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Quaternary

The most recent period of geological time, covering the last 2 million years, and including the Pleistocene and the Holocene.

Quaternary

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A Dictionary of Zoology (5 ed.)

Reference type:
Subject Reference
Current Version:
2020
Subject:
Science and technology, Life Sciences
Length:
146 words

...term Quaternary was to have been abandoned. The name is so widely used, however, especially among scientists engaged in Quaternary research, with a scientific journal Quaternary Research published by the Quaternary Research Center and the International Union for Quaternary Science, that the name has been retained. ‘Quaternary’ is now synonymous with ‘Pleistogene’...

Quaternary

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A Dictionary of Genetics (8 ed.)

Reference type:
Subject Reference
Current Version:
2014
Subject:
Science and technology, Life Sciences
Length:
18 words

... the most recent of the two geologic periods making up the Cenozoic era. See geologic time divisions...

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A Dictionary of Geography (5 ed.)

Reference type:
Subject Reference
Current Version:
2015

... ( Pleistogene ) The most recent period of geological time, covering the last 2 million years, and including the Pleistocene and the Holocene...

Quaternary

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A Dictionary of Plant Sciences (4 ed.)

Reference type:
Subject Reference
Current Version:
2019
Subject:
Science and technology, Life Sciences
Length:
125 words

...out of Quaternary in favour of Pleistogene, but the difficulties this would have made for those engaged in Quaternary research led to the retention of the name Quaternary, with Pleistogene as a...

quaternary

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A Dictionary of Weights, Measures, and Units

Reference type:
Subject Reference
Current Version:
2004

... geology . Although etymologically meaning of four parts, the quaternary in the geochronologic scale is the fourth part in sequence of what was originally the Cambrian period. It began 1.5 million years ago and is still continuing; hence it can be taken to mean the current time (its second epoch, the Holocene, being the latest 11 000...

quaternary

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A Dictionary of Construction, Surveying and Civil Engineering (2 ed.)

Reference type:
Subject Reference
Current Version:
2020

... 1. Occurring in fours or consisting of four parts. 2. The present geological period, just over the last 2 million years to the present...

quaternary

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Oxford Dictionary of Biochemistry and Molecular Biology (2 ed.)

Reference type:
Subject Reference
Current Version:
2008
Subject:
Science and technology, Life Sciences
Length:
38 words

... 1 consisting of four (items, parts, etc.); by or in fours. 2 (in chemistry) consisting of or containing an atom bound to four atoms or groups. 3 of the fourth order; fourth in a series or...

Quaternary

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A Dictionary of Geology and Earth Sciences (5 ed.)

Reference type:
Subject Reference
Current Version:
2020

... ( Pleistogene , Anthropogene ) Traditionally, either a sub‐era of the Cenozoic era of geologic time that began 1.806 Ma ago and continues to the present day; it is sometimes known as the Pleistogene period and includes the Pleistocene and Holocene epochs , during which there have been numerous ice‐sheet advances in the northern hemisphere. However, the boundary between the Quaternary and the preceding Tertiary was never clearly defined and the International Commission on Stratigraphy proposed abandoning both terms, Tertiary and Quaternary...

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A Dictionary of Biology (8 ed.)

Reference type:
Subject Reference
Current Version:
2019
Subject:
Science and technology, Life Sciences
Length:
83 words

...Quaternary The second and current period of the Cenozoic era, extending from about 2.58 million years ago, following the Neogene period, to the present. The beginning of the Quaternary was based on the onset of a worldwide cooling. During the period four principal glacial phases occurred in Europe and North America, in which ice advanced towards the equator, separated by interglacials during which conditions became warmer and the ice sheets and glaciers retreated. The last glacial ended about 10 000 years...

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World Encyclopedia

Reference type:
Subject Reference
Current Version:
2004
Subject:
Encyclopedias
Length:
44 words

... Most recent period of the Cenozoic era, beginning c .2 million years ago and extending to the present. It is divided into the Pleistocene epoch, characterized by a periodic succession of great Ice Ages, and the Holocene epoch, which started some 10,000 years...

