Tertiary period


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Tertiary period

a period of the Cenozoic era lasting from 65 million years ago until the beginning of the Quaternary, 2 million years ago. This is the period of the emergence of mammals, following the extinction of the DINOSAURS.
References in periodicals archive ?
Lyell planned to devote a concluding second volume of Principles of Geology to his reconstruction of the Tertiary period, which he calibrated on the basis of changing mollusk faunas.
Finally, in June 2005, a geology class from University of Alaska Fairbanks stumbled upon a large footprint in Cantwell formation--a layer of rock nearly 8,000 meters thick that was originally thought to have formed in the Tertiary period, after the mass extinction of dinosaurs.
Oil shale belongs to Tertiary Period, the Fisher Assay oil yield accounts for about 7 %.
Although the sampling intensity from time to time and place to place could bias our knowledge on the existant biodiversity during different periods of the Phanerozoic Era, the fossil record of nonmarine tetrapods from the Devonian era (approximately 400 million years ago) onward exhibits an average of about 50 families until the last quarter of the Cretaceous period, when the number of families increased to nearly 80; the rise continued to the present 337 families in several steps in the Tertiary period (2).
This brings us up to the Tertiary period beginning 65 million years ago, when the sea retreated and the county became mainly temperate, interrupted by three glacial periods and a sub-tropical period when crocodiles and hippopotami swam in what was to become the River Avon and other areas such as the centre of Coventry.
Guide books tell you it was created by volcanic activity during the Tertiary period.
He turned the pages back through time, past ancient cities, past the great Ice Age, past the Tertiary period when giant mammals roamed the plains, and past the Cretaceous period when Tyrannosaurus rex prowled.
Spectrum President Dale Henry points out , "The Ancient Rivers of Gold in northern California are from the Tertiary Period.
Charles Darwin and others have assumed that the diversity of marsupial species in Australia reflects the absence of competition from placental mammals during the early Tertiary period.

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