Submarine active faults and large earthquakes along plate boundaries

-An issue raised by tectonic geomorphology-

Abstract

Active faults along the plate boundaries around Japan islands are results of repeated large earthquakes. We discuss on relation between large earthquakes and their source faults based on a detailed active fault map. Judging from location and continuation of active fault along Japan trench, we presume that an extensive thrust which extends from off-Sanriku to off-Ibaraki for about 500km, is directly related to the source fault of the 2011 Tohoku Earthquake. Expected mega earthquake along Nankai trough will be caused as one of the characteristic earthquakes related with submarine active faults that generated historical earthquakes.