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,Schuchert, C., and LeVene, C.M. 1940. O.C.Marsh, Pioneer in Paleontology. Yale University Press, New Haven. Shur,Shur, E. 1974. The Fossil Feud. Exposition Press, NY. 340p. Ostrom and McIntosh,Ostrom, J. H., and McIntosh, J.S. 1966. Marsh's Dinosaurs: The Collections from Como Bluff. Yale University Press, New Haven. and Jaffe.Jaffe, M. 2000. The Gilded Dinosaur. Crown Publ., New York. Most of the specimens were collected by men working for O.C. Marsh between 1877 and 1889, although some were collected by the Hubbel brothers for E.D. Cope between 1879 and 1880.McCarren, Mark J. The Scientific Contributions of Othniel Charles Marsh, pp 1, 8, 19-20, Peabody Museum of Natural History, Yale University, New Haven, Connecticut. . The American Museum of Natural History (AMNH) 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.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 More recently, Robert Bakker has done some collecting there with a variety of groups.
In addition to the major significance of dinosaur discoveries at Como Bluff, the site has also been the source of significant early mammal fossils. In early 1878, Marsh was ecstatic to find that one of his men had uncovered a fossil from a Jurassic mammal. Within a year, the historic Quarry 9 at Como was discovered, producing an astounding 250 specimens, which increased the knowledge of Jurassic mammals exponentially.McCarren, Mark J. The Scientific Contributions of Othniel Charles Marsh, pp 1, 7-8, 19-20, Peabody Museum of Natural History, Yale University, New Haven, Connecticut. .
Como Bluff historical quarries (pre-1900) Data source:.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| (h)= holotype
AMNH Quarries Excavated by the American Museum of Natural History
AMNH Quarry 1 Dinosauria Saurischia Sauropoda Diplodocus sp
AMNH Quarry 2 Dinosauria Saurischia Sauropoda Brontosaurus excelsus Camarasaurus sp,
AMNH localities unknown (some could be from Quarry 1 or 2) Reptilia Testudines Amphichelydia Glyptops plicatus Squamata ?Sauria indeterminant Lacertilia Paramacellodus sp. Choristodera Cteniogenys antiquus Crocodilia Mesosuchia Goniopholis sp.
Frederick Brown's Quarries
Brown's Quarry A Dinosauria Ornithischia Stegosauria Stegosaurus sp.
Brown's Quarry B Dinosauria Ornithischia Stegosauria Stegosaurus sp.
Brown's Quarry C Dinosauria Saurischia Theropoda Allosaurus fragilis
Brown's Quarry D Dinosauria Saurischia Theropoda Allosaurus fragilis
Brown's Quarry G Dinosauria Saurischia Sauropoda Camarasaurus sp.
Arthur Lakes Quarry 1A. (Big Canyon Quarry) Excavated by Arthur Lakes. Dinosauria Saurischia Theropoda Allosaurus sp. Sauropoda Camarasaurus sp. Ornithischia Ornithopoda Camptosaurus amplus (h) (now Allosaurus sp.)
E.D. Cope's Quarries Excavated by Edward Drinker Cope
Cope's Quarry 3 Dinosauria Saurischia Theropoda Allosaurus sp.
Cope's Quarry 4 Dinosauria Saurischia Theropoda Allosaurus sp. Ornithischia Stegosauria Stegosaurus sp.
Cope's Quarry 5 Reptilia Pterosauria Dermodactylus montanus Dinosauria Saurischia Sauropoda Apatosaurus sp.
Cope's localities unknown (could be from Quarry 1, 2) Reptilia Testudines Amphichelydia Dinochelys sp. Glyptops plicatus Crocodilia Mesosuchia Goniopholis sp. Dinosauria Ornithischia Ornithopoda ?Camptosaurus sp. Stegosauria Stegosaurus sp. Mammalia genus and species indeterminant
William Harlow Reed's Quarries Excavated by William Harlow Reed.
Reed's Quarry 1 Dinosauria Saurischia Theropoda Allosaurus atrox (h) (now Allosaurus fragilis) Sauropoda Camarasaurus grandis (h) Camarasaurus impar (h) (now Camarasaurus grandis) Camarasaurus robustus (h) (now Camarasaurus grandis) Pleurocoelus montanus (h) (now Camarasaurus grandis) Diplodocus sp. Mammalia genus and species indeterminant
Reed's Quarry 1 ½ Dinosauria Saurischia Theropoda Allosaurus fragilis Sauropoda genus and species indeterminant
Reed's Quarry 2 Dinosauria Saurischia Sauropoda Apatosaurus sp.
Reed's Quarry 3 Dinosauria Saurischia Theropoda Allosaurus lucaris (h) (now Allosaurus sp.) Sauropoda Camarasaurus grandis Ornithischia Ornithopoda Dryosaurus sp. Stegosauria Stegosaurus sp.
Reed's Quarry 4 Dinosauria Saurischia Theropoda Allosaurus fragilis Sauropoda Apatosaurus sp. Barosaurus sp. Camarasaurus sp. Ornithischia Stegosauria Stegosaurus sp.
Reed's Quarry 5 Reptilia Pterosauria Dermodactylus montanus (h) (now nomen dubium) Dinosauria Saurischia Sauropoda Diplodocus sp. Ornithischia Ornithopoda Dryosaurus altus (h)
Reed's Quarry 6 Reptilia Crocodylia Mesosuchia Goniopholis sp.
