東京大学地震研究所
Earthquake Research Institute, the University of Tokyo
山形大学教育学部
Faculty of Education, Yamagata University
東京大学大学院理学系研究科
Graduate School of Science, the University of Tokyo
山梨大学教育人間科学部
Faculty ofEducation and Human Sciences, Yamanashi University
千葉大学理学部
Department of Earth Science, Chiba University
愛知教育大学
Aichi University of Education
東北大学大学院理学研究科
Graduate School of Science, Tohoku University
千葉大学大学院理学系研究科
Graduate School of Science and Technology, Chiba University
（株）地球科学総合研究所
Japex Geoscience Institute Inc.
動力炉・核燃料開発事業団・東農地地球科学センター
Tono Geoscience Center, Power Reactor and Nuclear Fuel Development Corporation
抄録
Late Quaternary, active folds are well developed in the eastern part of the Shinjo Basin, central northern Honshu, Japan. To reveal the geometry of the folds, seismic reflection profiling was undertaken across the NS-trending folds in the eastern Shinjo Basin. The total length of the seismic line is about 14 km. The seismic source was amini-vibrator truck with 30 seconds of 10-80 Hz signals at 30m intervals. The signal was recorded on 120 and 180 channels by a 15-m group interval of 10 3Hz geophones. The seismic reflection profiles portray the style of folds down to 1.5km in depth. The Neogene basin fill forms asynmetrical fault-related folds associated with an east dipping reverse fault on their western flanks. The range boundary fault (Kyodanbara fault) is demonstrated in the seismic section as an east dipping reverse fault at about 40℃. Based on the fold geometry and prevailing bedding slip, it is interpreted that the Tominami anticline was formed by flexural-slip folding, and the competent layer was a Pliocene sandstone unit. No obvious growth strata are recognized in the seismic sections, suggesting that the main phase of folding and faulting occurred after deposition of the Dokuzawa Formation.
雑誌名
東京大學地震研究所彙報 = Bulletin of the Earthquake Research Institute, University of Tokyo
巻
81
号
2
ページ
157 - 169
発行年
2006
ISSN
00408972
書誌レコードID
AN00162258
フォーマット
application/pdf
日本十進分類法
051.1
出版者
東京大学地震研究所
出版者別名
Earthquake Research Institute, University of Tokyo
新庄盆地東部活褶曲群を横切る反射法地震探査
IHO81208.pdf
(13.9MB)
