Florissant Formation (Colo.)

found: Work cat.: Paleontology of the Upper Eocene Florissant Formation, Colorado, 2008.

found: National Park Service WWW page, Jul. 9, 2008:(Florissant Formation; formed in association with a series of volcanic eruptions from the Guffey volcanic center, which is part of the Thirtynine Mile volcanic field and is located approximately 18 miles southwest of the Florissant Fossil Beds National Monument)

found: Encyclopaedia Britannica online, Jul. 9, 2008(Florissant Formation, geology, division of middle and upper Oligocene rocks in central Colorado, U.S. (The Oligocene Epoch lasted from 33.7 to 23.8 million years ago))