* P-waves (Primary Waves): These are compressional waves, meaning they cause particles to move back and forth in the same direction as the wave travels. They are the fastest seismic waves and can travel through solids, liquids, and gases.
* S-waves (Secondary Waves): These are shear waves, meaning they cause particles to move perpendicular to the direction of wave travel. They are slower than P-waves and can only travel through solids.
Both P-waves and S-waves travel through the Earth's mantle.
Here's how it works:
* Focus: Earthquakes originate at a point underground called the focus.
* Epicenter: The point on the Earth's surface directly above the focus is called the epicenter.
* Seismic waves radiate outwards: From the focus, both P-waves and S-waves travel outward in all directions.
* Mantle journey: These waves travel through the Earth's mantle, a layer of hot, dense rock that extends from the crust to the outer core.
* Changes in speed and direction: As the waves travel through the mantle, they change speed and direction based on the density and composition of the mantle rocks.
Therefore, all earthquakes, regardless of their magnitude, generate P-waves and S-waves that travel through the Earth's mantle.
