Pacific Ocean, largest and deepest of the world's four oceans, covering more
than a third of the earth's surface and containing more than half of its free
water. It is sometimes divided into two
nominal sections: the part north of the equator is called the North Pacific;
the part south of the equator, the South Pacific. The name Pacific,
which means peaceful, was given to it by the Portuguese navigator Ferdinand
Magellan in 1520.
I BOUNDARIES AND SIZE The Pacific Ocean is bounded on the east
by the North and South American continents; on the north by the Bering Strait;
on the west by Asia, the Malay Archipelago, and Australia; and on the south by
Antarctica. In the southeast it is arbitrarily divided from the Atlantic Ocean by the Drake
Passage along 68° west longitude; in the southwest, its separation from the Indian Ocean is not officially designated. Apart from the
marginal seas along its irregular western rim, it has an area of about 165
million sq km (about 64 million sq mi), substantially larger than the entire
land surface of the globe. Its maximum length is about 15,500 km (about 9600
mi) from the Bering Strait to Antarctica, and its greatest width is about
17,700 km (about 11,000 mi) from Panama
to the Malay Peninsula. Its average depth is
4282 m (14,049 ft). The greatest known depth in any of the world's oceans is
11,033 m (36,198 ft) in the Mariana Trench off Guam.
II RESOURCES Much of the plant and animal life of the Pacific
Ocean is concentrated along its margins. Nutrient-rich waters from
the deep Antarctic Circumpolar Current upwell to the surface in the Peru
Current along the coast of Chile
and the area sustains a large population of anchovetas that is of great
importance as a world food resource. A large guano industry has been established
from droppings of the seabirds that feed upon the anchovetas. The northwestern
Pacific, including the Sea of Japan (East Sea) and the Sea of Okhotsk,
is another major world fishery. Coral reefs rich with sea life reach their peak
in the Great Barrier Reef, which extends for about 2010 km (about 1250 mi)
along the northeastern coast of Australia.
Tuna is another important Pacific resource, bringing fleets of many nations in
search of the schools that migrate over much of the ocean. The Pacific has also
begun to be exploited for its vast mineral resources. The continental shelves
off the coasts of California, Alaska, China,
and the Indonesian area are known to contain large reserves of petroleum.
Patches of the ocean floor are covered with 'manganese nodules,'
potato-sized concretions of iron and manganese oxides that sometimes also
contain copper, cobalt, and nickel. Programs are under way to examine the
feasibility of mining these deposits.