A detailed source model for the Mw9.0 Tohoku‐Oki earthquake reconciling geodesy, seismology, and tsunami records

Blétery, Quentin; Sladen, Anthony; Delouis, Bertrand; Vallée, Martin; Nocquet, Jean‐Mathieu; Rolland, Lucie; Jiang, Junle

doi:10.1002/2014jb011261

Cited by 72 publications

(82 citation statements)

References 88 publications

(140 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Under the free boundary condition, which allows the slip to reach the free surface, our preferred model showed that the greatest slip occurred up-dip of the hypocenter near the trench. This result is in agreement with that of other works (Lee et al 2011;Suzuki et al 2011;Bletery et al 2014), although the amplitudes are inconsistent.…”

Section: Discussionsupporting

confidence: 93%

“…The maximum model slip was ~65 m, which is slightly larger than the 25-60 m in most previous results based on seismic waveform, geodetic, and tsunami data (Ozawa et al 2011;Simons et al 2011;Koketsu et al 2011;Yokota et al 2011;Saito et al 2011;Suzuki et al 2011;Lee et al 2011;Zhou et al 2014) and approaches that of 64 m obtained by Bletery et al (2014). The main rupture area spans ~400 km along the strike and ~200 km along the dip.…”

Section: Discussionmentioning

confidence: 50%

“…Using hr-GPS data in single inversion or joint inversion with other available data Bletery et al 2014) for the rupture process has been performed with a constant rupture velocity to obtain a consistent main slip asperity with a simple rupture feature up-dip of the hypocenter to the trench. A rupture model with freely varying rupture velocity for each subfault has been presented by Minson et al (2014) from joint inversion of geodetic data and tsunami data using a single-time-window method.…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Source process with heterogeneous rupture velocity for the 2011 Tohoku-Oki earthquake based on 1-Hz GPS data

Wang

Kato

Xiao-hong

et al. 2016

Earth Planets Space

View full text Add to dashboard Cite

Abstract:A rupture model with varying rupture front expansion velocity for the March 11, 2011, Tohoku-Oki earthquake was obtained by the joint inversion of high-rate Global Positioning System (GPS) data and ocean bottom GPS/acoustic (OB-GPS) data. The inverted rupture velocity with a complex distribution gradually increases near the hypocenter and shows rapid rupture expansion at the shallowest part of the fault. The entire rupture process, which lasted 160 s, can be divided into three energy release stages, based on the moment rate function. The preferred slip model, showing a compatible relationship with aftershocks, has a primary asperity concentrated from the hypocenter to the trench and a small asperity located on the southern fault. Source time functions for subfaults and temporal rupture images suggest that repeated slips occurred in the primary rupture, which is consistent with that from seismic waveforms. Our estimated maximum slip and total seismic moment are ~65 m and 4.2 × 10 22 Nm (Mw 9.0), respectively. The large slip, stress drop, and rupture velocity are all concentrated at shallow depths, which indicates that the shallow part of the fault radiated high-frequency as well as low-frequency seismic waves.

show abstract

Section: Discussionsupporting

confidence: 93%

Section: Discussionmentioning

confidence: 50%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Source process with heterogeneous rupture velocity for the 2011 Tohoku-Oki earthquake based on 1-Hz GPS data

Wang

Kato

Xiao-hong

et al. 2016

Earth Planets Space

View full text Add to dashboard Cite

show abstract

“…The coseismic slip distribution extended approximately 400 km along the Japan trench, with a maximum slip ranging between 27 m (Ozawa et al 2011) and 80 m (Iinuma et al 2012). The data reveal a compact area of large slip, extending from the trench to about 50 km of depth (Bletery et al 2014). Afterslip was mostly distributed in an area located downdip of the coseismic slip and extending to a depth of about 100 km (Lay et al 2012;Silverii et al 2014).…”

Section: An Application: the 2011 Tohoku-oki Earthquakementioning

confidence: 85%

Dynamics of a fault model with two mechanically different regions

Dragoni

Lorenzano

2017

Earth Planets Space

View full text Add to dashboard Cite

We consider a fault containing two regions with different mechanical behaviours: a strong, velocity-weakening region (asperity) and a weak, velocity-strengthening region. The fault is embedded in a shear zone subject to a constant strain rate by the motions of adjacent tectonic plates. The fault is modelled as a discrete dynamical system whose state is described by two variables expressing the slip deficits of the two regions. Because of plate motion, the asperity accumulates stress and eventually releases it, producing an earthquake, when a frictional threshold is exceeded. The weak region is subject to a very slow creep during interseismic intervals and may slip at a higher rate (afterslip) as a consequence of coseismic stress imposed by the asperity failure. The evolution equations of the system are solved analytically for the interseismic intervals, the asperity slip and the afterslip in the weak region. It is found that the amount of afterslip is proportional to the seismic slip of the asperity, in agreement with observations. The model shows that afterslip is a natural consequence of seismic slip in a fault containing a velocity-strengthening region. Afterslip may have any duration, according to the intensity of velocity strengthening, thus accounting for the wide range of observed durations. The model is applied to the fault of the 2011 Tohoku-Oki earthquake. The results suggest that the first four months after the event were dominated by afterslip, while the subsequent postseismic deformation was probably due to viscoelastic relaxation in the asthenosphere.

