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Carboniferous period

(Encyclopedia) Carboniferous period krb?n?f?r?s, fifth period of the Paleozoic era of geologic time (see Geologic Timescale, table), from 350 to 290 million years ago. Historical Geology of the?

How Old Is the Grand Canyon?

The Grand Canyon may be 10 million years older than we thought by Liz Olson Visit our Grand Canyon Slideshow.Photo of the Grand Canyon courtesy of Carol M. Highsmith?