# Comparing earthquakes

That just means that if you add 1 to an earthquake's magnitude, you multiply the shaking by Vibrations similar to the passing of a truck.

## On average, how many 2.0 magnitude earthquakes occur each year?

So-called moment magnitudes, used since the s, are based on a more complicated formula but were designed to be comparable for most earthquakes. Felt quite noticeably by persons indoors, especially on upper floors of buildings. News stories about the disaster in Japan bandy around two sorts of figures when comparing earthquakes: magnitude and energy. Some dishes, windows broken. Vibrations similar to the passing of a truck. An earthquake of magnitude 5 shakes 10 times as violently as an earthquake of magnitude 4; a magnitude-6 quake shakes 10 times as hard as a magnitude-5 quake; and so on. Lines of sight and level are distorted. Another common approach is to talk about the relative amounts of energy they release. You can learn a lot more at the U. Fractional differences work the same way.

Damage great in poorly built structures. Geological Survey's earthquake site. The magnitude scale is logarithmic. From The Severity of an Earthquake.

The old Richter magnitudes, which aren't used anymore, were calculated from ground movements the amplitudes of seismic waves. Pendulum clocks may stop. Shaking isn't the only way to compare earthquakes.

Rated 7/10
based on 74 review

Download