Green River Formation

The Green River Formation spreads over parts of Wyoming, Utah, and Colorado. The rocks and fossils found in the Green River formation date back to the Eocene epoch (about 50 million years ago), and the layers of rock found there represent about 6 million years of sediment deposition. The rock is made of a fine-grained limestone believed to be formed on the bottom of an ancient lakebed.

Earth Experience'‘s Green River Fish Wall exhibit

The Green River Formation is known for its incredibly well-preserved fossils. Most fossils from Green River are fish, but there are also rarer instances of birds, reptiles, plants, insects, horses, and the earliest known bat species ever discovered.

Photo courtesy of Joe Nochera

The matrix (or rock that the fossils are imbedded in) is cut straight from the ground in fossil quarries like the one pictured here. Typically, small amounts of fossil poke out, telling paleontologists there is more beneath the surface. In the video below, you can see how the plates are cut down into smaller pieces after quarrying. The fossils are then carefully prepared and displayed. Some of these fossils pictured here were prepared in Earth Experience’s Paleo Lab!

Video courtesy of Joe Nochera