Earthquakes, Plate Tectonics, Earth Structure

Learn more: Earthquakes by State/Territory or Earthquakes by Country/Region.
An earthquake is caused by a sudden slip on a fa
Earthquakes induced by human activity have been documented at many locations in the United States and in many other countries around the world.
"Foreshock" and "aftershock" are relative terms. Foreshocks are earthquakes that precede larger earthquakes in the same location.
The moon, sun, and other planets have an influence on the earth in the form of perturbations (small changes) to the gravitational field.
Surface rupture occurs when movement on a fault deep within the earth breaks through to the surface. NOT ALL earthquakes result in surface rupture.
Earthquakes occur in the crust or upper mantle, which ranges from the earth's surface to about 800 kilometers deep
Five billion years ago the Earth was formed by a massive conglomeration of space materials. The heat energy released by this event melted the entire planet, and it is still cooling off today.
The Geysers Geothermal Field is located in a tectonically active region of Northern California.
Earthquakes do occur occasionally in Antarctica, but not very often. There have been some big earthquakes--including one magnitude 8--in the Balleny Islands.