THE HANKSVILLE-BURPEE QUARRY: A NEW DINOSAUR BONEBED FROM THE BRUSHY BASIN MEMBER, MORRISON FORMATION (LATEST JURASSIC) OF EASTERN UTAH

The late Jurassic Morrison Formation is world famous for its diverse vertebrate fauna, particularly dinosaurs. Notable dinosaur quarries include: Dinosaur National Monument, the Cleveland-Lloyd Quarry, Como Bluff, and the Mygatt-Moore Quarry. In the summer of 2007, a field crew from the Burpee Museum of Natural History was directed by a local Bureau of Land Management geologist to a location where dinosaur bones had been eroding from the outcrops for many years. In the few days available to search the site, many well preserved dinosaur bones were discovered, including sauropod scapulae, limb elements, and partially articulated vertebrae. Subsequent excavations in the summer of 2008 have revealed that the site, designated as the Hanksville-Burpee Quarry, is a dinosaur bone bed measuring at least 100 meters wide by ~400 meters long. The first six week field season uncovered over 150 bones from at least six different dinosaur taxa (some displaying partial articulation) including: Camarasaurus, Diplodocus, Stegosaurus, Allosaurus and possibly Brachiosaurus and Barosaurus. Other interesting features of the site include numerous large petrified logs, possible mammal burrows, and abundant unionid bivalves. A preliminary analysis of the geology, taphonomy and vertebrate paleontology of the site indicates that this quarry represents a series of sand bars in a braided river system, upon which dinosaur carcasses were washed. Subsequent flooding then buried the remains. Due to the size of the site, diversity of taxa present, and the good preservation of the vertebrate material, the Hanksville-Burpee Quarry has considerable long term research potential.