Morrison Formation - Colorado - Montana - New Mexico - Oklahoma - South Dakota - Utah - Wyoming - US

The Morrison Formation is occupying more than 1.5 million km2 of the western United States. Radiometric dating shows that the Morrison Formation is enterely Late Jurassic (Kowallis et al., 1997). The northern exposures of the the Morrison Formation contain coal, suggesting a much wetter and swampier environment than the southwestern outcrops witch contains many eolian sandstones indicating a hot, arid sand dessert (Carpenter et al., 1997).

Adjacent to these sandstones are thick deposits of mudstone, formed by the deposition of mud from floods. In the sand- and mudstones most of the dinosaurs of the Morisson Formation are found. Dinosaur fossils are not the only fossils that are known from the Morrison Formation, fishes, frogs, salamanders, lizards, crocodiles, pterosaurs, dinosaur eggs, and shrew- to ratsized mammals are known from mostly fragmentary remains.


Allosaurus fragilis - Colorado, Montana, New Mexico, Oklahoma, South Dakota, Utah, Wyoming - Carnosauria Allosauridae - Jurassic Late Kimmeridgian Tithonian


Amphicoelias altus - Colorado - Diplodocidae Diplodocinae - Jurassic Late Kimmeridgian Tithonian



Amphicoelias fragillimus - Colorado - Diplodocidae Diplodocinae - Jurassic Late Kimmeridgian Tithonian



Amphicoelias latus - Colorado - Camarasauridae Camarasaurinae - Jurassic Late Kimmeridgian Tithonian



Antrodemus valens - Colorado - Carnosauria Allosauridae - Jurassic Late Tithonian



Apatodon mirus - [Dinosauria indet.] Nomina Dubia - Kimmeridgian Tithonian



Apatosaurus ajax - Colorado - Diplodocidae Diplodocinae - Jurassic Late Kimmeridgian Tithonian



Apatosaurus excelsus - Colorado, Oklahoma, Wyoming - Diplodocidae Diplodocinae - Jurassic Late Kimmeridgian Tithonian



Apatosaurus grandis - Colorado, Montana, Wyoming - Camarasauridae Camarasaurinae - Jurassic Late Kimmeridgian Tithonian



Apatosaurus louisae - Utah - Diplodocidae Diplodocinae - Jurassic Late Kimmeridgian Tithonian



Apatosaurus minimus? - Wyoming - Cetiosauridae Incertae Sedis - Jurassic Late Kimmeridgian Tithonian



Apatosaurus montanus - Colorado - Diplodocidae Nomina Dubia - Jurassic Late Kimmeridgian Tithonian



Apatosaurus yahnahpin - Wyoming - Apatosaurinae Nomina Dubia - Jurassic Late



Atlantosaurus immanis - Colorado - Diplodocidae Diplodocinae - Jurassic Late Kimmeridgian Tithonian



Atlantosaurus laticollis - Colorado - Diplodocidae Diplodocinae - Jurassic Late



Atlantosaurus minimus - Wyoming - Cetiosauridae Incertae Sedis - Jurassic Late Kimmeridgian Tithonian



Atlantosaurus montanus - Colorado - Diplodocidae Nomina Dubia - Jurassic Late Kimmeridgian Tithonian



Barosaurus affinis - South Dakota ?, Utah ? - Diplodocidae Diplodocinae - Jurassic Late Tithonian



Barosaurus lentus - New Mexico, South Dakota, Utah - Diplodocidae Diplodocinae - Jurassic Late Kimmeridgian Tithonian (?Cretaceous Early ?Aptian Albian Cenomanian)



Beelemodon - Wyoming - Nomen Nudem - Jurassic Late Kimmeridgian Tithonian



Brachiosaurus altithorax - Colorado, Utah - Sauropoda Brachiosauridae - Jurassic Late Kimmeridgian Tithonian



Brachyrophus altarkansanus - Colorado - Iguanodontia Camptosauridae - Jurassic Late Kimmeridgian Tithonian



