Earthquake-induced surface-sediment remobilization and paleoseismology using its related event deposits

Abstract

Short historical and shorter instrumental records limit our perspective of earthquake maximum magnitude and recurrence, and thus are insufficient to fully understand multiscale seismic behavior and its consequences. Examining long-term prehistoric events in the geological record is important for characterizing the recurrence patterns of large and great earthquakes and for reducing uncertainties in seismic hazard assessment. Earthquake-induced event deposits in marine sediments such as deep-sea turbidites, which have been formed by every large earthquake in the past, are one of the geological records used for understanding the long-term history of past large and great earthquakes. Surface-sediment remobilization is a suitable mechanism for the initiation of earthquake-induced turbidity currents and for deep-sea turbidite paleoseismology, although submarine landslides have been considered to be major contributors for the initiation of earthquake-induced turbidity currents. Here, I would like to review recent studies on the surface-sediment resuspension and remobilization by large and great earthquakes and paleoseismology using its related event deposits, and to discuss the future direction of deep-sea turbidite paleoseismology.