There are about 500,000 detectable earthquakes in the world each year. 100,000 of those can be felt, and 100 of them cause damage.
The average rate of motion across the San Andreas Fault Zone during the past 3 million years is 56 mm/year (2 in/year). This is about the same rate at which your fingernails grow. Assuming this rate continues, scientists project that Los Angeles and San Francisco will be adjacent to one another in approximately 15 million years.
The deepest earthquakes typically occur at plate boundaries where the Earth's crust is being subducted into the Earth's mantle. These occur as deep as 750 km (400 miles) below the surface.
An estimated 500,000 detectable earthquakes occur in the world each year. About 100,000 of those can be felt and 100 of them cause damage.
Like all mountain ranges, the Wasatch Range, which runs north to south through Utah, was created by a series of earthquakes. The 240-mile Wasatch Fault is made up of several segments, each capable of producing a magnitude 7.5 earthquake. During the past 6,000 years, there has been a magnitude 6.5 or higher earthquake about once every 350 years, and it has been 150 years since the last powerful earthquake.
Florida and North Dakota have the fewest earthquakes in the United States.
Alaska is the most earthquake-prone state and one of the most seismically active regions in the world. Alaska experiences a magnitude 7 earthquake almost every year, and a magnitude 8 or greater one on average every 14 years.
When the Chilean earthquake occurred in 1960, the largest earthquake recorded since 1900 at 9.5 magnitudes, seismographs recorded seismic waves that traveled all around the Earth for days after the event. This phenomenon is called the free oscillation of the Earth.