Science & Earth · Updated September 2026
Earthquake facts
Earthquakes happen when rocks slip along a fault. Magnitude measures size; intensity measures shaking at a place. Epicentre vs hypocentre, and why the Pacific “Ring of Fire” appears in every quiz.
An earthquake is a sudden slip of rock along a fault. Energy travels as seismic waves. The hypocentre (focus) is where the slip starts underground. The epicentre is the point on the surface above it — the name you see on news maps.
Magnitude is a single number for the event’s size (modern scales are moment magnitude; “Richter” is the old popular word). Intensity (Mercalli) describes how hard a given town shook. A magnitude 7 far away can feel weaker than a magnitude 5 under a city.
Most large quakes sit on plate boundaries. The Pacific Ring of Fire is the most cited belt. Quakes cannot be predicted to the day. Building codes and drop-cover-hold save more lives than rumours.
Earthquake facts — key facts (2026)
| Topic | Fact |
|---|---|
| Focus / hypocentre | Underground start point |
| Epicentre | Surface point above the focus |
| Modern size scale | Moment magnitude (Mw) |
| Intensity scale | Modified Mercalli (shaking at a place) |
| Instrument | Seismometer / seismograph |
| Common belt | Pacific Ring of Fire |
| Aftershock | Smaller quake after a main shock |
| Prediction | No reliable day-and-hour forecast |
Figures are the usual classroom and news-desk numbers for 2026. Border disputes and membership votes can change a count by one or two.
People also ask
What is the difference between magnitude and intensity?
Magnitude is one size for the quake. Intensity is how strong the shaking was where you stood.
Can animals predict earthquakes?
There is no method that works well enough for public warnings. Do not wait for a story about dogs.
What should you do in a quake?
Drop, cover and hold on. Stay away from windows and exterior walls if you can. This is safety education, not a live alert service.