\\\\\\\"Brontoraptor\\\\\\\" - Wyoming - Megalosauridae Nomen Nudem - Jurassic Late Kimmeridgian Tithonian



Brontosaurus ajax - Colorado - Diplodocidae Diplodocinae - Jurassic Late Kimmeridgian Tithonian



Brontosaurus amplus - Colorado - Diplodocidae Diplodocinae - Jurassic Late Kimmeridgian Tithonian



Brontosaurus excelsus - Colorado, Oklahoma, Wyoming - Diplodocidae Diplodocinae - Jurassic Late Kimmeridgian Tithonian



Brontosaurus montanus - Colorado - Diplodocidae Nomina Dubia - Jurassic Late Kimmeridgian Tithonian



Camarasaurus annae - Utah - Camarasauridae Camarasaurinae - Jurassic Late Kimmeridgian Tithonian



Camarasaurus grandis - Colorado, Montana, Utah, Wyoming - Camarasauridae Camarasaurinae - Jurassic Late Kimmeridgian Tithonian



Camarasaurus lentus - Utah, Wyoming - Camarasauridae Camarasaurinae - Jurassic Late Kimmeridgian Tithonian



Camarasaurus lewisi - Colorado - Camarasauridae Camarasaurinae - Jurassic Late Kimmeridgian Tithonian



Camarasaurus supremus - Colorado, New Mexico, Wyoming - Camarasauridae Camarasaurinae - Jurassic Late Kimmeridgian Tithonian



Camptonotus amplus - Wyoming - Carnosauria Allosauridae - Jurassic Late Kimmeridgian Tithonian



Camptosaurus amplus - Wyoming - Carnosauria Allosauridae - Jurassic Late Kimmeridgian Tithonian



Camptosaurus aphanoecetes - Utah - Iguanodontia Camptosauridae - Jurassic Late



Camptosaurus browni - Utah - Iguanodontia Camptosauridae - Jurassic Late Kimmeridgian Tithonian



Camptosaurus dispar - Colorado, Oklahoma, Utah, Wyoming - Iguanodontia Camptosauridae - Jurassic Late Kimmeridgian Tithonian



Camptosaurus nanus - Wyoming - Iguanodontia Camptosauridae - Jurassic Late Kimmeridgian Tithonian



Cathetosaurus lewisi - Colorado - Camarasauridae Camarasaurinae - Jurassic Late



Ceratosaurus dentisulcatus - Utah - Theropoda Ceratosauria - Jurassic Late Kimmeridgian Tithonian



Ceratosaurus magnicornis - ? - Theropoda Ceratosauria - Jurassic Late Kimmeridgian Tithonian



Ceratosaurus nasicornis - Colorado - Theropoda Ceratosauria - Jurassic Late Kimmeridgian Tithonian



Ceratosaurus willisobrienorum - Colorado, Utah - Ceratosauria Nomina Dubia - Jurassic Late Kimmeridgian Tithonian



Coelurus agilis - Wyoming - Tetanurae Coelurosauria - Jurassic Late Kimmeridgian Tithonian



Coelurus fragils - Utah, Wyoming - Tetanurae Coelurosauria - Jurassic Late Kimmeridgian Tithonian



Diplodocus carnegii - Utah, Wyoming - Diplodocidae Diplodocinae - Jurassic Late Kimmeridgian Tithonian



Diplodocus halli - New Mexico, Diplodocidae Diplodocinae - Jurassic Late Kimmeridgian Tithonian



Diplodocus hallorum - New Mexico, Diplodocidae Diplodocinae - Jurassic Late Kimmeridgian Tithonian



Diplodocus hayi - Utah - Diplodocidae Diplodocinae - Jurassic Late Kimmeridgian Tithonian



Diplodocus lacustris - Colorado - Diplodocidae Diplodocinae - Jurassic Late Kimmeridgian Tithonian



