Japan has many earthquakes because it sits right on top of several colliding tectonic plates in a very active seismic zone called the Pacific Ring of Fire.
Plate boundaries under Japan
Japan lies where four major plates meet: the Pacific, Philippine Sea, Eurasian, and North American plates. These plates constantly push, scrape, and dive under one another (a process called subduction), which builds up stress in the crust and then releases it as earthquakes.
The Pacific Ring of Fire
Japan is located along the Pacific Ring of Fire, a 40,000‑kilometer belt around the Pacific Ocean where most of the world’s earthquakes and many volcanoes occur. This region produces over 80% of the world’s major earthquakes and tsunamis, so countries along it, including Japan, naturally experience frequent seismic activity.
Trenches and subduction zones
Off Japan’s coast are deep ocean trenches, like the Japan Trench, where the dense Pacific Plate sinks beneath lighter plates beneath the Japanese islands. These subduction zones are capable of generating very large earthquakes, such as the 2011 Tohoku quake, because huge amounts of energy can accumulate before being suddenly released.
How often quakes happen
Because of this unique tectonic setting, Japan experiences thousands of earthquakes every year, though most are too small to cause damage. The same tectonic forces that create Japan’s mountains and volcanoes are also responsible for making earthquakes a normal part of life there.
