The Philippine Sea plate is tectonically unusual in that almost all the boundaries are convergent. The Pacific plate is subducting beneath the Philippine Sea plate to the east while the west/northwestern part of the Philippine Sea plate is subducting beneath the continental Eurasian plate. There are shorter boundaries of the Philippine Sea plate with the Okhtosk plate to the north, and the Australian plate to the south. The relative plate motions and boundaries are all clearly depicted in Figure 1. Transform faults are also found near Taiwan and the Philippine trench. The relative plate motion of the Philippine Sea plate is ~80mm/yr relative to the Eurasian plate (Smoczyk et al., 2013) and is actively in motion today increasing the likelihood of earthquakes and tsunamis to occur in the near future. The plate thickness varies throughout the plate where Yoshioka and Ito (2001) calculated values between 29-41km around the Nankai trough. They suggest variations in the thickness are dependent on the age of the sea floor and the process of formation.