Diplodocus longus - Colorado, Utah - Diplodocidae Diplodocinae - Jurassic Late Kimmeridgian Tithonian



Drinker nisti - Wyoming - Ornithopoda Hypsilophodontidae - Jurassic Late Kimmeridgian Tithonian



Dryosaurus altus - Colorado, Utah, Wyoming - Ornithopoda Dryosauridae - Jurassic Late Kimmeridgian Tithonian



Dystrophaeus viaemalae - Utah - Diplodocidae Diplodocinae - Jurassic Late Kimmeridgian Tithonian



Dystylosaurus edwini - Colorado - Sauropoda Brachiosauridae - Jurassic Late Kimmeridgian Tithonian



Edmarka rex - Wyoming - Tetanurae Torvosauridae - Jurassic Late Kimmeridgian



Elaphrosaurus sp (1) - ? - Theropoda Incertae Sedis Nomina Dubia - Jurassic Late Kimmeridgian Tithonian



Eobrontosaurus - Wyoming - Diplodocidae Apatosaurinae - Jurassic Late



Fruitadens haagarorum - Ornithopoda Heterodontosauridae - Jurassic Late Tithonian



Gargoyleosaurus parkpini - Wyoming - Ankylosauria Ankylosauridae - Jurassic Late



Haplocanthosaurus delfsi - Colorado - Cetiosauridae Cetiosaurinae - Jurassic Late Kimmeridgian Tithonian



Haplocanthosaurus priscus - Colorado, Wyoming - Cetiosauridae Cetiosaurinae - Jurassic Late Kimmeridgian Tithonian



Haplocanthosaurus utterbacki - Cetiosauridae Cetiosaurinae - Jurassic Late Kimmeridgian Tithonian



Hesperosaurus mjosi - Wyoming - Stegosauria Stegosauridae - Jurassic Late Kimmeridgian Tithonian


Hypsirhophus discurus (1) - Colorado - Carnosauria Allosauridae - Jurassic Late Kimmeridgian Tithonian


Hypsirhophus discurus (2) - Colorado - Stegosauridae Nomina Dubia - Jurassic Late Kimmeridgian Tithonian


Hypsirhophus seeleyanus - ? - Stegosauria Stegosauridae - Jurassic Late Kimmeridgian Tithonian


Kaatedocus siberi - Diplodocidae Diplodocinae - Jurassic Late Kimmeridgian


Koparion douglassi - ? - Maniraptora ?Troodontidae - Jurassic Late


Labrosaurus ferox - Colorado - Carnosauria Allosauridae - Jurassic Late Kimmeridgian



Labrosaurus sulcatus - Colorado - Incertae Sedis \\\\\\\"Carnosaurs\\\\\\\" Nomina Dubia - Jurassic Late Kimmeridgian Tithonian



Laelaps trihedrodon - Colorado - Carnosauria Allosauridae - Jurassic Late Tithonian



Laosaurus celer - Wyoming - Dryosauridae Nomina Dubia - Jurassic Late Kimmeridgian Tithonian



Laosaurus consors - ? - Ornithopoda Hypsilophodontidae - Jurassic Late



Laosaurus gracilis - ? - Ornithopoda Hypsilophodontidae - Jurassic Late



Marshosaurus bicentesimus - Utah - Theropoda Incertae Sedis \\\\\\\"Carnosaurs\\\\\\\" - Jurassic Late Kimmeridgian Tithonian



Morosaurus agilis - Colorado - Cetiosauridae Cetiosaurinae - Jurassic Late Kimmeridgian Tithonian



Morosaurus lentus - Utah, Wyoming - Camarasauridae Camarasaurinae -Jurassic Late Kimmeridgian Tithonian



Mymoorapelta maysi - Colorado - Ankylosauria Polacanthidae - Jurassic Late Kimmeridgian



Nanosaurus agilis - Colorado, Wyoming - Dryosauridae Nomina Dubia - Jurassic Late Kimmeridgian Tithonian



