Whenever there is an earthquake, we read or hear about a certain magnitude of it. But how does it work? The Richter scale, named after the American seismologist Charles Francis Richter, is a scale that assigns a number to quantify the energy released by an earthquake. It was created in 1935 by Richter and Beno Gutenberg (both from the California Institute of Technology), in order to measure the strength of earthquakes according to their magnitude , that is, according to the amount of energy released during the earthquake in question.
The formula to calculate the magnitude of an earthquake is as follows:
According to the scale, the assigned values increase logarithmically and not linearly , similar to the stellar magnitude scale used in astronomy to measure the brightness of stars. Thus, an earthquake of intensity 4 is not twice that of an intensity 2, but 100 times higher and so on.
The Richter scale goes up to 12 degrees, where an earthquake of these characteristics would have the same power as 1 billion tons of trinitrotoluene with enough force to fracture the Earth at the core.
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Richter scale classification and its impact on the surface:
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Less than 3.9: Generally not perceived
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4 to 4.9: Often noticeable, but with unlikely damage
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From 5 to 5.9: It is perceived, but only causes minor damage; in old buildings it can be serious damage
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6.0 to 6.9: Can cause severe damage in populated areas within 100 miles
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From 7.0 to 7.9: Major earthquake. It can cause serious damage in many areas and there is usually about 18 per year.
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From 8.0 to 8.9: This is a large earthquake that can cause serious damage in areas of several hundred kilometers. They are produced 1 to 3 per year.
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From 9 to 9.9: They are devastating earthquakes in several thousand kilometers. They occur 1 or 2 every 20 years.
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10 or more: None have been registered yet. Its consequences would be epic.
Taking into account that earthquakes began to be measured in the 20th century, the largest earthquake in history was the one registered in Valdivia, Chile, in 1960 . The earthquake was of magnitude 9.5. There were 2,000,000 victims and Valdivia sank 4 meters below sea level, also producing the eruption of the Puyehue volcano.
Charles Francis Richter
Charles F. Richter (1900-1985) was one of the developers of the Richter scale that is used to measure the magnitude of earthquakes. Richter, who devoted his entire life to work, was a pioneer in seismological research at a time when data on the size and location of earthquakes were rather scarce. He is the author of two textbooks that are still used as a reference and are considered by many scientists as his greatest contribution , even exceeding the Richter scale itself.
