How to Measure Earthquakes
For daily wit & wisdom, sign up for the Almanac newsletter.
Body
Wondering how earthquakes are measured? Seismologists have developed a new measurement of earthquake size, called the Moment Magnitude.
All earthquakes can now be compared on the same scale with the Moment Magnitude. Previously, the Richter scale was used, however, it is precise only for measuring earthquakes of a certain size and at a certain distance from a seismometer.
See the Moment Magnitude chart below.
| Magnitude |
Effect |
| Less than 3 |
Micro |
| 3–3.9 |
Minor |
| 4–4.9 |
Light |
| 5–5.9 |
Moderate |
| 6–6.9 |
Strong |
| 7–7.9 |
Major |
| 8 or more |
Great |
About The Author
Heidi Stonehill
Heidi Stonehill is the executive editor for The Old Farmer’s Almanac, where she focuses much of her time on managing content development for the Almanac’s line of calendars.
Read More from Heidi Stonehill
