earthquake magnitude

geology

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July 16, 2026

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Earthquake magnitude measures the size of seismic waves generated by an earthquake. Initially, Charles F. Richter developed a scale using the logarithm of the largest seismic wave's amplitude. This Richter scale was effective for moderate earthquakes but had limitations for larger ones.12

Currently, the moment magnitude scale is preferred. It more accurately measures an earthquake's total energy release by considering the fault's geometry and displacement. Magnitude scales have no theoretical upper limit, but practical measurements rarely exceed 9.0. The intensity of shaking, however, is described by qualitative scales like the Mercalli scale, which differs from magnitude.345

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earthquake
Earthquake magnitude
Earthquake magnitude is a measure of the “size,” or amplitude, of the seismic waves generated by an earthquake source and recorded by seismographs. (The types and nature of these waves are described in the section Seismic waves.) Because the size of earthquakes varies…
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Earthquake magnitude is a measure of the “size,” or amplitude, of the seismic waves generated by an earthquake source and recorded by seismographs. (The types and nature of these waves are described in the section Seismic waves.) Because the size of earthquakes varies…
Read More