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Earth System Sciences
Geology
1935
Beginner

Richter Magnitude Formula

ML=log⁡10A−log⁡10A0M_L = \log_{10} A - \log_{10} A_0

Earthquake magnitude is logarithmic—each unit is ~10× amplitude increase.

By Charles Richter

Earth System Sciences
Richter Magnitude Formula
1935 · Charles Richter
Why it matters: Standardized earthquake measurement worldwide.

Discoverers: Charles Richter (1935)

What does it mean?

Earthquake magnitude is logarithmic—each unit is ~10× amplitude increase.

Why should I care?

Standardized earthquake measurement worldwide.

Variables & Units

SymbolNameUnitMeaning
MLM_LMagnitude—Local magnitude
AAAmplitude—Seismic wave amplitude
A0A₀Reference—Standard amplitude at distance

Worked Example

M7 releases ~32× more energy than M6.

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Sources & further reading

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Equation Universe

Richter Magnitude Formula

ML=log⁡10A−log⁡10A0M_L = \log_{10} A - \log_{10} A_0

Real-world impact

Seismology

Standardized earthquake measurement worldwide.

Photo: Unsplash — technology

Earthquake magnitude is logarithmic—each unit is ~10× amplitude increase.

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