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A:Earthquakes can strike any location at any time. But history shows they occur in the same general patterns year after year, principally inthree large zones of the earth. The world's greatest earthquake belt, thecircum-Pacific seismic belt, is found along the rim of the Pacific Ocean, where about 81 percent of the world's largest earthquakes occur. The belt extends from Chile, northward along the South American coast through Central America, Mexico, the West Coast of the United States, and the southern part of Alaska, through the Aleutian Islands to Japan, the Philippine Islands, New Guinea, the island groups of the Southwest Pacific, and to New Zealand. This earthquake belt was responsible for 70,000 deaths in Peru in May 1970, and 65 deaths and a billion dollars' damage in California in February 1971.Why do so many earthquakes originate in this belt? This is a region of young, growing mountains and deep ocean trenches which invariably parallel mountain chains. Earthquakes necessarily accompany elevation changes in mountains, the higher part of the earth's crust, and changes in the ocean trenches, the lower part. The second important belt, theAlpide, extends from Java to Sumatra through the Himalayas, the Mediterranean, and out into the Atlantic. This belt accounts for about 17 percent of the world's largest earthquakes, including some of the most destructive, such as the Iran shock that took 11,000 lives in August 1968, and the Turkey tremors in March 1970 and May 1971 that each killed over 1,000. All were near magnitude 7 on the Richter scale. The third prominent belt follows the submergedmid-Atlantic Ridge.
The remaining shocks are scattered in various areas of the world. Earthquakes in these prominent seismic zones are taken for granted, but damaging shocks occur occasionally outside these areas. Examples in the United States are New Madrid, Missouri, and Charleston, South Carolina. Many years, however, usually elapse between such destructive shocks.

A: Since 1900, the earthquake inChile on May 22, 1960, is the biggest in the World with magnitude 9.5 Mw.

A: Since 1900, the earthquake inAlaska on March 28, 1964, is the biggest earthquake in the United States, with magnitude 9.2 Mw. This earthquake is also the second biggest earthquake in the World.

A:Alaska andCalifornia.

A: California.

A:Florida andNorth Dakota.

A: Antarctica has the least earthquakes of any continent, but small earthquakes can occur anywhere in the World.

A:

A:SeePast Earthquakes.

A:Most Destructive Earthquakes in the World

A:Ten Largest Earthquakes in the U.S.

A:Ten Largest Earthquakes in the U.S.

A:Earthquake Lists

A:SeePast Earthquakes.