Multicolored (variegated) beds of the Morrison Formation at Como Bluff, Wyoming. Many historical dinosaur sites are located along the flanks of the bluff. The Sundance Formation is visible as the reddish beds at the base of the bluff.
|Location||taken near Aurora Lake (a.k.a. Como Lake).|
|Nearest city||Rock River-Medicine Bow|
|NRHP Reference #||73001925|
|Added to NRHP||January 18, 1973|
Como Bluff is a long ridge extending east-west, located between the towns of Rock River and Medicine Bow, Wyoming. The ridge is an anticline, formed as a result of compressional geological folding. Three geological formations, the Sundance, the Morrison, and the Cloverly Formations, containing fossil remains from the Late Jurassic of the Mesozoic Era are exposed. Nineteenth century paleontologists discovered many well-preserved specimens of dinosaurs, as well as mammals, turtles, crocodilians, and fish from the Morrison Formation. Because of this, Como Bluff is considered to be one of the major sites for the early discovery of dinosaur remains. Among the species discovered is the only known specimen of Coelurus. Significant discoveries were made in 22 different areas scattered along the entire length of the ridge. It is included on the National Register of Historic Places as well as the National Natural Landmark list.
History of discovery
The discovery of dinosaurs at Como Bluff has been recounted numerous times, most notably by Schuchert and LeVene, Shur, Ostrom and McIntosh, and Jaffe. Most of the specimens were collected by men working for O.C. Marsh between 1877-1889, although some were collected by the Hubbel brothers for E.D. Cope between 1879-1880. The American Museum of Natural History excavated in 1897 -1898 , finding two partial skeletons of sauropods. A summary of the quarries and their contents is given below.
In later years, the American Museum of Natural History and Yale University jointly reopened Quarry 9, the Mammal Quarry, 1968-1970, finding only a few specimens. More recently, Robert Bakker has done some collecting there with a variety of groups.
Como Bluff historical quarries (pre-1900)
AMNH Quarry 1
AMNH Quarry 2
AMNH localities unknown (some could be from Quarry 1 or 2)
[Fredrick] Brown’s Quarry A
Brown’s Quarry B
Brown’s Quarry C
Brown’s Quarry D
Brown’s Quarry G
[Authur] Lakes Quarry 1A (Big Canyon Quarry)
[E.D.] Cope's Quarry 3
Cope's Quarry 4
Cope's Quarry 5
Cope's localities unknown (could be from Quarry 1, 2)
[Harlow] Reed’s Quarry 1
Reed’s Quarry 1 ½
Reed’s Quarry 2
Reed’s Quarry 3
Reed’s Quarry 4
Reed’s Quarry 5
Reed’s Quarry 6
Reed’s Quarry 7
Reed’s Quarry 8
Reed’s Quarry 9 (Mammal Quarry)
Reed’s Quarry 10
Reed’s Quarry 11
Reed’s Quarry 12 (Robbers' Roost Quarry)
Reed’s Quarry 13
Reed Quarry 14
- List of fossil sites (with link directory)
- Schuchert, C., and LeVene, C.M. 1940. O.C.Marsh, Pioneer in Paleontology. Yale University Press, New Haven.
- Shur, E. 1974. The Fossil Feud. Exposition Press, NY. 340p.
- Ostrom, J,H., and McIntosh, J.S. 1966. Marsh's Dinosaurs: The Collections from Como Bluff. Yale University Press, New Haven.
- Jaffe, M. 2000. The Gilded Dinosaur. Crown Publ., New York.
- Prothero, D.R. 1981. New Jurassic mammals from Como Bluff, Wyoming, and the interrelationships of non-tribosphenic Theria. Bulletin of the American Museum of Natural History 167: 281:325
- Ostrom and McIntosh
- Carrano, M.T., and Velez-Juarbe, J. 2006. Paleoecology of the Quarry 9 vertebrate assemblage from Como Bluff, Wyoming (Morrison Formation, Late Jurassic). Palaeogeography, Palaeoclimatology, Palaeoecology 237:147-159.
- Foster, J.R. 2003. Paleoecological analysis of the vertebrate fauna of the Morrison Formation (Upper Jurassic), Rocky Mountain region, USA. New Mexico Museum of Natural History and Science 23:1-95.
- Division of Paleontology, American Museum of Natural History|