Spectral Characteristics of Tsunamis and Seiches Caused by Tectonism and Volcanism in Rabaul, Papua New Guinea

Tsunamis caused by earthquakes, volcanoes, or submarine landslides in the ocean surrounding Indonesia and Papua New Guinea can have an impact locally as well as along the northern coast of Australia. Records of tsunamis and seiches caused by tectonic earthquakes and volcanic eruptions have been maintained in Rabaul. The effects of different sources of tsunamis have been compared using spectral analysis of the digitized wave forms. Dominant periods of about 20-30 minutes are characteristics of the seiches in Rabaul harbour, a period that is also characteristic of tsunamis.