Oligocene

Third epoch of the Paleogene Period

The Oligocene is a geologic epoch of the Paleogene Period that extends from about 33.9 million to 23 million years before the present (33.9±0.1 to 23.04±0.05 Ma). As with other older geologic periods, the rock beds that define the epoch are well identified but the exact dates of the start and end of the epoch are slightly uncertain. The name Oligocene was coined in 1854 by the German paleontologist Heinrich Ernst Beyrich from his studies of marine beds in Belgium and Germany.

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