Nanosaurus rex - Colorado - Ornithopoda Hypsilophodontidae - Jurassic Late Kimmeridgian Tithonian



Ornitholestes hermanni - Utah, Wyoming - Tetanurae Coelurosauria - Jurassic Late Kimmeridgian Tithonian



Othnielia rex - Colorado, Utah, Wyoming - Ornithopoda Hypsilophodontidae - Jurassic Late Kimmeridgian Tithonian



Othnielosaurus consors - Utah, Wyoming - Ornithopoda Hypsilophodontidae - Jurassic Late



Poekilopleuron valens - Colorado - Carnosauria Allosauridae - Jurassic Late Tithonian



Saurophaganax maximus - Colorado - Carnosauria Allosauridae - Jurassic Late Kimmeridgian Tithonian



Saurophagus maximus ? - Oklahoma - Carnosauria Allosauridae - Jurassic Late



Seismosaurus halli - New Mexico - Sauropoda Diplodocidae - Jurassic Late Kimmeridgian Tithonian



Stegosaurus affinis - Utah - Stegosauridae Nomina Dubia - Jurassic Late Kimmeridgian Tithonian



Stegosaurus armatus - Colorado, Utah, Wyoming - Stegosauria Stegosauridae - Jurassic Late Kimmeridgian Tithonian



Stegosaurus longispinus - ?Utah, Wyoming - Stegosauria Stegosauridae - Jurassic Late Kimmeridgian Tithonian



Stegosaurus stenops - Colorado, Wyoming, Utah - Stegosauria Stegosauridae - Jurassic Late Kimmeridgian Tithonian



Stegosaurus sulcatus - Wyoming - Stegosauria Stegosauridae - Jurassic Late Kimmeridgian Tithonian



Stegosaurus ungulatus - Utah, Wyoming - Stegosauria Stegosauridae - Jurassic Late Kimmeridgian Tithonian



Stokesosaurus clevelandi - Colorado, Utah - Tetanurae ?Carnosauria - Jurassic Late Kimmeridgian Tithonian



Supersaurus vivianae - Colorado - Diplodocidae Diplodocinae - Jurassic Late Kimmeridgian Tithonian



Suuwassea emilieae - Montana - Diplodocidae [Flagellicaudata] - Jurassic Late ?Tithonian



Tanycolagreus topwilsoni - Wyoming - Tetanurae Coelurosauria - Jurassic Late Kimmeridgian Tithonian



Tichosteus aequifacies - Colorado - Iguanodontia Nomina Dubia - Jurassic Late Kimmeridgian Tithonian



Tichosteus lucasanus - Colorado - Iguanodontia Nomina Dubia - Jurassic Late Kimmeridgian Tithonian



Titanosaurus montanus - Colorado - Diplodocidae Nomina Dubia - Jurassic Late Kimmeridgian Tithonian



Torvosaurus tanneri - Colorado - Tetanurae ?Carnosauria - Jurassic Late Kimmeridgian Tithonian



Ultrasauros macintoshi - Colorado - Diplodocidae Diplodocinae - Jurassic Late Kimmeridgian Tithonian



Uteodon aphanoecetes - Utah - Iguanodontia [Styracosterna] -Jurassic Late Tithonian



Wyomingraptor - Wyoming - Allosauridae Nomen Nudem - Jurassic Late Kimmeridgian



Dinosaur eggshell - Colorado - Dinosauria - Jurassic Late Kimmeridgian Tithonian



Ornithopod footprints - Colorado - Ornithopoda - Jurassic Late Kimmeridgian Tithonian



Sauropod footprints - Colorado - Sauropoda - Jurassic Late Kimmeridgian Tithonian



Theropod footprints - Colorado - Theropoda - Jurassic Late Kimmeridgian Tithonian



Apatosaurus sp. - Colorado - Diplodocidae Diplodocinae - Jurassic Late Kimmeridgian Tithonian



