Studies suggest that the paleoenvironment of this part of the Morrison Formation had rivers flowing from the west into a basin with a giant, saline alkaline lake. There were extensive wetlands nearby. Fossils from the Dry Mesa Dinosaur Quarry of western Colorado show one of the most diverse Upper Jurassic vertebrate assemblages in the world. The Dry Mesa Quarry has produced the remains of the sauropods "Apatosaurus", "Diplodocus", "Barosaurus", "Supersaurus", "Dystylosaurus", "Camarasaurus", the iguanodontid "Camptosaurus", and the theropods "Allosaurus", "Ceratosaurus" and "Ornitholestes", as well as "Dryosaurus", and "Stegosaurus".