Science | seismic waves and tsunamis

Focus

The exact point inside the Earth where an earthquake originates.

Epicenter

The point on the Earth's surface directly above the focus.

Magnitude

pertains to the strength and the "size" of an earthquake.

Richter Scale

open-ended scale to measure the magnitude of an earthquake

Intensity

measures the observed effects of earthquakes on people, geologic structures, and man-made structures.

P - waves

Causes less damage; mainly felt as a sharp jolt.

S - waves

Causes stronger shaking, leading to building damage.

L - waves

Faster than Rayleigh waves but slower than body waves.

R - waves

Slowest of all seismic waves.

Tsunami

is a series of powerful waves caused by underwater disturbances, moving the entire water column and causing great destruction.