As the world's tectonic plates crash, grind and dive into one another, they release their pent-up energy in giant earthquakes that can rock the ground, trigger volcanic eruptions, move mountains and unleash tsunamis.
And since scientists figured out how to measure earthquake magnitude in the early 1900s, some truly massive quakes have shaken our planet. These are the monstrous "megathrust" earthquakes, the most powerful quakes in the world. A huge fraction of these earthquakes occurred in a handful of subduction zones along the seismically restless "Ring of Fire" in the Pacific, where tectonic plates dive beneath one another.