show abstract

“…Efforts are under way to synthesize the accumulated data sets (e.g., Kanamori, 2014;Lay, 2015;Ye et al, 2016bYe et al, , 2016cDenolle and Shearer, 2016;Meier et al, 2017;Melgar and Hayes, 2017;Hayes, 2017), and we will not attempt to summarize the multitude of studies. Large shallow coseismic slip occurred in the 2015 Illapel (e.g., Li et al, 2016;Melgar et al, 2016), 2011 Tohoku (e.g., Lay et al, 2011b;Iinuma et al, 2012;Ozawa et al, 2012;Satake et al, 2013;Romano et al, 2014;Bletery et al, 2014;Melgar and Bock, 2015;Lay, 2017), 2010 Maule (e.g., Vigny et al, 2011;Yue et al, 2014b;Yoshimoto et al, 2016;Maksymowicz, et al, 2017), and 2004 Sumatra (e.g., Ammon et al, 2005;Rhie et al, 2007;Fujii and Satake, 2007) events, accompanying slip on the downdip portions of the megathrusts. In other cases, such as the 2014 Iquique, Chile (e.g., Lay et al, 2014;Hayes et al, 2014b), 2012 Nicoya, Costa Rica (e.g., Yue et al, 2013;Liu et al, 2015), 2003 Tokachi-oki, Japan (e.g., Miyazaki and Larson, 2008;Romano et al, 2010), and 2007 Pisco, Peru, ruptures (e.g., Lay et al, 2010a;Sladen et al, 2010), slip was concentrated on the central or deeper portion of the rupture zone, with no shallow coseismic slip.…”

Section: Spatial Variations Of Slipmentioning

confidence: 99%

Subduction zone megathrust earthquakes

2018

View full text Add to dashboard Cite

Subduction zone megathrust faults host Earth's largest earthquakes, along with multitudes of smaller events that contribute to plate convergence. An understanding of the faulting behavior of megathrusts is central to seismic and tsunami hazard assessment around subduction zone margins. Cumulative sliding displacement across each megathrust, which extends from the trench to the downdip transition to interplate ductile deformation, is accommodated by a combination of rapid stick-slip earthquakes, episodic slow-slip events, and quasi-static creep. Megathrust faults have heterogeneous frictional properties that contribute to earthquake diversity, which is considered here in terms of regional variations in maximum recorded magnitudes, Gutenberg-Richter b values, earthquake productivity, and cumulative seismic moment depth distributions for the major subduction zones. Great earthquakes on megathrusts occur in irregular cycles of interseismic strain accumulation, foreshock activity, main-shock rupture, postseismic slip, viscoelastic relaxation, and fault healing, with all stages now being captured by geophysical monitoring. Observations of depth-dependent radiation characteristics, large earthquake slip distributions, variations in rupture velocities, radiated energy and stress drop, and relationships to aftershock distributions and afterslip are discussed. Seismic sequences for very large events have some degree of regularity within subduction zone segments, but this can be complicated by supercycles of intermittent huge ruptures that traverse segment boundaries. Factors influencing variability of large megathrust ruptures, such as large-scale plate structure and kinematics, presence of sediments and fluids, lower-plate bathymetric roughness, and upper-plate structure, are discussed. The diversity of megathrust failure processes presents a suite of natural hazards, including earthquake shaking, submarine slumping, and tsunami generation. Improved monitoring of the offshore environment is needed to better quantify and mitigate the threats posed by megathrust earthquakes globally.

show abstract

A detailed source model for the M_w9.0 Tohoku‐Oki earthquake reconciling geodesy, seismology, and tsunami records

Cited by 72 publications

References 88 publications

Source process with heterogeneous rupture velocity for the 2011 Tohoku-Oki earthquake based on 1-Hz GPS data

Source process with heterogeneous rupture velocity for the 2011 Tohoku-Oki earthquake based on 1-Hz GPS data

Dynamics of a fault model with two mechanically different regions

Subduction zone megathrust earthquakes

Contact Info

Product

Resources

About