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 ...

These scales account for the distance between the earthquake and the recording seismometer so that the calculated magnitude should be about the same no matter where it is measured. Another scale is ...

The moment magnitude scale (MMS; denoted explicitly with Mw or Mw, and generally implied with use of a single M for magnitude) is a measure of an earthquake's magnitude ("size" or strength) based on ...

One of the most commonly known earthquake-measuring tools is the Richter Scale, but the system is no longer used today. In fact, the Richter scale was replaced in the 1970s by other magnitude ...

A light, 4.7-magnitude earthquake ... on the Modified Mercalli Intensity scale. When aftershock data is available, the corresponding maps and charts include earthquakes within 100 miles and ...