Stratigraphic range: Upper Jurassic (Kimmeridgian to Tithonian), 156.3–146.8 Ma
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The distinctive banding of the Morrison Formation, a group of rock layers that occur throughout Dinosaur National Monument and the source of fossils like those found at the Dinosaur Quarry
Type
Geologic formation
Underlies
Cedar Mountain Formation, Cloverly Formation, Lakota Formation, Burro Canyon Formation
Central North America: Arizona Colorado Idaho Kansas Montana Nebraska New Mexico North Dakota Oklahoma South Dakota Texas Utah Wyoming
Country
United States[1]
Extent
Type section
Named for
Morrison, Colorado
The Morrison Formation is a distinctive sequence of Upper Jurassic sedimentary rock found in the western United States which has been the most fertile source of dinosaur fossils in North America. It is composed of mudstone, sandstone, siltstone, and limestone and is light gray, greenish gray, or red. Most of the fossils occur in the green siltstone beds and lower sandstones, relics of the rivers and floodplains of the Jurassic period.
It is centered in Wyoming and Colorado, with outcrops in Montana, North Dakota, South Dakota, Nebraska, Kansas, the panhandles of Oklahoma and Texas, New Mexico, Arizona, Utah, and Idaho. Equivalent rocks under different names are found in Canada.[2] It covers an area of 1.5 million square kilometers (600,000 square miles), although only a tiny fraction is exposed and accessible to geologists and paleontologists. Over 75% is still buried under the prairie to the east, and much of its western paleogeographic extent was eroded during exhumation of the Rocky Mountains.
It was named after Morrison, Colorado, where some of the first fossils in the formation were discovered by Arthur Lakes in 1877. That same year, it became the center of the Bone Wars, a fossil-collecting rivalry between early paleontologists Othniel Charles Marsh and Edward Drinker Cope. In Colorado, New Mexico, and Utah, the Morrison Formation was a major source of uranium ore.
^"Morrison Formation" (PDF). CGKN. Retrieved 25 May 2013.[permanent dead link]
^Parrish, J.T.; Peterson, F.; Turner, C.E. (2004). "Jurassic "savannah"-plant taphonomy and climate of the Morrison Formation (Upper Jurassic, Western USA)" (PDF). Sedimentary Geology. 167 (3–4): 137–162. Bibcode:2004SedG..167..137P. doi:10.1016/j.sedgeo.2004.01.004.
and 29 Related for: Morrison Formation information
The MorrisonFormation is a distinctive sequence of Upper Jurassic sedimentary rock found in the western United States which has been the most fertile...
The MorrisonFormation is a distinctive sequence of Upper Jurassic sedimentary rock that is found in the western United States, which has been the most...
The MorrisonFormation is a distinctive sequence of Late Jurassic sedimentary rock that is found in the western United States, which has a wide assortment...
is the exact opposite of the Middle Jurassic. The Late Jurassic MorrisonFormation is found in several U.S. states, including Colorado, Utah, Wyoming...
recovered from named geologic formations (e.g. the MorrisonFormation or the Hell Creek Formation). When this is not the case, a city or landmark near...
years ago (mya) during the Kimmeridgian and Tithonian ages in the MorrisonFormation of what is now Utah and Wyoming. For decades, the animal was thought...
remains have come from North America's MorrisonFormation, with material also known from the Lourinhã Formation in Portugal. It was known for over half...
belong to the genus, making it one of the rarer sauropods of the MorrisonFormation. It is regarded as a high browser, possibly cropping or nipping vegetation...
middle to upper MorrisonFormation, between about 154 and 152 million years ago, during the late Kimmeridgian Age. The MorrisonFormation records an environment...
Sussanah (2019). "Two new stegosaur specimens from the Upper Jurassic MorrisonFormation of Montana, USA". Acta Palaeontologica Polonica. 64: 461–480. doi:10...
lizard-eaters") is a genus of large allosaurid dinosaur from the MorrisonFormation of Late Jurassic (latest Kimmeridgian age, about 151 million years...
years ago. Of the species that have been classified in the upper MorrisonFormation of the western US, only three are universally recognized: S. stenops...
related to the more familiar Diplodocus. Remains have been found in the MorrisonFormation from the Upper Jurassic Period of Utah and South Dakota. It is present...
skeleton discovered in Garden Park, Colorado, in rocks belonging to the MorrisonFormation. The type species is Ceratosaurus nasicornis. The Garden Park specimen...
Kimmeridgian to early Tithonian age, and are now known from fossils in the MorrisonFormation of modern-day Colorado, Oklahoma, New Mexico, Wyoming, and Utah in...
Shangshaximiao Formations in China, the Toqui Formation of Chile and Cañadón Calcáreo Formation and the MorrisonFormation, with the presence of dinosaurs with...
and in swampy plains during the Upper Jurassic. This became the MorrisonFormation, which is locally divided into three members (from oldest to youngest);...
Appalachian dinosaurs List of archosaurs of the Chinle Formation List of dinosaurs of the MorrisonFormation List of South American dinosaurs List of prehistoric...
together with Supersaurus remains, proved present in rocks of the MorrisonFormation. From 1972 onward, the site was excavated by Jensen and Kenneth Stadtman...
American sauropod fossil. Its fossil remains have been found in the MorrisonFormation, dating to the Late Jurassic epoch (Kimmeridgian to Tithonian stages)...
that estimated the body masses of mammals from the Late Jurassic MorrisonFormation by using the ratio of dentary length to body mass of modern marsupials...
geographic name plus either "Formation" or a descriptive name. Examples include the MorrisonFormation, named for the town of Morrison, Colorado, and the Kaibab...
ago, during the Late Jurassic-age. Its fossils are known from the MorrisonFormation of the south-western United States. The type and only species, Nanosaurus...
from his collectors at Quarry 13 near Como Bluff, Wyoming in the MorrisonFormation and C. amplus based on the holotype YPM 1879, a foot found by Arthur...
to this group. All members are known from the Late Jurassic-aged MorrisonFormation of the American West, dating to between 157 and 146.8 million years...
occurs between the underlying MorrisonFormation and overlying Naturita Formation (sometimes formerly called the Dakota Formation). It is composed of non-marine...