The Richter magnitude of an earthquake is determined from the logarithm of the amplitude of waves recorded by seismographs. Adjustments are included to compensate for the variation in the distance …

Nov 26, 2018 · Graph showing the average annual occurrence and equivalent energy release for earthquakes of different magnitudes. Plot is from the EarthScope Consortium …

Dec 20, 2025 · Interactive map displaying earthquakes detected by the PNSN in the last two weeks.

Jul 19, 2023 · Learn about the Richter scale and how it measures the magnitude of an earthquake. Compare it to the moment magnitude scale.

Depending on the size, nature, and location of an earthquake, seismologists may use several different methods and even different magnitude scales to estimate magnitude.

1 day ago · Track earthquakes today with real-time updates, maps, and seismic data. Stay informed with QuakePulse's live earthquake tracker.

Each increase of one unit on the scale represents a 10-fold increase in the magnitude of an earthquake. In other words, numbers on the Richter scale are proportional to the common (base 10) logarithms of …

Magnitude scales can be used to describe earthquakes so small that they are expressed in negative numbers. The scale also has no upper limit. Learn more about how we measure earthquake magnitude.

With an isoseismal map of the observed intensities (see illustration) an earthquake's magnitude can be estimated from both the maximum intensity observed (usually but not always near the epicenter), …

Magnitude is the size of the earthquake. An earthquake has a single magnitude. The shaking that it causes has many values that vary from place to place based on distance, type of surface material, …