Morrison Formation

dinosaurs · geology · fossils · jurassic

Dinosaur treasure chest. The Morrison Formation is the single best place in North America for finding dinosaur bones, with fossils from giants like Brachiosaurus and Stegosaurus hiding in its rocks.

Made of layers. This rock formation is built from mudstone, sandstone, siltstone, and limestone, all squished together over millions of years into different colored stripes of gray, greenish gray, and red.

Ancient rivers and floods. Most of the dinosaur fossils are found in green siltstone and sandstone layers that used to be rivers and floodplains during the Jurassic period, around 150 million years ago.

Western United States. You can find the Morrison Formation spread across the western United States, making it one of the most important places for learning about prehistoric life in North America.