The Earth Crackles
The earth makes crackling noises too, but the cracks are so
big and so long that we don't ever hear them - we feel
them! Have you ever been in an earthquake? Each earthquake is
just a single "crack" in the crackling of the earth!
Here is the sound of one earthquake, the Northridge Earthquake,
sped up by a factor of 100. This
earthquake happened near Los Angeles, in California, in 1994. During
this earthquake, the whole valley probably jumped about an inch (a couple
Only an inch you say? That was enough to knock down bridges!
How do we know the earth crackles? We took an entire YEAR of earthquakes,
and speed them up a whole lot. Each crackle is an earthquake: the early ones
happened in January, and the last ones happened in December.
Doesn't it sound like the crackling of