as a boundary between east-dipping reflectors to the east and horizontal reflectors in the Masumoto basin. The EMB fault is interpreted as an east vergent, emergent thrust, and its deeper extension merges with the Otari-Nakayama fault. The Omine Formation, which was laid down on an alluvial fan in the late Pliocene and the early Pleistocene, is distributed between EMB and Otari-Nakayama fault. It is evident that the thrust front migrated from the Otari-Nakaya fault to the EMB fault in Quaternary, and then the Omine Formation located at the foreland basin was uplifted.
departmental bulletin paper
地震研究所
2007
application/pdf
地震研究所彙報
1
82
37
44
AN00162258
00408972
https://repository.dl.itc.u-tokyo.ac.jp/record/32484/files/IHO82105.pdf
jpn