Tertiary

A geological era that began following the extinction of the dinosaurs 66 million years ago and continued until the first ice age began 2.6 million years ago.

The name Tertiary was introduced by Italian geologist Giovanni Arduino in 1760. Arduino categorized sedimentary deposits into three levels: Primary, Secondary, and Tertiary. The Primary level was later renamed the Paleozoic (old life) in line with Darwinian views. Arduino's Secondary level is now referred to as the Mesozoic (middle life). As a remnant of pre-Darwinist geology, the Tertiary has provoked fierce opposition in recent years from the International Commission on Stratigraphy and others. However, the U.S. Geological Society continues to recognize the period.^[1]

References

â Division of Geologic Time -- Major Chronostratigraphic and Geochronological Units, USGS, 2010. "Although the Tertiary is not recognized by many international time scales, the GNC agrees that it is important that it be recognized as a system/period; the map symbols âTâ (Tertiary) and âQâ (Quaternary) have been used on geologic maps for more than a century and are widely used today."

[1] â Division of Geologic Time -- Major Chronostratigraphic and Geochronological Units, USGS, 2010. "Although the Tertiary is not recognized by many international time scales, the GNC agrees that it is important that it be recognized as a system/period; the map symbols âTâ (Tertiary) and âQâ (Quaternary) have been used on geologic maps for more than a century and are widely used today."

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