Dating back to the Eocene Period (54 to 37 million years ago), the Green River fossil beds are one of the most important in the United States of America. The first known excavations in the region took place in the 1850s. In 1856, the archaeologist Dr. John Evans announced the fish fossils he had collected in the region to the scientific world, and the Green River Formation thus entered the scientific literature.
The Green River is actually a tributary of the Colorado River. The Green River Formation itself is a mountain-lake basin consisting of an area spread over three separate states. Part of it lies to the east of the Uinta Mountains in northwest Colorado, and a wider part lies in southwest Wyoming.
Green River's rock structure is made up of different strata, whose contents vary the deeper down one goes. Fossil distribution also varies. To date, fossils belonging to some 60 separate vertebrate groups have been found in digs in Green River and countless invertebrate fossils.
Ohio is a state with well-known fossil fields. Geological research has shown that some 510 million years ago, Ohio lay to the south of Ecuador. As the continents drifted and North America moved towards its present position, Ohio found itself underwater several times. That explains why a large number of fossils dating back to the Palaeozoic (543 to 251 million years ago) have been discovered in Ohio.
Another state with rich fossil beds is Utah. A great variety of fossils, from invertebrates to different marine organisms and from reptiles to mammals, has been unearthed in Utah. Microscopic fossils recently discovered in the Uinta Mountains have revealed that there are fossil beds in Utah dating to the Cambrian Period.
As is the case with fossils discovered in other regions of the world, all of them once again demonstrate that there is no difference between modern-day trout, skate, dragonflies, flies, spiders, crabs and turtles and similar creatures that lived millions of years ago. Living things have undergone no change in the intervening hundreds of millions of years—in other words, they did not undergo evolution. The fossil records refute evolution and once again confirm the fact of creation.