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geology

(Encyclopedia)geology, science of the earth's history, composition, and structure, and the associated processes. It draws upon chemistry, biology, physics, astronomy, and mathematics (notably statistics) for suppor...

joint, in geology

(Encyclopedia)joint, in geology, fracture in rocks along which no appreciable movement has occurred (see fault). Nearly vertical, or sheet, joints that result from shrinkage during cooling are commonly found in ign...

conglomerate, in geology

(Encyclopedia)conglomerate, in geology, sedimentary rock composed largely of pebbles or other rounded particles whose diameter is larger than 2 mm (.08 in.). Essentially a cemented gravel, conglomerates are formed ...

butte, in geology

(Encyclopedia)butte, an isolated hill with steep sides and a flat top, resulting from the more rapid erosion of the surrounding areas. Buttes are characteristic of the plains of the W United States. See mesa. ...

boulder, in geology

(Encyclopedia)boulder, large rock fragment formed by detachment from its parent consolidated rock by weathering and erosion. In engineering and geology, especially in the United States, the term is applied to loose...

mesa, in geology

(Encyclopedia)mesa māˈsə [key] [Span.,=table], name given in the SW United States to a small, isolated tableland or a flat-topped hill. Two or more of the sides are steep and usually perpendicular and some have ...

spring, in geology

(Encyclopedia)spring, in geology, natural flow of water from the ground or from rocks, representing an outlet for the water that has accumulated in permeable rock strata underground. Some of the water that falls as...

earth, in geology and astronomy

(Encyclopedia)CE5 A. Cross section of the earth, showing its shells B. Detailed cross section of the crust and upper mantle: The lithosphere consists of the hard rock in the crust and upper mantle, lying above t...

Geikie, Sir Archibald

(Encyclopedia)Geikie, Sir Archibald gēˈkē [key], 1835–1924, British geologist, educated at the Univ. of Edinburgh. He joined the Geological Survey of Scotland, becoming its director in 1867. He was professor o...

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