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wave, in the earth sciences

(Encyclopedia)CE5 A. Diagram of wave: Wave travels one wavelength during one period B. Diagram of wave: Phase relationships wave, in oceanography, an oscillating movement up and down, of a body of water caused ...

diatomaceous earth

(Encyclopedia)diatomaceous earth: see diatom.

Earth Day

(Encyclopedia)Earth Day, Apr. 22, a day to celebrate the environment. The first Earth Day was organized in 1970 to promote the ideas of ecology, encourage respect for life on earth, and highlight growing concern ov...

earth goddess

(Encyclopedia)earth goddess: see Great Mother Goddess. ...

earth pig

(Encyclopedia)earth pig: see aardvark.

Earth Summit

(Encyclopedia)Earth Summit: see United Nations Conference on Environment and Development. ...

fuller's earth

(Encyclopedia)fuller's earth, mineral substance characterized by the property of absorbing basic colors and removing them from oils. It is composed mainly of alumina, silica, iron oxides, lime, magnesia, and water,...

snowball earth

(Encyclopedia)snowball earth, hypothesized condition in which the earth was covered completely by ice during several periods in the Proterozoic. The hypothesis was originally developed to explain evidence of the co...

black earth

(Encyclopedia)black earth: see chernozem.

rammed earth

(Encyclopedia)rammed earth, material consisting chiefly of soil of sufficiently stiff consistency that has been placed in forms and pounded down. It has been used for buildings and walls since ancient times and was...