The greatest flexural bending of the oceanic lithosphere and major earthquakes occur at subduction zones. When the bending stresses exceed the rock yield strength, pervasive normal faulting and extensional earthquakes would be generated within subducting plates. Normal faulting provides conduits for fluids to reach the upper mantle and facilitates serpentinization. Extensional earthquakes could also trigger tsunamis. Thus, better understanding flexural bending, stress distribution, and brittle failure of the subducting plate is essential to study the mechanism of earthquake and Earth's water cycle. Based on summary of geophysical observations and geodynamic simulations of the most representative Japan, Izu-Bonin, Mariana and Yap subduction zone and Tonga-Kermadec subduction zone in the western Pacific Ocean, this paper presents overview of characteristics of plate bending, bending-related normal faulting and corresponding brittle yield zone. The distribution characteristics of bending-related normal faults in different subduction zones were analyzed, and the correlations between plate deformation and earthquakes were discussed. It reveals the potential plate hydration characteristics of bending plates with normal faults. This study provides a basis for the future research on the plate deformation mechanism of subduction zones.

plate bending  /  bending-related normal fault  /  brittle yield zone  /  plate hydration  /  western Pacific Ocean