Diplodocus sp. - Colorado - Diplodocidae Diplodocinae - Jurassic Late Kimmeridgian Tithonian



Elaphrosaurus sp. - Colorado - Ornithomimosauria Incertae Sedis - Jurassic Late Kimmeridgian Tithonian



Ornithischia indet. - Colorado - Ornithischia - Jurassic Late Kimmeridgian Tithonian



Ornithomimosaur indet. -Colorado - Ornithomimosauria Incertae Sedis - Jurassic Late Kimmeridgian Tithonian



Stegosaurus sp. - Colorado - Stegosauria Stegosauridae - Jurassic Late Kimmeridgian Tithonian



Undescribed allosaurid (Jensen, 1985] - Colorado - Theropoda Allosauridae - Jurassic Late Kimmeridgian Tithonian



Undescribed diplodocid (Jensen, 1985) - Colorado - Diplodocidae Diplodocinae - Jurassic Late Kimmeridgian Tithonian



Undescribed iguanodontid (Armstrong pers. comm.) - Colorado - Ornithopoda Iguanodontia - Jurassic Late Kimmeridgian Tithonian



Camarasaurus sp. - Montana - Sauropoda Camarasauridae - Jurassic Late Kimmeridgian Tithonian



Diplodocus sp. - Montana - Diplodocidae Diplodocinae - Jurassic Late Kimmeridgian Tithonian



Ornithischia indet. - Montana - Ornithischia - Jurassic Late Kimmeridgian Tithonian



Sauropoda indet. - Montana - Sauropoda - Jurassic Late Kimmeridgian Tithonian



Stegosaurid indet. - Montana - Stegosauria - Jurassic Late Kimmeridgian Tithonian



Camarasaurus cf. supremus - New Mexico - Sauropoda Camarasauridae - Jurassic Late Kimmeridgian Tithonian



Ornithopod footprints - Oklahoma - Ornithopoda - Jurassic Late Kimmeridgian Tithonian



Sauropod footprints - Oklahoma - Sauropoda - Jurassic Late Kimmeridgian Tithonian



Ceratosaurus sp. - Oklahoma - Theropoda Ceratosauria - Jurassic Late Kimmeridgian Tithonian



Stegosaurus sp. - Oklahoma - Stegosauria Stegosauridae - Jurassic Late Kimmeridgian Tithonian



Theropod footprints - South Dakota - Theropoda - Jurassic Late Kimmeridgian Tithonian



?Diplodocid indet. - Utah - Sauropoda Diplodocidae - Jurassic Late Kimmeridgian Tithonian



?Haplocanthosaurus sp. - Utah - Sauropoda Cetiosauridae - Jurassic Late Kimmeridgian Tithonian



Camptosaurus sp. - Utah - Sauropoda Camptosauridae - Jurassic Late Kimmeridgian Tithonian



Dinosaur eggshell - Utah - Dinosauria - Jurassic Late Kimmeridgian Tithonian



Sauropoda indet. - Utah - Sauropoda - Jurassic Late Kimmeridgian Tithonian



Stegosaurus sp. - Utah - Stegosauria Stegosauridae - Jurassic Late Kimmeridgian Tithonian



Theropoda indet - Utah - Theropoda - Jurassic Late Kimmeridgian Tithonian



BYU 2028: Fragmentary skull and dentary. Note: Dentary shows similarities to Labrosaurus ferox. - Utah Upper Brushy Basin Member - Carnosauria Allosauridae - Jurassic Late Tithonian



Camarasaurus sp. - Wyoming - Sauropoda Camarasauridae - Jurassic Late Kimmeridgian Tithonian



Diplodocus sp. - Wyoming - Sauropoda Diplodocidae - Jurassic Late Kimmeridgian Tithonian



Stegosaurus sp. - Wyoming - Stegosauria Stegosauridae - Jurassic Late Kimmeridgian Tithonian