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Available at: http://www.tectonics.caltech.edu/slip_history/2005_sumatra/sumatra.html, Ji, C. (2007). In total, 600 synthetic earthquake slip models are generated to obtain multiple realizations of maximum tsunami wave heights at various locations in Padang areas. In recent years, the Indonesian government, along with other groups like the Earth Observatory of Singapore and the U.S. Pacific Tsunami Warning Center, has been introducing technologies to improve hazard forecasting, warning and mitigation. “If we had an earthquake or volcano, and lots of citizens accessed our websites for information, too often the sites crashed,” he says. (F) Mw 9.0 scenario considering uncertainty. As shown in Figure 3A, three rows having zero slips are removed to produce a trimmed slip distribution. Figure 5 presents a computational flowchart of the stochastic tsunami simulation. The results of estimated source parameters for the nineteen source models are shown in Table 1 and Figure 4. doi:10.1029/96GL00736, United States Geological Survey (USGS). (A) Tsunami source zone. The buoys’ placement results in little delay between the detection of an earthquake and the potential generation of a tsunami wave. 58, 40. doi:10.1142/S0578563416500108. For stochastic source modeling and Monte Carlo simulation, the Mentawai source zone is discretized into 10 km by 10 km sub-faults. Res. The earthquake source model considered by Muhari et al. (2016) for generating stochastic source models for the future tsunamigenic earthquakes in the Mentawai segment of the Sunda subduction zone can be justified. (2016). Stress Changes on the Sunda Megathrust Preceding the 8.4 2007 Earthquake Kelly Grijalva, Roland Bürgmann, and Edwin (Trey) Apel Introduction The 8.4 September 12, 2007 Sumatra earthquake's occurrence, close in time and space to the 2004 Sumatra-Andaman and 2005 Nias megathrust events, suggests that it could be a triggered earthquake. In total, 600 synthetic earthquake slip models were generated to obtain multiple realizations of maximum tsunami wave heights at various locations in Padang areas. Res. 111, B02407. Once a realistic stochastic source model is generated, the initial water surface elevation is calculated using Okada (1985) and Tanioka and Satake (1996) formulae which consider the deformation due to both vertical and horizontal displacements of seafloor. Res. Additionally, within the area of the Mentawai segment, Padang is one of the most anticipated areas to be affected by the tsunami compared to the other areas in the western coast of Sumatra. (B) Nested grid system for tsunami simulation in Padang. In total, 600 source models are generated to assess the uncertainty of tsunami wave characteristics and maximum tsunami wave height profiles along coastal line of Padang. (A) Mw 8.5 scenario without considering uncertainty. The top-edge of the fault plane is located at a depth of 3 km. “Now, volcanic eruptions are among the most predictable of geological disruptions,” Devy says. In general, the large variation of wave amplitudes from the 10th and 90th percentile curves suggests that the earthquake slip model is an important source of uncertainty for the tsunami prediction. Since 2004, much of the Sunda megathrust between the northern Andaman Islands and Enggano Island, a distance of more than 2,000 km, has ruptured in a series of large subduction zone earthquakes - most rupturing the plate boundary south of Banda Aceh. On April 1, 2007, a M8.1 interplate megathrust earthquake occurred at the western end of the trench, generating a … where P(k) is the power spectrum of von Kármán model and k is the wavenumber defined as, k=(Az 2kz 2+Ax 2kx 2)0.5 (Goda et al., 2016). The first step is to simply trim the slip distribution when rows/columns having zero slip exist along the edges of the slip distribution. J. Earthq. (A–D) Stochastic source models for the future tsunamigenic earthquake scenario by considering the uncertainty of the scaling relationships. Partial rupture of a locked patch of the Sumatra megathrust during the 2007 earthquake sequence. J. Geophys. U.S.A. 103, 19673–19677. Indonesia is a country with 55,000 kilometers of coastline and more than 266 million inhabitants living on 6,000 islands, many of which are among the most remote in the world, where cellphone and internet coverage is rare. The tsunami simulation results for the other scenarios are then discussed to evaluate the tsunami hazard potential in Padang areas. Seismology: earthquake risk on the Sunda trench. (A) Mw 8.5 scenario without considering uncertainty. The term megathrustdoes not have a widely accepted rigorous definition, but is used to refer to an extremely large thrust fault, typically formed at the plate interface along a subduction zone such as the Sunda megathrust. Figure 13. “We are trying to develop and integrate local wisdom with technology, so that communities can build the capacity to cope with the disaster themselves,” he says. Get quickly to higher ground — walk at least 3 kilometers away from the beach.”. The asperity areas of the 1797 event are closer to Padang in comparison with those of the 1833 event (Philibosian et al., 2014). In addition, effects of the 1797 event in Padang in terms of ground shaking and flow depth were greater than the 1833 event. The tsunami hazard evaluations using multiple scenarios show that Padang may face a significant risk due to the future tsunamigenic event from the Mentawai segment. Solid Earth 119, 7258–7287. doi:10.1785/0120050609, Borrero, J. C., Sieh, K., Chlieh, M., and Synolakis, C. E. (2006). The past seismicity in the Mentawai segment indicates that there were two major tsunamigenic events occurred in 1797 and 1833 (Mw ~8.8) that affected the coastal areas of Padang and Bengkulu. Bull. In addition, the maximum tsunami wave height profiles from the 200 stochastic models excluding the uncertainty and including the uncertainty are presented in Figures 10C,D, respectively. The fault rupture is assumed to occur instantaneously, while the duration of the simulation is set to 2 h and the time step for the simulation is 0.5 s, which satisfies the C.F.L. Comparison to the future tsunamigenic earthquakes by Goda et al odds with efforts. 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