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2008 GL PP NANANG T. PUSPITO 1.pdf
PUBLIC Vika Anastasya Kovariansi

The Indonesian Tsunami Early Warning System (Indonesian TEWS) consists of four main components, i.e. (a) earthquake monitoring system, (b) oceanographic monitoring system, (c) database of tsunami simulation, and (d) information dissemination system. The system is designed to issue a tsunami warning within 5 minutes after the earthquake occurrence. Decision of a tsunami warning issuance is based on the examination of the determined earthquake parameters, i.e. epicenter, focal depth, and magnitude. Therefore, it is very important to explore the characteristics of tsunamigenic earthquakes in the Indonesian region. Tsunamigenic earthquakes in the Indonesian region occurred along subduction zones of Sunda-Banda-Caroline-Philippine, Molucca Sea collision zone, Makassar Strait zone, and the Sunda back-arc thrusting zone. In term of their earthquake magnitude, most of tsunamis were generated by earthquakes that have moderate to great magnitude. The earthquake magnitude Ms varies from 5.8 to 9.0 and earthquake magnitude Mw varies from 5.8 to 9.3. About 94% of tsunamigenic earthquakes have earthquake magnitude Mw > 6.5, 79% have Mw > 7.0; 80% have Ms > 6.5, and 55% have Ms > 7.0. About 86% of tsunamigenic earthquakes are classified as shallow earthquakes that have focal depth < 60 km and about 75% of tsunamigenic earthquakes have focal mechanism of thrust fault type.