Submarine active fault map of the eastern part of Sea of Japan

Abstract

The eastern part of Sea of Japan is seismically active region. Therefore, it is essential to examine submarine active faults in order to make an accurate estimate of future large earthquake and tsunami. We executed tectonic geomorphological research on the submarine topography in this region, and investigated feature of active structures in this region based on 3D anaglyph images, which have 250 m resolution. There are long active faults trending in NNW-SSE direction in the northern part of the region. In the southern part, high-density active faults in NNE-SSW direction are dominant. The source fault of the large earthquake in 1983 is exactly mapped. However, the active faults originated the 1993 earthquake has gone missing.