“On-the-Rocks” Field Trip to the Florissant Fossil Beds

Title: “On-the-Rocks” Field Trip to the Florissant Fossil Beds

Trip Leader: Dr. Emmett Evanoff, University of Colorado Museum, Boulder

Date: May 19, 2001

Publication: The Outcrop, May/June 2001, p. 10

Florissant Fossil Beds National Monument contains some of the worlds best known late Eocene insect and plant fossils. This ancient biota has recently been in the center of a controversy between those who believe the flora shows late Eocene elevations to be lower than the modern elevations and those who believe the late Eocene elevations to be the same or higher than the modern elevations. Less known are the geologic details of the fossil-bearing rocks. In this field trip, we will examine the geologic setting of the area and the details of the sediments of the Florissant Formation. Much of this geologic information is only beginning to be published. As we will see, the geology of the formation and the surrounding area gives clues to the nature of the elevation controversy.

Field trip participants will meet at the Park ‘n Ride at Yosemite and East Caley Ave. at 7:45 a.m. for an 8:00 a.m. departure. Take 1-25 to Arapahoe Road. Go west one block to Yosemite and north to Caley Ave. Participants are responsible for their own food and drink, as well as dressing appropriately (layered clothing) for weather and field conditions in May. The Monument is at approximately 8200 feet elevation, so be prepared for cool weather and possible showers. The trip will involve about one mile of walking on relatively flat terrain. For reservations call Bill Cole at 303-789-2750.