earthquake

The definition of an earthquake is the release of sudden and extreme energy that is caused by shifting in the Earth's crust.

Facts About Earthquakes

• A seismometer is used to record and measure the strength of an earthquake.

• The Mercalli scale is used to measure the earthquake. Anything seven or above is considered extremely dangerous.

• Earthquakes usually occur along fault lines, or cracks that occur within the Earth’s crust.

• Japan, New Zealand, Alaska are all located on one side of a horseshoe-shaped fault line called the "Ring of Fire" that circles the Pacific Ocean and is responsible for frequent earthquakes and frequently erupting volcanos.

• The "Ring of Fire" zone was responsible for the devastating earthquakes in Indonesia in 2004, in New Zealand in early 2011 as well as a 9.0+ quake and a series of offshore earthquakes in Japan in early 2011 which also resulted in a tsunami.

• The San Andreas Fault is a fault line discovered in 1895 that stretches about one thousand and three hundred kilometers through California in the United States, and through Baja California in Mexico.

• The San Andreas fault has been the cause behind a number of significant earthquakes, such as the San Francisco Earthquake in 1906, and the Loma Prieta Earthquake in 1989.