This 8 minute video uses the analogy of a lightbulb to explain the how an earthquake can have different intensities at different places. Magnitudes are based on a logarithmic scale (base 10). What ...

Earthquake Magnitude Scale Magnitude Earthquake Effects Estimated Number Each Year 2.5 or less Usually not felt, but can be recorded by seismograph. Millions 2.5 to 5.4 Often felt, but only causes ...

Magnitude is a measurement of the strength of an earthquake. Officially it's called the moment magnitude scale. It's a logarithmic scale, meaning each number is 10 times as strong as the one ...

The logarithmic earthquake magnitude scale used relatively high-frequency data from nearby seismograph stations, according to the USGS, but as more stations were installed around the world ...