Welcome to Eocene Florissant

Welcome to Eocene Florissant! You've traveled back into the past. In a way, fossils do the same for scientists. We can learn a lot about the past through fossils. Enjoy different activities to learn more about Eocene Florissant.

Dynamic Earth

You made it! The "Time Machine" has transported you into the past. You went from looking at a vast valley to an expansive lake and forest. If you look towards the southwest, you'll notice a looming volcanic complex, which is a collection of similar types of volcanoes.

The climate is entirely different too. Climate is the long-term average of the weather you see in an area. Instead of a drier and cooler environment, the air in Eocene Florissant is warmer and humid. This sustains a different ecosystem (living community of plants and animals), than what you see in present-day central Colorado. The reason for this is because the Earth has gone through many climate changes in its past.

Read about why the present and past climate of Florissant is so different and how rocks and fossils record the past.

 

A view of the lake, forest with Redwoods, and the looming volcanoes of Eocene Florissant.

NPS / Karen Ceballos

 

Changing Times

Earth has gone through many climate changes in its past. Some time between the Eocene (34 million years ago) and Oligocene (23 million years ago), there was a major climatic change specifically a cooling event. This was caused by new cold ocean currents that were the result of tectonic plate (a rigid slab of rock) movement around Antarctica. This cooling event had a devastating impact on the aquatic life and many ancient plants and animals became extinct or died off.

 

Florissant Fossil Beds Stratigraphic Column.

NPS

Rocks Tell a Story

We know what the past environment was like by observing the types of rocks and fossils in the area. For instance, the bottom of the ancient lake is indicated by shale outcrops, which is a type of sedimentary rock (made up of smaller broken up pieces) that contains different fossils like fossilized fish. Evidence of the volcanism is shown by various volcanic rocks and deposits such as the volcanic mudflows or lahars.

We know there once was an ancient forest of various trees and vegetation surrounding the ancient lake because of the petrified wood and fossilized insects, leaves and flowers seen as carbon compression fossils that formed at the bottom of the lake. In carbon compression fossils, the carbon from the ancient animal or plant leaves behind a residue, which shows the organism's original features. Further evidence of the ancient animals are seen as permineralized or petrified bone and teeth fragments in stream deposits of the Lower Mudstone Unit in the Florissant Formation.

By the way, if you're hungry and want to learn more about the rock layers of Florissant Fossil Beds, you might also like to check out the Florissant Enchiladas!

 

There's plenty to see in Eocene Florissant while you're on your virtual adventure!

To begin, choose where you want to go below.