Posts Tagged ‘earthquakes’

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What am I celebrating ?

April 26, 2016

richter Moment Magnitude Chart

 

richterToday is Richter Scale Day when we commemorate the birth of Charles Richter.  In 1935, the seismologists Charles Francis Richter and Beno Gutenberg, of the California Institute of Technology, developed the (future) Richter magnitude scale, specifically for measuring earthquakes in a given area of study in California, as recorded and measured with the Wood-Anderson torsion seismograph. Richter derived his earthquake-magnitude scale from the apparent magnitude scale used to measure the brightness of stars.

Richter’s scale (which has been replaced by the Moment Magnitude Scale) measures the magnitude of an earthquake.  The magnitude value is proportional to the logarithm of the amplitude of the strongest wave during an earthquake.

This very cool video explains magnitude . . .

Adapted from Wikipedia

 

 

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What has no upper limit?

April 26, 2013

Get ready to rumble – there’s a whole lot of shaking going on because today is Richter Scale Day.  April 26 is the birthday of Charles Richter (born in 1900 in Overpeck, Ohio) who developed the eponymous scale for comparing earthquakes.  Richter repeated emphasized that there is no upper limit to the scale, however each level of the scale represents a ten-fold increase in magnitude from the previous level.  The most powerful earthquake recorded was the 1960 Chilean earthquake that measured 9.5 on the scale.

Magnitude differs from intensity, as explained on the USGS earthquake site:

Magnitude and Intensity measure different characteristics of earthquakes. Magnitude measures the energy released at the source of the earthquake. Magnitude is determined from measurements on seismographs. Intensity measures the strength of shaking produced by the earthquake at a certain location. Intensity is determined from effects on people, human structures, and the natural environment.

For a comparison of magnitude versus intensity, look here.

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earthquakes

Read an interview with Charles Richter here.

Read more about earthquakes here.