One of the initial characterizations of tsunami earthquakes came from seismologist Hiroo Kanamori in the early 1970s , and additional clarity materialized following the 1992 Nicaragua earthquake and tsunami , which was evaluated to have a surface wave magnitude of 7.0 when analyzing short period seismic signals . When longer period signals of around 250 seconds were investigated , the shock was reevaluated to have a moment magnitude of 7.6 , with a hypothesis that the slow nature of the slip of the event may have concealed its substantial extent . Sediment was thought to have contributed to a slower rupture , due to a lubrication effect at the plate interface , with the result being an earthquake signature that had abundant long period seismic signals , which could be an important factor in the tsunami-generation process
1992 Nicaragua earthquake and tsunami
1992 Nicaragua earthquake
2006 Pangandaran earthquake and tsunami