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blasting

(Encyclopedia)blasting, shattering, breaking, or splitting of rock or other material by the discharge of an explosive placed within or in contact with it. It is a necessary part of many engineering operations. An a...

moraine

(Encyclopedia)moraine mərānˈ [key], a formation composed of unsorted and unbedded rock and soil debris called till, which was deposited by a glacier. The till that falls on the sides of a valley glacier from the...

kettle

(Encyclopedia)kettle, oval depression found in glacial moraines, which are landforms made up of rock debris. When a glacier melts and draws away from an area, a block of ice may break off and be covered by earth an...

petroleum

(Encyclopedia)petroleum, oily, flammable liquid that occurs naturally in deposits, usually beneath the surface of the earth; it is also called crude oil. It consists principally of a mixture of hydrocarbons, with t...

cleavage

(Encyclopedia)cleavage, tendency of many minerals to split along definite smooth planar surfaces determined by their crystal structure. The directions of these surfaces are related to weaknesses in the atomic struc...

Lewis, Jerry Lee

(Encyclopedia)Lewis, Jerry Lee, 1935–2022, American singer and composer, b. Ferriday, La. Combining country music elements with an energetic performance style, he w...

gravel

(Encyclopedia)gravel, particles of rock, i.e., stones and pebbles, usually round in form and intermediate in size between sand grains and boulders. Gravel is composed of various kinds of rock, the most common const...

Puy-en-Velay, Le

(Encyclopedia)Puy-en-Velay, Le lə püēˈ-äN-vəlāˈ [key], city (1990 pop. 23,434), capital of Haute-Loire dept., S central France. Le Puy-en-Velay is the center of an old lace industry, as well as traditional ...

basalt

(Encyclopedia)basalt bəsôltˈ, băsˈôlt [key], fine-grained rock of volcanic origin, dark gray, dark green, brown, reddish, or black in color. Basalt is an igneous rock, i.e., one that has congealed from a molt...

Antofagasta

(Encyclopedia)Antofagasta äntōfägäˈstä [key], city, capital of Antofagasta region, N Chile, a port on the Pacific Ocean. Antofagasta was founded by Chileans in 1870 to exploit nit...