Landslide tsunami hazard in the Indonesian Sunda Arc

Abstract

Abstract. The Indonesian archipelago is known for the occurrence of catastrophic earthquake-generated tsunamis along the Sunda Arc. The tsunami hazard associated with submarine landslides however has not been fully addressed. In this paper, we compile the known tsunamigenic events where landslide involvement is certain and summarize the properties of published landslides that were identified with geophysical methods. We depict novel mass movements, found in newly available bathymetry, and determine their key parameters. Using numerical modeling, we compute possible tsunami scenarios. Furthermore, we propose a way of identifying landslide tsunamis using an array of few buoys with bottom pressure units.

Discovery of possible mega-thrust earthquake along the Seram Trough from records of 1629 tsunami in eastern Indonesian region

“…For example, active strike-slip faults are inferred to the west of Banda Neira (Mccaffrey and Nabelek 1984) that, with a significant component of oblique slip, may produce a large tsunami if the rupture zone parameters are large enough. It is also possible that an earthquake-induced landslide generated the tsunami (Brune et al 2010). Nevertheless, the extent to which the earthquake was felt, and the prolonged seismicity following the event, indicates that the earthquake was larger than any event occurring over the past 100 years of instrumental records.…”

“…Little is known about the event (Okal and Reymond 2003), but the tsunami was small and caused no damage. In 1899, a M s = 7.8 earthquake struck the Seram region and generated a 10-m tsunami, that was perhaps landslide-assisted, killing around 3,500 persons (Brune et al 2010). With elastic strain energy accumulating across the Seram Trough at a rate of 50-80 mm/a (Bock et al 2003), it is likely that earthquake recurrence intervals are short (*100 years).…”

Simulation of space-borne tsunami detection using GNSS-Reflectometry applied to tsunamis in the Indian Ocean

“…Tropospheric effects are dominated by the water vapor content which is highly variable especially in tropical regions (Heise et al, 2006). The properties of the reflecting surface like roughness or to a lower extent temperature, salinity, polarity and permitivity also may contribute to the overall error (Cardellach, 2001). The reflected signal has to pass the troposphere and ionosphere again until it can be received by the GNSS-R satellite antenna.…”

“…This means that tsunamis should be detected on the open sea within only 15 min after their generation by an earthquake or another triggering event like, e.g. a submarine slide (Brune et al, 2010). In the case of GITEWS an epicenter will be localized by a network of seismometers (Hanka et al, 2008) and GPS deformation monitoring stations Falck et al, 2010) very quickly, but these do not provide any information if a tsunami has been generated or not.…”

Postface "The GITEWS Project – results, summary and outlook"

“…The distribution of submarine landslides and the associated tsunami hazard has been investigated by Brune et al (2010).…”