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The Tertiary: a proposal for its formal definition 被引量:1
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作者 Martin J. Head Philip Gibbard amos salvador 《Episodes》 SCIE 2008年第2期248-250,共3页
The term Tertiary, subdivided into the Paleogene and Neogene, is traditionally used to represent the interval of geological time between the Cretaceous and Quaternary. In the 1990s, however, the Neogene and Paleogene ... The term Tertiary, subdivided into the Paleogene and Neogene, is traditionally used to represent the interval of geological time between the Cretaceous and Quaternary. In the 1990s, however, the Neogene and Paleogene were ratified by the International Union of Geological Sciences as periods/systems of the Cenozoic Era/Erathem, leaving the Tertiary officially undefined. The Tertiary nonetheless remains a formal term that has never been officially eliminated, and its widespread use today implies a long future. 展开更多
关键词 地球 第三纪地质时代 清晰度 地质学
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The Quaternary: its character and definition
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作者 Martin J. Head Philip Gibbard amos salvador 《Episodes》 SCIE 2008年第2期234-238,共5页
The Quaternary, is characterised by the development of widespread glaciations in mid-northern latitudes. As a chronostratigraphic term it has attracted vigorous debate. The Quaternao; as accepted by the International ... The Quaternary, is characterised by the development of widespread glaciations in mid-northern latitudes. As a chronostratigraphic term it has attracted vigorous debate. The Quaternao; as accepted by the International Union for Quaternary Research and proposed by the International Commission on Stratigraphy, begins at 2.6 Ma within a 2.8-2.4 Ma interval of profound change in Earth's climate system. 展开更多
关键词 第四纪地质时代 地球 特征 清晰度
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A stable Cenozoic geologic time scale is indispensable
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作者 amos salvador 《Episodes》 SCIE 2006年第1期43-45,共3页
A stable, standard geologic time scale is indispensable for the clear and precise communication among geologists; it is a basic tool of geologic work. Considerable progress has been made to achieve such a stable time ... A stable, standard geologic time scale is indispensable for the clear and precise communication among geologists; it is a basic tool of geologic work. Considerable progress has been made to achieve such a stable time scale. However, during the last few years several proposals have been made to modify the Cenozoic section of the geologic time scale that threaten to destabilize it. Seven articles published in Episodes since 2000 that could contribute to this destabilization are discussed. They provide excellent examples of the profusion of different terminologies, hierarchies, and stratigraphic relationships that have been proposed: to eliminate the Tertiary and the Quaternary or to raise their rank to suberathems; to extend the Neogene to the present; to make the Quaternary a formal subsystem of the Neogene, or consider it an informal stratigraphic unit; to eliminate the Holocene, and to decouple the base of the Pleistocene from the base of the Quaternary. If adopted, these proposals would cause nothing but great confusion and controversy. They disregard the clear preferences of geologists the world over as reflected by the terminology they have been using for many decades. Common sense would dictate the continued use of this terminology in its current, widely accepted form. 展开更多
关键词 新生代 地质时间 比例尺 地质工作
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