What is the Richter Scale?

 The most commonly known measurement is the Richter scale. It was created in 1935 by Charles F. Richter at the California Institute of Technology. The Richter scale measures the amplitude of seismic waves. Basically it measures an earthquake’s size.

The Richter scale uses a logarithmic scale, where each full step (for example going from a magnitude 1.0 to 2.0) is 10 times greater than the one before. A magnitude 2.2 tremor would be 10 times bigger than a 1.2 and a 3.2 is 100 times bigger. A minor 4.2 quake is 1000 times bigger. Continuing on, a magnitude 7.2 earthquake is one million times larger than the 1.2 tremor.

Some of the biggest advantages of the Richter scale was its simplicity and it corresponded with observable damage, which made it very useful for designing and building earthquake-resistant structures.

While the Richter scale is useful for measuring the size of an earthquake, there are some disadvantages. It is a local magnitude scale which means it isn’t very reliable for measurements taken from further than 370 miles away. The scale also has a limitation in its highest measurable magnitude, which means all large earthquakes tend to have magnitude 7.  However, it is still used for small and medium earthquakes. The Richter scale is still a useful scale, particularly in the local area of the earthquake, and it is sometimes referred to as local magnitude (ML) or Richter magnitude

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