Large earthquakes repeatedly occur along subduction zones, and some of them become extraordinary events that generate large tsunami waves. The 2011 Tohoku and 2004 Sumatra–Andaman earthquakes are typical examples of such exceptional events. These earthquakes are thought to recur at intervals of several hundred years or longer, and only geological records spanning hundreds to thousands of years can reveal their recurrence history.
The Subduction Zone Paleoearthquake Research Group combines methods from geomorphology, sedimentology, paleontology, and geochemistry to investigate the recurrence intervals and magnitudes of past great subduction-zone earthquakes. We also aim to reconstruct the rupture areas of these earthquakes by integrating geophysical analyses, such as numerical simulations of tsunami inundation. Under AIST’s 6th Medium- to Long-Term Plan, our research focuses on the Japan Trench, the Sagami Trough, and the Nankai Trough. In addition, we are making previously collected data publicly available through the Tsunami Inundation History Maps.