Pacific Ocean, world's largest and deepest ocean, extending from the Arctic to the Antarctic oceans and from the Americas to Asia, covering an area of about 70 million sq mi (181.3 million sq km), or one-third of the earth's total surface. The average depth of the Pacific is 14,000 ft (4,267 m); the deepest point is 36,198 ft (11,033 m) in the Challenger Deep, in the Marianas Trench, southwest of Guam. Plateaus, ridges, trenches, and sea mountains make for many variations in depth. Japan, the Philippines, New Zealand, and thousands of islands lie on the connected series of ridges running from the Bering Straits southwest to the South China Sea. Despite its name, the ocean is not generally calm. In the tropical and subtropical zones an average of more than 130 cyclones occur per year.
21st Century Webster's Family Encyclopedia21st Century Webster's Family Encyclopedia - Olympic Mountains to Palermo