Local tsunamis, submarine landslides and Pacific islands.
Susanne Pohler
Time: 1-2 pm
Venue: Marine Studies Lecture Theatre, Marine Campus
Several modest earthquakes occurred in the 1990s that generated surprisingly large tsunamis without any significant transoceanic tsunami. The term ‘local tsunami’ was coined for these phenomena. A number of studies concluded that submarine landslides were to blame for these events. In the Pacific, local tsunamis (known as Yoda or silent tsunamis in Japan) reached 26 m above sea level in Flores, Indonesia in 1992 and 15 m above sea level in Sissano, Papua New Guinea in 1998. The high waves coupled with the short lag time between the event and the response make these tsunamis particularly treacherous.
Pacific island nations are highly vulnerable to landslide-generated local tsunamis because of their steep slopes and high earthquake frequency. This presentation will review the records of submarine landslide-generated tsunamis in the University of the South Pacific member states and examine the various mechanisms that have triggered slope instability. The locations of prehistoric submarine landslides will be investigated and evaluated.
