Sharpen Your Mind: Earthquakes

Earthquakes are caused by movement of the earth's plates. Quakes are measured on the Richter scale, named after one of two scientists who created this measurement system.

Earthquakes are primarily caused by movements of the earth's plates. The planet Earth's surface is in slow, but continual motion. Beneath our visible land and oceans are 25 to 50 mile-thick masses, called plates.

When these plates collide or rub up on each other the result is an earthquake. Earthquakes are fairly common. On average, there are two magnitude 2.0 or greater quakes each day.

Earthquake intensity is measured on the Richter scale, which is an exponential scale. Each whole number increase on the Richter is a ten-fold increase in intensity, so a magnitude 6 earthquake is ten times stronger than a magnitude 5. Although the scale does not have an upper boundary, a magnitude 9 is the strongest measured thus far.

Interesting Trivia: Charles Richter and Beno Gutenberg, two geologists at Caltech in California, jointly developed the earthquake magnitude measurement system. However, it became known as the Richter scale almost immediately despite Richter's modesty. He always referred to it as the Magnitude Scale.

Source: The Intellectual Devotional, David S.Kidder & Noah D. Oppenheim and A Short History of Nearly Everything, Bill Bryson