Quaternary

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The Oxford Companion to the Earth

Reference type:
Subject Reference
Current Version:
2003

...has been the most distinctive biological feature of the Quaternary. The genus Homo , appearing first in Africa, spread rapidly into Eurasia during the early Pleistocene. Migration continued into Holocene time, accompanied by stone-based and more advanced cultures. D. L. Dineley Charlesworth, J. K. (1957) The Quaternary Era . 2 vols. Arnold, London. Imbrie, J. and Imbrie, K. P. (1979) Ice ages: solving the mystery . Macmillan, London. Pomerol, C. (1982) The Cenozoic Era: Tertiary and Quaternary . (Trans. D. and E. E. Humphries .) Ellis Horwood,...

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A Dictionary of Environment and Conservation (3 ed.)

Reference type:
Subject Reference
Current Version:
2017

... ( Pleistogene ) The most recent period of geological time, covering the last 2.588 million years, which includes the Pleistocene and the Holocene...

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A Dictionary of Ecology (5 ed.)

Reference type:
Subject Reference
Current Version:
2015

... Traditionally, either a sub-era or a period of the Cenozoic Era of geologic time that began 1.806 Ma ago and continues to the present day; it is sometimes known as the Pleistogene period and includes the Pleistocene and Holocene epochs, during which there have been numerous ice-sheet advances in the northern hemisphere. However, the boundary between the Quaternary and the preceding Neogene was never clearly defined, and the International Commission on Stratigraphy proposed abandoning all three terms, Tertiary, Quaternary, and Pleistogene, as...

quaternary

quaternary adj. & n.   Reference library

Garner’s Modern English Usage (4 ed.)

Reference type:
Subject Reference
Current Version:
2016

... , adj. & n. , is often misspelled ✳quartenary, ✳quarternary , or ✳quatenary . The adjective means “consisting of four parts,” the noun “a set of four things.” The word is pronounced either / kwah -tәr-ner-ee/ or /kwә- tәr -nәr-ee/...

quaternary industry

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A Dictionary of Geography (5 ed.)

Reference type:
Subject Reference
Current Version:
2015

... industry ( quaternary activity, quaternary sector ) Economic activity concerned with information: its acquisition, manipulation, and transmission. Into this category fall law, finance, education, research, and the media. See D. Ley (1996) on the middle classes and the expansion of quaternary...

quaternary structure

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A Dictionary of Plant Sciences (4 ed.)

Reference type:
Subject Reference
Current Version:
2019
Subject:
Science and technology, Life Sciences
Length:
32 words

... structure The structure of a protein that results from the interaction of two or more individual polypeptides to give larger functional molecules. Compare primary structure ; secondary structure ; tertiary structure...

quaternary structure

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A Dictionary of Zoology (5 ed.)

Reference type:
Subject Reference
Current Version:
2020
Subject:
Science and technology, Life Sciences
Length:
32 words

... structure The structure of a protein that results from the interaction of two or more individual polypeptides to give larger functional molecules. Compare primary structure ; secondary structure ; tertiary structure ....

Quaternary System

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The Concise Oxford Dictionary of Archaeology (2 ed.)

Reference type:
Subject Reference
Current Version:
2009
Subject:
Archaeology, History
Length:
95 words

... System [CP] A major chronostratigraphic subdivision; the latest of the two periods forming the Cenozoic era (the other is the Tertiary ), itself composed of two epochs, the Pleistocene and the Holocene . These terms can be applied to groups of deposits (geostratigraphic subdivisions) as the Quaternary ‘system’ embracing Pleistocene or Holocene ‘series’. The Quaternary System, beginning about 2.4 million years ago, comprises a number of elements that were once seen as a succession of glacial and interglacial episodes. Deep‐sea cores and the...

quaternary system

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A Dictionary of Geology and Earth Sciences (5 ed.)

Reference type:
Subject Reference
Current Version:
2020

... system A mineral system with four components, for example, the four‐component system for diopside (Di)– anorthite (An)– albite (Ab)– pyroxene (Fs), diagrammatically represented as a tetrahedron. See cotectic surface ; phase ; phase diagram...

quaternary structure

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Oxford Dictionary of Biochemistry and Molecular Biology (2 ed.)

Reference type:
Subject Reference
Current Version:
2008
Subject:
Science and technology, Life Sciences
Length:
84 words

... structure the fourth order of complexity of structural organization exhibited by protein, nucleic acid, and nucleoprotein molecules. It refers to the arrangement in space of the subunits of a multimeric macromolecule, and the ensemble of its intersubunit contacts and interactions, without regard to the internal geometry of the subunits. Hence, it is possessed only when the molecule in question is made up of at least two (identical or non‐identical) subunits that are (at least potentially) separable, i.e. are not linked by covalent...

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