Part 1 of 5 · freeIntroduction
Every year the Earth records about 500,000 earthquakes that instruments can detect. Only a small share cause serious damage. A quake is not random: it is the sudden end of a long build-up of energy inside the rock.
To understand it, picture the surface of the planet as a jigsaw of moving plates. Where those plates rub against each other, the strain rises, until something snaps.
The rest is in the Sophia app.The remaining parts, the open-book quiz and the full glossary. Free to start; Premium unlocks everything.
- 2Plates that never stop moving
- 3When the fault gives way
- 4Measuring the power, fearing the tsunami
- 5Waves, warnings, and buildings that hold
Open-book quiz9 questions whose answers are in the text.
Glossary17 terms explained in a tap.
30 languagesThe same course, from French to Japanese.
