❓ why
Why do earthquakes release energy in waves that arrive at different times?
ScienceEarthquakes
Quick Answer
Different seismic waves travel at different speeds and through different parts of the Earth, so they reach stations in a set order.
The Full Story
When a fault ruptures, it sends out several kinds of seismic waves. P waves, or primary waves, are the fastest and arrive first; S waves follow, and surface waves usually arrive later but can cause the strongest shaking. This timing difference helps seismologists locate an earthquake's epicentre and estimate its size. The method has been central to earthquake science since the early 20th century.
Key Facts
1.P waves arrive before S waves
2.Surface waves often cause the strongest shaking
3.Wave timing helps locate the epicentre
YouTube Angle
Suggested video title for this topic:
"Why do quakes send out a first wave, then a second one?"