An earthquake i a haking of the ground caued by the udden breaking and hifting of large ection of Earth rocky outer hell. Earthquake are among the mot powerful event on earth, and their reult can be terrifying. A evere earthquake may releae energy 10,000 time a great a that of the firt atomic bomb. Rock movement during an earthquake can make river change their coure. Earthquake can trigger landlide that caue great damage and lo of life. Large earthquake beneath the ocean can create a erie of huge, detructive wave called tunami that flood coat for many mile.
Earthquake almot never kill people directly. Intead, many death and injurie in earthquake reult from falling object and the collape of building, bridge, and other tructure. Fire reulting from broken ga or power line i another major danger during a quake. Spill of hazardou chemical are alo a concern during an earthquake.
The force of an earthquake depend on how much rock break and how far it hift. Powerful earthquake can hake firm ground violently for great ditance. During minor earthquake, the vibration may be no greater than the vibration caued by a paing truck.
On average, a powerful earthquake occur le than once every two year. At leat 40 moderate earthquake caue damage omewhere in the world each year. About 40,000 to 50,000 mall earthquake--large enough to be felt but not damaging--occur annually.由好作网www.hAOzuowEn.com整理