Columbia Encyclopedia

(Encyclopedia) Miocene epoch mīˈəsēn [key], fourth epoch of the Tertiary period in the Cenozoic era of geologic time (see Geologic Timescale, tablegeologic timescale, table), lasting from around 24.6 to 5.1 mill...

(Encyclopedia) Aleutian Islands əlo͞oˈshən [key], chain of rugged, volcanic islands curving c.1,200 mi (1,900 km) west from the tip of the Alaska Peninsula and approaching Russia's Komandorski Islands. A partial...

(Encyclopedia) Ryukyu Islands rēo͞oˈkyo͞o [key], Jap. Ryukyu-retto or Nansei-shoto [southwest group], archipelago (1990 est. pop. 1,500,000), c.1,850 sq mi (4,790 sq km), SW Japan, in the W Pacific Ocean. The ch...

(Encyclopedia) Hill, James Jerome, 1838–1916, American railroad builder, b. Ontario, Canada. He went to St. Paul, Minn., in 1856. He became a partner of Norman Kittson in a steamboat line and, with Kittson, Donald...

(Encyclopedia) North Atlantic Drift, warm ocean current in the northern part of the Atlantic Ocean. It is a continuation of the Gulf Stream, the merging point being at lat. 40°N and long. 60°W. Off the British Isl...

(Encyclopedia) Saint Johns, river, 285 mi (459 km) long, rising in SE Fla., N of Lake Okeechobee, and flowing N to Jacksonville, where it turns abruptly eastward and enters the Atlantic Ocean 28 mi (45 km) away. It ...

(Encyclopedia) Guanabara gwänäbäˈrä [key], former state, SE Brazil, on the Atlantic Ocean; since 1974, part of the state of Rio de Janeiro. Guanabara Bay, a deep inlet of the Atlantic Ocean, is noted for its be...

(Encyclopedia) coral reefs, limestone formations produced by living organisms, found in shallow, tropical marine waters. In most reefs, the predominant organisms are stony corals, colonial cnidarians that secrete an...

(Encyclopedia) Kiribati kĭrˌĭbăsˈ [key], officially Republic of Kiribati (2015 est. pop. 112,000), 342 sq mi (886 sq km), consisting of 33 islands scattered across 2,400 mi (3,860 km) of the Pacific Ocean near ...

(Encyclopedia) hydrothermal vent, crack along a rift or ridge in the deep ocean floor that spews out water heated to high temperatures by the magma under the earth's crust. Some vents are in areas of seafloor spread...