The 2011 Tohoku earthquake (Mw 9.0) produced a very large slip on the shallow part of a megathrust fault that resulted in destructive tsunamis. Although multiple causes of such large slip at shallow depths are to be expected, the frictional property of sediments around the fault, particularly at coseismic slip velocities, may significantly contribute to large slip along such faults. We have thu...

Subduction earthquakes on plate-boundary megathrusts accommodate most of the global seismic moment release, frequently resulting in devastating damage by ground shaking and tsunamis. As many earthquakes occur in deep-sea regions, the dynamics of earthquake faulting in subduction zones is poorly understood. However, the Integrated Ocean Drilling Program (IODP) Nankai Trough Seismogenic Zone Expe...

[1] We report on laboratory experiments which investigate interactions between aseismic slip, stress changes, and seismicity on a critically stressed fault during the nucleation of stick-slip instability. We monitor quasi-static and dynamic changes in local shear stress and fault slip with arrays of gages deployed along a simulated strike-slip fault (2m long and 0.4m deep) in a saw cut sample o...

Field investigations and analyses of satellite images and aerial photographs reveal that the 2016 Mw 7.1 (Mj 7.3) Kumamoto earthquake produced a ∼40-km surface rupture zone striking NE-SW on central Kyushu Island, Japan. Coseismic surface ruptures were characterized by shear faults, extensional cracks, and mole tracks, which mostly occurred along the pre-existing NE-SW-striking Hinagu-Futagawa ...

A better understanding of fluid-related processes such as poroelastic rebound of the upper crust and weakening of the lower crust beneath the volcanic arc helps better understand and correctly interpret the heterogeneity of postseismic deformation following great subduction zone earthquakes. The postseismic deformation following the 2011 Mw9.0 Tohoku earthquake, recorded with unprecedented high...

[1] Subducted seamounts have been linked to interplate earthquakes, but their specific effects on earthquake mechanism remain controversial. A key question is under what conditions a subducted seamount will generate or stop megathrust earthquakes. Here we show results from numerical experiments in the framework of rateand state-dependent friction law in which a seamount is characterized as a pa...

Mega quakes pose major threats to modern society, generating casualties and fatalities, disrupting socioeconomic activities, and causing enormous economic loss across the world. Recent major disasters, such as the 2004 Indian Ocean tsunami, the 2011 Tohoku Japan earthquake and tsunami, and the 2015 Gorkha Nepal earthquake, are vivid reminders that complex risk cascades drive most earthquake cri...

The December 26, 2004 Sumatra–Andaman Island earthquake, which ruptured the Sunda Trench subduction zone, is one of the three largest earthquakes to occur since global monitoring began in the 1890s. Its seismic moment was M0 = 1.00 · 10–1.15 · 10 Nm, corresponding to a moment-magnitude of Mw = 9.3. The rupture propagated from south to north, with the southerly part of fault rupturing at a speed...

The damaged rock around mature faults forms a zone of low seismic wave 24 velocities, which can perturb important earthquake rupture properties. In particular, waves 25 reflected within the fault zone structure can induce short-duration slip pulses, an apparently 26 predominant earthquake rupture mode. Another known mechanism to generate slip pulses is 27 strong velocity-weakening friction. Her...

The Longmen Shan is the steepest topographic front at the India-Asia collision zone and the site of the Mw 7.9 Wenchuan earthquake. Here to explain the interseismic GPS velocities across the greater Longmen Shan region, we develop a boundary element model including earthquake cycle effects, topography, the westward dipping Beichuan Fault and a ∼20 km deep, shallowly dipping, detachment, inferre...