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Jurassic period

(Encyclopedia)Jurassic period jərăsˈĭk [key] [from the Jura Mts.], second period of the Mesozoic era of geologic time, lasting from 213 to 144 million years ago. At the start of the Jurassic most of the contine...

tide

(Encyclopedia)tide, alternate and regular rise and fall of sea level in oceans and other large bodies of water. These changes are caused by the gravitational attraction of the moon and, to a lesser extent, of the s...

sirenian

(Encyclopedia)sirenian sīrēˈnēən [key] or sea cow, name for a large aquatic mammal of the order Sirenia. Living sirenians are the dugong and the manatee, both found in warm, shallow waters in sheltered regions...

Iquique

(Encyclopedia)Iquique ēkēˈkā [key], city (1990 est. pop. 148,500), capital of Iquique prov., N Chile. A port on the Pacific, it exports nitrates and ore from the Atacama Desert. The city, founded in the 16th ce...

seafloor spreading

(Encyclopedia)CE5 Schematic model of the oceanic crust, showing seafloor spreading seafloor spreading, theory of lithospheric evolution that holds that the ocean floors are spreading outward from vast underwate...

transcontinental railroad

(Encyclopedia)transcontinental railroad, in U.S. history, rail connection with the Pacific coast. In 1845, Asa Whitney presented to Congress a plan for the federal government to subsidize the building of a railroad...

mangrove

(Encyclopedia)mangrove, large tropical evergreen tree, genus Rhizophora, that grows on muddy tidal flats and along protected ocean shorelines. Mangroves are most abundant in tropical Asia, Africa, and the islands o...

Melanesia

(Encyclopedia)Melanesia mĕlənēˈzhə, –shə [key], one of the three main divisions of Oceania, in the SW Pacific Ocean, NE of Australia and S of the equator. Melanesia includes the Solomon Islands, Vanuatu, Ne...

Guerrero

(Encyclopedia)Guerrero, state, 24,887 sq mi (64,457 sq km), S Mexico, on the Pacific Ocean. The capital is Chilpancingo. Dominated by the Sierra Madre del Sur, which ...

sea

(Encyclopedia)sea, term used as synonymous with ocean, or a subdivision of an ocean (Caribbean Sea, Yellow Sea), or erroneously designating a large salt lake (Caspian Sea, Dead Sea, Aral Sea). ...