Linkages between turbidites in the southern Okinawa Trough and submarine earthquakes

Abstract

Turbidite layers in surficial (<0.4 m) sediments of the southern Okinawa Trough and its vicinity were dated by 210 Pb and further constrained by 137 Cs and inter‐site correlation of downcore profiles of particle size and porosity. Here we show striking temporal and spatial correspondence of such episodic deposits to large (M L > 6.8) submarine earthquakes recorded in the region since the 20th century. The repeating pattern of turbidite layers reported here on decadal to centennial time scales suggests what may be the long‐term rhythm of seismic activities at this tectonically active plate boundary.