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Moment Magnitude (Mw)

The modern earthquake magnitude scale, based on the seismic moment released.

Formula

M_w = \tfrac{2}{3}\log_{10}(M_0) - 10.7

Variables

M_wMoment magnitude

M₀Seismic moment (dyn·cm)

Example

A tenfold larger M₀ raises Mw by about 0.67

Did You Know?

Moment magnitude replaced Richter for large quakes because Richter "saturates" past ~M7.

earthquake seismic disaster geology

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