Alteration of stress field brought about by the occurrence of the 2011 off the Pacific coast of Tohoku Earthquake (M w 9.0)

Hiratsuka, Shinya; Sato, Tamao

doi:10.5047/eps.2011.05.013

Cited by 16 publications

(9 citation statements)

References 10 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Several authors have evaluated the Coulomb stress change due to the rupture of the 2011 Tohoku Earthquake (Hiratsuka and Sato, 2011;Lay et al, 2011;Toda et al, 2011). For a thrust fault with the same geometry as the mainshock, the expected areas of increased seismicity are located around both edges in the strike direction of the mainshock fault and the area of outer rise.…”

Section: Discussionmentioning

confidence: 99%

Seismic activity around the northern neighbor of the 2011 off the Pacific coast of Tohoku Earthquake with emphasis on a potentially large aftershock in the area

Kosuga

Watanabe

2011

Earth Planet Sp

View full text Add to dashboard Cite

We investigated the seismic activity around the northern neighbor of the 2011 off the Pacific coast of Tohoku Earthquake (M W 9.0) with special attention to a potential large aftershock in the area. We obtained a combined data set by adding our manually-picked locations to the catalog locations by the Japan Meteorological Agency. The hypocenter distribution delineates active and inactive bands of seismicity. The band of low seismicity corresponds to a zone of a large seismic slip, indicating that aftershocks occurred in peripheral neighbors of the mainshock asperity. The broad band of active seismicity along the coast corresponds to the zone of a large postseismic slip, suggesting the enhancement of the aftershock activity by the slip. Although the northern neighbor of the mainshock fault is a favored region of increased seismicity, as shown from a Coulomb stress calculation, no significant seismic activity is observed within the potential source area except along the Japan Trench and the SW corner. This implies that the zone of interplate moment release by previous large earthquakes and the subsequent slow slip acted as a barrier to the migration of both the mainshock rupture and aftershock activity. However, an aftershock area in the zone may reflect inhomogeneous moment release by past seismic and aseismic sequences.

show abstract

Section: Discussionmentioning

confidence: 99%

Seismic activity around the northern neighbor of the 2011 off the Pacific coast of Tohoku Earthquake with emphasis on a potentially large aftershock in the area

Kosuga

Watanabe

2011

Earth Planet Sp

View full text Add to dashboard Cite

show abstract

“…shows a map view of the deviatoric minimum stress (hereafter referred to as “extensional stress”) at a depth of 8 km; it indicates that an extensional stress of up to 1 MPa was induced at the target area. Although the induced extensional stress clearly favors the activation of normal‐fault earthquakes [ Hiratsuka and Sato , 2011; Toda et al , 2011], a key question is whether the induced stress could overcome a pre‐existing compressional reverse stress state. Much of the data obtained from deep boreholes suggest that an appropriate reference stress state for an intraplate continental upper crust is governed by optimally oriented, cohesionless faults under the conditions of hydrostatic pore pressure and Byerlees's friction law [e.g., Townend , 2006].…”

Section: Stress Transferred By the 2011 Tohoku Earthquakementioning

confidence: 99%

Unusual shallow normal‐faulting earthquake sequence in compressional northeast Japan activated after the 2011 off the Pacific coast of Tohoku earthquake

Imanishi

Ando

Kuwahara

2012

Geophysical Research Letters

View full text Add to dashboard Cite

After the occurrence of the 2011 Mw9.0 off the Pacific coast of Tohoku earthquake, an unusual shallow normal‐faulting earthquake sequence occurred near the Pacific coast at the Ibaraki‐Fukushima prefectural border. We have investigated why normal‐faulting earthquakes were activated in northeast (NE) Japan, which is otherwise characterized by E–W compression. We computed the stress changes associated with the mainshock on the basis of a finite fault slip model, which showed that the amount of additional E–W tensional stresses in the study area was up to 1 MPa, which might be too small to generate normal‐faulting earthquakes in the pre‐shock compressional stress regime. We thus determined focal mechanisms of microearthquakes that occurred in the area before the mainshock, which indicated that the pre‐shock stress field in the area showed a normal‐faulting stress regime in contrast to the overall reverse‐faulting regime in NE Japan. We concluded that the 2011 Tohoku earthquake triggered the normal‐faulting earthquake sequence in a limited area in combination with a locally formed pre‐shock normal‐faulting stress regime. We also explored possible mechanisms for localization of a normal‐faulting stress field at the Ibaraki‐Fukushima prefectural border.

show abstract

“…The March 11, 2011 Mw 9.0 Tohoku‐oki earthquake is the fourth largest event to occur in the past century. The tsunami wave generated by this earthquake had a maximum wave height between 10 and 20 m [ Hiratsuka and Sato , 2011], devastating regions along the northeastern coast of Honshu, Japan. Initial results show that horizontal displacements measured on the seafloor near the epicenter reach values of 24 m [ Sato et al , 2011].…”

Section: Introductionmentioning

confidence: 99%

The March 11, 2011 Tohoku‐oki earthquake and cascading failure of the plate interface

Kiser

Ishii

2012

Geophysical Research Letters

View full text Add to dashboard Cite

A continuous back‐projection analysis using data recorded in North America between March 9, 2011 and April 7, 2011 is applied to the Mw 9.0 2011 Tohoku‐oki earthquake and the foreshocks and aftershocks of this event. As with the Mw 8.8 2010 Maule, Chile earthquake, back‐projection results of the mainshock show variations in rupture behavior when data filtered to different frequency ranges are used. In particular, there is a relationship between the frequency of data used and the position along the dip direction of the energy release, with the highest‐frequency result imaging energy at the down‐dip edge of the rupture and progressively lower frequencies showing a continuous shift updip. In addition, these results show that late in the rupture (∼200 seconds after the hypocentral time), energy at all frequencies is imaged very close to the trench at about 37°N, which, with the energy imaged near and updip of the epicenter, may have acted as a tsunami source. Comparing the mainshock rupture area to the area that ruptured during M ≥ 6 foreshocks and aftershocks between March 9th and April 7th shows that total failure of the plate interface nearly doubled compared to the mainshock alone. Building upon the idea that the mainshock occurred through interactions between multiple segments, the results imply that the total failure area of the interface may represent the area that can rupture during a single event as a series of in‐phase interface segments.

show abstract

Alteration of stress field brought about by the occurrence of the 2011 off the Pacific coast of Tohoku Earthquake (M w 9.0)

Cited by 16 publications

References 10 publications

Seismic activity around the northern neighbor of the 2011 off the Pacific coast of Tohoku Earthquake with emphasis on a potentially large aftershock in the area

Seismic activity around the northern neighbor of the 2011 off the Pacific coast of Tohoku Earthquake with emphasis on a potentially large aftershock in the area

Unusual shallow normal‐faulting earthquake sequence in compressional northeast Japan activated after the 2011 off the Pacific coast of Tohoku earthquake

The March 11, 2011 Tohoku‐oki earthquake and cascading failure of the plate interface

Contact Info

Product

Resources

About