EARTHQUAKES occur when the earth's crust suddenly moves along a fault. Most quakes are so slight that they are not felt by humans.
EARTHQUAKES occur when the earth's crust suddenly moves along a fault. Most quakes are so slight that they are not felt by humans.
Some quakes create vibrations similar to those caused by the passing of a large truck. But vibrations of big earthquakes can be extremely destructive; they can destroy entire cities in seconds. - sciencekids.co.nz; pacificislandtravel.com; wikipedia.org