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slate

(Encyclopedia)slate, fine-grained rock formed when sedimentary rocks such as shale are metamorphosed by great pressure. Slate splits into perfectly cleaved, broad thin layers; this characteristically regular and pl...

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 ...

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 ...

batholith

(Encyclopedia)batholith, enormous mass of intrusive igneous rock, that is, rock made of once-molten material that has solidified below the earth's surface (see rock). Batholiths usually are granitic (see granite) i...

Joplin, Janis

(Encyclopedia)Joplin, Janis jŏpˈlĭn [key], 1943–70, American blues-rock singer, b. Port Arthur, Tex. After dropping out of college (1963) and singing folk rock in Texas clubs, she moved (1966) to San Francisco...

dolomite

(Encyclopedia)dolomite dōˈləmītˌ, dŏlˈə– [key]. 1 Mineral, calcium magnesium carbonate, CaMg (CO3)2. It is commonly crystalline and is white, gray, brown, or reddish in color with a vitreous to pearly lus...

Partch, Harry

(Encyclopedia)Partch, Harry, 1901–74, American composer, b. Oakland, Calif. Highly individualistic and largely self-taught, Partch rejected many of the traditions of Western music. He developed a theory of “cor...

Old Man of the Mountain, rock formation, United States

(Encyclopedia)Old Man of the Mountain, N.H.: see Franconia Mountains. ...

Sela

(Encyclopedia)Sela or Selah sēˈlə [key] [Heb.,=rock], in the Bible, unidentified town, S of the Dead Sea. Amaziah captured it and renamed it Joktheel. Some identify Sela with Petra. Sela in the first chapter of ...