Tsunami Characteristics
The rupture velocity of earthquakes is another factor that determines the magnitude of a tsunami.  The term tsunami earthquakes was coined by Hiroo Kanamori in 1972 to describe when an earthquake having a slower rupture velocity (~1km/sec), compared to a more normal velocity (2.5-3.5 km/sec) of a typical earthquake, causes a tsunami greater in magnitude than expected. 

This paper investigates the effect of a horizontal movement of sediments due to an 1896 earthquake that may have created a tsunami earthquake.