“Quaternary”的概念、定义、翻译、参考文献-科学参考

Quaternary

Biology

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 ago.

Geology and Earth Sciences

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, as formal names. Quaternary researchers objected strongly, so that name (but not Tertiary) has been retained, commencing either 2.588 Ma ago at the start of the Gelasian stage (2.588–1.806 Ma ago) or about 3.6 Ma ago at the start of the preceding Piacenzian stage (3.6–2588 Ma ago).

Geography

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

单词	Quaternary
释义	Quaternary Biology 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 ago. Geology and Earth Sciences 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, as formal names. Quaternary researchers objected strongly, so that name (but not Tertiary) has been retained, commencing either 2.588 Ma ago at the start of the Gelasian stage (2.588–1.806 Ma ago) or about 3.6 Ma ago at the start of the preceding Piacenzian stage (3.6–2588 Ma ago). Geography The most recent period of geological time, covering the last 2 million years, and including the Pleistocene and the Holocene.
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