There are approximately 2,000 active faults throughout the land mass of Japan, and as a result, Japan has experienced many seismic hazards throughout its history.

Earthquakes can be divided into plate boundary earthquakes and intra-plate earthquakes. Plate boundary earthquakes occur when the oceanic plate subducts beneath the continental plate, causing the continental plate, which is being dragged the oceanic plate, to rebound uncontrollably, causing faults on the plate boundary to rupture, often accompanied major submarine deformation and tsunamis.

Intra-plate earthquakes, on the other hand, occur when faults within a plate are pushed together tremendous forces and the magma moves, causing shaking and rocking.

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