For large earthquakes occurred at and around plate boundaries, we examined relations between seismic moment M 0 , fault length L, fault width W and average fault slip D, and found the following scaling laws. For interplate strike-slip events, the well-known L-cubed dependence of seismic moment M 0 breaks when L exceeds 30 km, and D and M 0 increase with L as D = L==(L+) and M 0 = WL 2 =(L +), r...

The 1946 Aleutian earthquake was a typical tsunami earthquake which generated abnormally larger tsunami than expected from its seismic waves. Previously, Johnson and Satake (1997) estimated the fault model of this earthquake using the tsunami waveforms observed at tide gauges. However, they did not model the second pulse of the tsunami at Honolulu although that was much larger than the first pu...

On 1 April 2007 a great, tsunamigenic earthquake (moment magnitude 8.1) ruptured the Solomon Islands subduction zone at the triple junction where the Australia and Solomon Sea-Woodlark Basin plates simultaneously underthrust the Pacific plate with different slip directions. The associated abrupt change in slip direction during the great earthquake drove convergent anelastic deformation of the u...

The fault geometry, depth, and slip distribution of the Kurile earthquake of Oct. 4, 1994 are estimated using seismic waveforms, aftershock distribution, geodetic measurements, and tsunami waveforms. Previous large earthquakes in the Kurile arc had typical underthrusting focal mechanisms due to the local subduction. Seismic wave inversions of the 1994 event indicate a thrust type mechanism with...

When subduction initiates along a transform fault, it is often interpreted that the older and therefore denser oceanic lithosphere should evolve into downgoing plate. However, in western Pacific, several geological cases are probably characterized by young plates underthrusting plates. Using numerical simulations of fault under compression, we propose polarity depends mainly on age offset betwe...

The magnetotelluric method has improved significantly in recent years and is being used in hydrocarbon exploration in regions where seismic exploration is difficult. This includes areas where highvelocity carbonates and volcanic rocks are present in the near surface, overthrust belts, and in subsalt imaging. Magnetotelluric exploration was used in the Rocky Mountain Foothills in 2002 to determi...

The lateral (along trench axis) variation in the mode of large earthquake occurrence near the northern Japan Trench is explained by the variation in surface roughness of the subducting plate. The surface roughness of the ocean bottom near the trench is well correlated with the large-earthquake occurrence. The region where the ocean bottom is smooth is correlated with 'typical' large underthrust...