Magnitude determination using duration of high frequency energy radiation and displacement amplitude: application to tsunami earthquakes

Recently, we developed a new method to determine earthquake magnitudes using durations of high frequency energy radiation and the maximum displacement amplitudes, which can be measured from processing of first arriving P -waves. In the present study, we applied this method to the 1992 Nicaragua, 1994, Java, 1996 Peru, and 2006 Java earthquakes which have been suggested to be tsunami earthquakes. Our magnitude estimates for these earthquakes are consistent with the moment magnitudes in the Global CMT catalog, which demonstrates that our method is applicable to tsunami earthquakes. The analyzed tsunami earthquakes are characterized in our method as those with longer source durations and smaller displacement amplitudes.