Columbia Encyclopedia

Search results

500 results found

fold

(Encyclopedia)fold, in geology, bent or deformed arrangement of stratified rocks. These rocks may be of sedimentary or volcanic origin. Although stratified rocks are normally deposited on the earth's surface in hor...

W and Z particles

(Encyclopedia)W and Z particles, elementary particles that mediate, or carry, the fundamental force associated with weak interactions. The discovery of the W and Z particles at CERN near Geneva, Switzerland, in the...

white dwarf

(Encyclopedia)white dwarf, in astronomy, a type of star that is abnormally faint for its white-hot temperature (see mass-luminosity relation). Typically, a white dwarf star has the mass of the sun and the radius of...

observatory

(Encyclopedia)observatory, scientific facility especially equipped to detect and record naturally occurring scientific phenomena. Although geological and meteorological observatories exist, the term is generally ap...

Smith, William

(Encyclopedia)Smith, William, 1769–1839, English geologist. Through direct observation as a canal-site surveyor, Smith made a systematic study of the geological strata of England and identified the fossils peculi...

epoch

(Encyclopedia)epoch, unit of geologic time that is a subdivision of a period. The Pleistocene and Holocene epochs, for example, are divisions of the Quaternary period. Epoch is also used to describe a short length ...

Anaximander

(Encyclopedia)Anaximander ənăkˌsĭmănˈdər [key], c.611–c.547 b.c., Greek philosopher, b. Miletus; pupil of Thales. He made the first attempt to offer a detailed explanation of all aspects of nature. Anaxima...

era

(Encyclopedia)era, period of historic time. In geology, it is the name applied to large divisions of geological process, e.g., Paleozoic era (see geology). In chronology an era is a period reckoned from a fixed poi...

Communist party, in Russia and the Soviet Union

(Encyclopedia)See L. Schapiro, The Communist Party of the Soviet Union (2d ed. 1971); S. F. Cohen, Rethinking the Soviet Experience (1985); M. Geller, Utopia in Power (1986); S. Carter, Russian Nationalism (1990); ...

plate tectonics

(Encyclopedia)CE5 Plate tectonics: Map of the world showing major plates and plate boundaries CE5 Plate tectonics: Schematic model of the oceanic crust, showing the three types of plate boundaries plate tect...