A. Simanjuntak¹ , I. Nurdin² , S. Usman³ , M. Umar²

¹National Seismological Center, Meterological and Geophysical Agency
²Tsunami Disaster and Mitigation Research Center
³University of Syiah Kuala

Abstract:

We calculated some devastating earthquake energies for events that occurred in subduction zone and followed by aftershocks. We compared the amount of energy released between mainshock and aftershock with the empirical formula from the Gutenberg- Richter relation. Historical data with three months aftershocks after five major earthquakes (Bengkulu, Pangandaran, Simeulue, West Sumatra, and Tasikmalaya) were obtained from the International Seismological Center. From analysis and energy calculations of earthquake aftershocks from major earthquakes with a magnitude larger than 5.0, energy aftershocks ranging from 0.1% to 33%, with a random pattern. By comparing the energy aftershocks of earthquakes, the results are generally 10%, it is estimated that the earthquake with strike-slip mechanism having earthquake aftershocks with total energy less than 10%. The earthquakes which have aftershocks and thrust mechanism make a total energy more than 10%. By obtaining these comparisons, this research is based on scientific studies can be used as a reference to providing information on the possible impact of an occurrence of the earthquake and its aftershocks.