Reed's Quarry 7 (Three Trees Quarry) Dinosauria Ornithischia Ornithopoda Laosaurus consors (h) (now Othnielosaurus consors)
Reed's Quarry 8 Reptilia Testudines genus and species indeterminant Crocodilia Mesosuchia Goniopholis sp. Dinosauria Saurischia Theropoda Allosaurus sp. Coelurus fragilis Sauropoda Camarasaurus sp. Diplodocus sp. Ornithischia Stegosauria Stegosaurus sp.
Reed's Quarry 9 (Mammal Quarry) Osteichthyes Actinopterygii genus and species indeterminant Amiiformes Ophiopsis sp. Sarcopterygii Dipnoi Ceratodus guentheri Amphibia Anura Comobatrachus aenigmatis Discoglossoidea Enneabatrachus hechti Pelobatidae indeterminant Pipoidea? Eobatrachus agilis (h) Caudata genus and species indeterminant Comonecturoides marshi (h) Reptilia Testudines Amphichelydia Dinochelys whitei Glyptops ornatus Squamata ?Sauria indeterminant Lacertilia Dorsetisaurus sp. Paramacellodus sp. Rhynchocephalia Opisthias rarus (h) Theretairus antiquus (h) Choristodera Cteniogenys antiquus (h) Crocodylia Sphenosuchia Macelognathus vagans (h) Mesosuchia Goniopholis sp. Dinosauria Saurischia Theropoda Allosaurus fragilis Ceratosaurus nasicornis Coelurus fragilis Ornitholestes hermanni? Tyrannosauroidea Stokesosaurus clevelandi? Sauropoda Macronaria indeterminant Diplodocidae indeterminant Ornithischia Ornithopoda Othnielosaurus consors Dryosaurus sp. Camptosaurus sp. Stegosauria Stegosaurus sp. Pterosauria Rhamphorhynchoidea Laopteryx priscus (h) (now nomen dubium) Mammalia Docodonta Docodontidae Docodon affinis (h) Docodon crassus (h) Docodon striatus (h) Docodon superus (h) Docodon victor (h) Multituberculata Allodontidae Ctenacodon laticeps (h) Ctenacodon scindens (h) Ctenacodon serratus (h) Psalodon fortis (h) Psalodon potens (h) ?Psalodon marshi (h) Triconodonta Amphilestidae Aploconodon comoensis (h) Comodon gidleyi (h) Triconodontidae Priacodon ferox (h) Priacodon grandaevus (h) Priacodon lulli (h) Priacodon robustus (h) Trioracodon bisulcus (h) Symmetrodonta Amphidontidae Amphidon superstes (h) Tinodontidae Tinodon bellus (h) Eurylambda aequicrurius Dryolestida Dryolestidae Amblotherium gracilis (h) Dryolestes priscus Dryolestes obtusus (h) Dryolestes vorax (h) Laolestes eminens (h) Laolestes (Melanodon) goodrichi (h) Laolestes (Melanodon) oweni (h) Miccylotyrans minimus (h) Paurodontidae Araeodon intermissus (h) Archaeotrigon brevimaxillus (h) Archaeotrigon distagmus (h) Comotherium richi (h) Euthlastus cordiformis (h) Paurodon valens (h) Tathiodon agilis (h)
Reed's Quarry 10 Dinosauria Saurischia Sauropoda Brontosaurus excelsus (h)
Reed's Quarry 11 Dinosauria Saurischia Sauropoda Apatosaurus amplus (h) (now Brontosaurus excelsus) Ornithischia Stegosauria Stegosaurus duplex (h) (now Stegosaurus ungulatus) Mammalia genus and species indeterminant
Reed's Quarry 12 (Robbers' Roost Quarry) Reptilia Testudines genus and species indeterminant Crocodylia Mesosuchia Goniopholis sp. Dinosauria Saurischia Theropoda Allosaurus sp. Torvosaurus tanneri Coelurus sp. Fosterovenator churei Sauropoda Camarasaurus sp. Diplodocus sp. Ornithischia ornithopoda genus and species indeterminant Stegosauria Stegosaurus ungulatus (h)
Reed's Quarry 13 Reptilia Testudines Amphichelydia Glyptops plicatulus Crocodylia Mesosuchia Goniopholis sp. Dinosauria Saurischia Theropoda Coelurus agilis (h) (part of Coelurus fragilis holotype) Coelurus fragilis (h) Saurischia Sauropoda ?Brachiosaurus sp. Camarasaurus lentus (h) Diplodocus sp. Ornithischia Ornithopoda Camptonotus dispar (h) (now Camptosaurus dispar) Camptosaurus medius (h) Camptosaurus nanus (h) Camptosaurus browni (h) Dryosaurus sp. Stegosauria Diracodon laticeps (h) (now Stegosaurus sp.) Stegosaurus sulcatus (h) Stegosaurus stenops Stegosaurus ungulatus
Reed Quarry 14 Dinosauria Saurischia Theropoda Allosaurus ferox (h) (now Allosaurus fragilis)
See also List of fossil sites (with link directory)
References
External links
Como Bluffs fossil quarries
Dinosaur Fossil Cabin Museum