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The 17th July 2006 Pangandaran-Java earthquake with magnitude Mw7.7 generated tsunami 20.9 m. Large earthquake in the subduction zone has a potential recurrence near Sunda Strait. Aim of study is to assess potential tsunami in Anyer and Cilegon by the expected tsunami source near Sunda strait. The source are the 1903 Pelabuhan Ratu event for normal fault and the 2006 Pangandaran event for thrust fault. The scenario is based on Yanagisawa's model to create the inundation map and the evacuation route. The parameter of strike, dip, rake, and depth are respectively 297°,7°,102° and 20 km. The epicenter is 106.40°E, 7.98°S with the magnitude Mw8.7, fault size of 500 km x 225 km, and slip is 8.92 m. We merged GEBCO bathymetry with SRTM-DEM topography to get a precise result in smallest region. Travel time of thrust fault is faster than normal fault with interval of 62.2 minutes. The maximum tsunami height are 2.26 m for thrust fault in Jayakarta-Anyer beach, and 2.8 m for normal fault in Merak Port-Cilegon. The propagation in wider region of linear water is nearly same as opposite shape, but different in smallest region of non linear water near the coast. Jayakarta is one of the Anyer coastal area that is completely submerged by tsunami inundation range up to 250 m and tsunami height to 4 m. Almost Cilegon area has wider inundation distribution and amplified tsunami height inland because of its shallower bathymetry. Mitigation plan should be improved by installing more routes, signs maps, and other rescue facilities in Anyer and Cilegon. [ABSTRACT FROM AUTHOR]

Sunda strait lies in the transition zone of two different subduction system that is almost perpendicular to the subduction in southern Java and obhque subduction in western Sumatra. Tlie series of major disasters such as earthquakes and volcanic eruptions is a manifestation of its tectonic setting complexity. We used selected waveform data ffoin724 earthquakes that occurred around the Sunda strait and western part of Java from 2009 - 2015 recorded by 21 MCGA network stations to construct three dimensional image of seismic attenuation. Frequency independent attenuation operators (t*) was determmed using spectral fitting method for P and S wave arrivals, respectively. The inversion was performed using simul2000 algorithm to image the lateral and vertical variations of Qp and Qs value in the Sunda Strait and western part of Java. Some interesting features such as subducting slab, mantle wedge, magma chamber under volcanos and fault zones can be imaged well. [ABSTRACT FROM AUTHOR]