Keet Seel, Segi Canyon (UCMP V3308): Pliensbachian - Toarcian, Arizona
collected by R. H. Thomas & M. Littlesalt 1933
List of taxa
Where & when
Geology
Taphonomy & methods
Metadata & references
Taxonomic list
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Reptilia
- Coelophysidae
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Dinosauria indet.
(Owen 1842)
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1 individual | |||||||||
| (2 measurements) | ||||||||||
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= Saurischia indet.
Seeley 1888
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Camp and Vander Hoof 1934 | |||||||||
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= Segisaurus halli n. gen., n. sp.
Camp 1936
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Camp 1936 | |||||||||
| UCMP 32101 | ||||||||||
| see common names | ||||||||||
Geography
| Country: | United States | State/province: | Arizona | County: | Coconino |
| Coordinates: | 36.8° North, 110.5° West (view map) | ||||
| Paleocoordinates: | 23.9° North, 48.3° West | ||||
| Basis of coordinate: | stated in text | ||||
| Geographic resolution: | small collection |
Time
| Period: | Jurassic | Epoch: | Early/Lower Jurassic |
| *Period: | Early/Lower Jurassic | ||
| *International age/stage: | Early/Lower Hettangian - Late/Upper Toarcian | ||
| Key time interval: | Pliensbachian - Toarcian | ||
| Age range of interval: | 192.90000 - 174.70000 m.y. ago | ||
| * legacy (obsolete) database fields | |||
Stratigraphy
| Geological group: | Glen Canyon | Formation: | Navajo Sandstone | ||
| Stratigraphic resolution: | bed | ||||
| Stratigraphy comments: fossil found 500 feet above the base of the Navajo Sandstone, measured from the top of the underlying Wingate Sandstone, "and 100 feet below its upper level as exposed on the plateau of Skeleton (Zilh-nez') Mesa"
Navajo Sandstone forms uppermost part of Glen Canyon Group, and is Early Jurassic, but probably not older than Pliensbachian (Irmis 2005. A review of the vertebrate fauna of the Lower Jurassic Navajo Sandstone in Arizona. Mesa Southwest Museum Bulletin 11:55–71) | |||||
Lithology and environment
| Primary lithology: | dunes,"cross stratification",hematitic,red,yellow lithified calcareous sandstone |
| Secondary lithology: | red poorly lithified "shale" |
| Includes fossils? | Y |
| Lithology description: Navajo Sandstone is a homogenous, friable, fine-grained, aeolian sediment almost exclusively quartzose and with a calcareous cement. The constituent sand grains, though somewhat angular, are frosted and pitted and in most cases are covered with a thin film of iron oxide which imparts a brick red color to the rock. In some places [it] is poor or entirely lacking in iron oxide, resulting in a buff to nearly white aspect...the aeolian origin...is best shown by the type of cross-bedding of the sediments. At the point where the fossil occurred this cross-bedding is exposed in the long sweeping curves of the fore-set beds, sharply truncated above and set together like wedges at various angles." There is also a fine-grained, carbonaceous, supposedly freshwater limestone lens above the specimen. The shale appears as "soft lumps" that increase in frequency in the layers above the specimen and below the limestone. | |
| Environment: | dune |
Taphonomy
| Modes of preservation: | body |
| Degree of concentration: | dispersed |
| Size of fossils: | macrofossils |
| Spatial orientation: | life position |
| Preservation of anatomical detail: | good |
| Abundance in sediment: | rare |
| Articulated whole bodies: | all |
| Fragmentation: | occasional |
| Encrustation: | none |
| Temporal resolution: | snapshot |
| Spatial resolution: | autochthonous |
Collection methods and comments
| Collection methods: | selective quarrying,mechanical,field collection | ||
| Collection size: | 1 individuals | ||
| Reason for describing collection: | taxonomic analysis | ||
| Museum repositories: | UCMP | ||
| Collectors: | R. H. Thomas & M. Littlesalt | Collection dates: | 1933 |
| Collection method comments: Collected during the 1933 Rainbow Bridge-Monument Valley Expedition, led by A. Hall, VanderHoof & