This fossil leaf is from the Populus family, a group of trees that includes aspens and cottonwoods. It was uncovered in the rocks of the Green River Formation in Utah. This formation developed over 40 million years ago in deposits that are the...
The Green River Formation, an area extending through Wyoming, Colorado and Utah, is known throughout the world for its excellent preservation of fossils. This formation developed over 40 million years ago in deposits that are the remains of large...