This document analyzes three major earthquakes - the 2009 Samoa Earthquake, the 2010 Chile Earthquake, and the 2011 Tohoku-Oki Earthquake - through tsunami simulation modeling to better understand the focal characteristics and geometry of the fault planes. The modeling fits well with observational tsunami data and supports the seismic source models provided by USGS. It also confirms that altimetry satellites can detect shelf resonance tsunami signals over 1.5 meters even 3 hours after earthquakes. For the 2011 Tohoku-Oki Earthquake, modeling shows maximum slip closer to the trench. Tsunami simulation also helps discriminate the actual fault plane orientation for the 2009 Samoa Earthquake.

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Abstract
Differentiating from seismometric observations, tsunami waves can provide us
another clue in the seismic source. In this study, we study through three big earthquakes
by means of tsunami simulation to obtain more comprehension of their focal
characteristics. They are the events: the 2009 Samoa Earthquake, the 2010 Chile
Earthquake and the 2011 Tohoku-Oki Earthquake. By testing varied rupture models of
fault planes in simulation, we can verify and infer the orientation and geometry of the
real fault planes. In this study, we use the tsunami modeling package – COMCOT; and
the observed record are from the ocean bottom pressure recorders and the altimetry
satellites. Based on the resolved slip distribution from USGS, the simulated results fit
well with the observation, which supports the seismic source for the one has two
asperities and mostly located in the coastal region. In addition, we also confirm that the
altimetry satellite can successfully detect the shelf resonance signal of the tsunami,
which can be up to 1.5 meters even at the time for 3 hours after the earthquake time. In
the case of the 2011 Tohoku-Oki Earthquake, the simulated tsunami waveforms show
that the maximum slip located much closer to the trench. Except for using different
static slip distributions, we also adopt the rupture model involving with time evolution
to discuss the effect on the initial sea surface height of tsunami from the progress of
rupture. Also, tsunami waves can help to distinguish the actual fault plane. In the 2009
Samoa Earthquake, firstly, by the means of tsunami simulation, it shows that not only
the normal fault, but also the thrust should be taken as to provoke the tsunami waves.
Furthermore, we can discriminate the real orientation of the normal faulting as the one
dipping to the north-east. Besides, we calculate the coseismic dislocation at the near-by
GPS stations as well, and show that the modeling of coseismic dislocation cannot help

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to tell apart the real fault plane. This experience is taken to examine the former
researches who explained the stress transfer in the 2009 Samoa Earthquake by means of
GPS dislocation analysis.
Keywords: Tsunami, seismic source, the 2010 Chile Earthquake, the 2011
Tohoku-Oki Earthquake, the 2009 Samoa-Tonga Earthquake, COMCOT, DART,
Altimetry Satellite, GPS, coseismic displacement