Research projects

We conduct researches on subduction earthquakes using seismic techniques. Our main research areas are the subduction zones around Japan, but we also go to other subduction zones around the world for better understanding of the subduction processes.

Regional studies

Around Japan

Off Ibaraki; S limit of Tohoku EQ

  • Southern end of Tohoku-EQ; its largest aftershock
  • Subduction of a seamount of a size of Mt. Fuji
  • Repeating M7 earthquakes

39˚N; N limit of Tohoku EQ

  • Clear boundary of seismicity along 39˚N
  • Large contrast of seismic reflectivity of the plate interface
  • Reflectivity contrast may be explained by distribution of fluid

Nankai Trough; Off Kii Pen.

  • Clear boundary of historical Tonankai and Nankai EQs
  • Structural heterogeneity within the subducting PHS plate
  • Stepwise change in depth of seismicity at the fault boundary

Nankai Trough - Hyuga Nada

  • Clear boundary of historical Tonankai and Nankai EQs
  • Structural heterogeneity within the subducting PHS plate
  • Stepwise change in depth of seismicity at the fault boundary

Other subduction zones

Hikurangi, NZ

  • Shallow seismicity and plate interface
  • Striking contrast of plate-interface coupling strength
  • Frequent + repeating slow EQs

Data analysis methods

coming soon...