DOI: 10.1002/grl.50104
论文题名: Imaging the source regions of normal faulting sequences induced by the 2011 M9.0 Tohoku-Oki earthquake
作者: Kato A. ; Igarashi T. ; Obara K. ; Sakai S. ; Takeda T. ; Saiga A. ; Iidaka T. ; Iwasaki T. ; Hirata N. ; Goto K. ; Miyamachi H. ; Matsushima T. ; Kubo A. ; Katao H. ; Yamanaka Y. ; Terakawa T. ; Nakamichi H. ; Okuda T. ; Horikawa S. ; Tsumura N. ; Umino N. ; Okada T. ; Kosuga M. ; Takahashi H. ; Yamada T.
刊名: Geophysical Research Letters
ISSN: 0094-9357
EISSN: 1944-9088
出版年: 2013
卷: 40, 期: 2 起始页码: 273
结束页码: 278
语种: 英语
Scopus关键词: 2011 Tohoku-Oki earthquakes
; High-resolution models
; Hypocenter location
; Ibaraki prefecture
; Low-velocity anomaly
; Spatiotemporal evolution
; Structural failure
; Tohoku-Oki earthquakes
; Faulting
; Fracture mechanics
; Earthquakes
; aftershock
; crustal structure
; earthquake magnitude
; faulting
; seismic source
; seismicity
; slip rate
; spatiotemporal analysis
; Tohoku earthquake 2011
; Fukushima
; Honshu
; Ibaraki
; Japan
; Kanto
; Tohoku
英文摘要: Intense swarm-like seismicity associated with shallow normal faulting was induced in Ibaraki and Fukushima prefectures, Japan, following the 2011 Tohoku-Oki earthquake. This seismicity shows a systematic spatiotemporal evolution, but little is known of the heterogeneity in crustal structure in this region, or its influence on the evolution of the seismicity. Here, we elucidate a high-resolution model of crustal structure in this region and determine precise hypocenter locations. Hypocenters in Ibaraki Prefecture reveal a planar earthquake alignment dipping SW at ∼45°, whereas those in Fukushima Prefecture show a more complex distribution, consisting of conjugate sets of aligned small earthquakes. On the north of the hypocenter of the largest earthquake in the sequence (the M7.0 Iwaki earthquake), we imaged a high-velocity body at shallow depths that lacks aftershock seismicity. Based on fault source models, the large-slip region of the Iwaki earthquake is situated along a zone that roughly coincides with this high-velocity body. We delineated a separate low-velocity anomaly directly beneath the hypocenter of the Iwaki earthquake, indicating crustal fluids in this region. We hypothesize that strong crust underwent structural failure due to the infiltration of crustal fluids into the seismogenic zone from deeper levels, causing the Iwaki earthquake. © 2013. American Geophysical Union. All Rights Reserved. URL: https://www.scopus.com/inward/record.uri?eid=2-s2.0-84874916138&doi=10.1002%2fgrl.50104&partnerID=40&md5=44f655bc19509a937a4fb16bea6a7c7c
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资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/6621
Appears in Collections: 气候减缓与适应
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作者单位: Earthquake Research Institute, University of Tokyo, Tokyo, Japan
Recommended Citation:
Kato A.,Igarashi T.,Obara K.,et al. Imaging the source regions of normal faulting sequences induced by the 2011 M9.0 Tohoku-Oki earthquake[J]. Geophysical Research Letters,2013-01-01,40(2).