It was early morning, January 17, 1994. John and his wife were asleep in their house Northridge, California. Suddenly, the loudest thunder they’d ever seemed to explode right out of the ceiling, floor, and the walls. They were thrown onto floor. The dresser, on the other side of bed, crashed onto the bed, which was shaking bouncing violently. Paintings and a mirror flew off bedroom walls. Their bedroom windows broke and the cracked as the foundation of the house moved.

Northridge quake was “only” 6.8 on the Richter (10 is maximum). There have been many earthquakes than the Northridge one. The strongest quake ever , 9.5, occurred in Chile in 1960.

Each whole on the Richter scale equals ten times the of the previous number. That is, a 3.0 is ten times as powerful as a 2.0 . Quakes are measured on instruments called seismographs.

Earthquakes occur where tectonic plates meet. About 30 of plates cover the Earth. They are several miles and huge in area—most of the Pacific Ocean on just one plate.

Earthquakes occur when one strikes another or slides beneath another. Either action a huge amount of energy that travels upwards the surface of the land or upwards to surface of the ocean floor. A powerful earthquake the ocean floor produces a tsunami.

It is -known that various kinds of animals act oddly just an earthquake occurs. Researchers hope to discover how animals can actually detect an earthquake. They’ll use knowledge to try to create an early warning to save human lives. We’ll never be able take the power out of an earthquake, but someday we can take out the surprise.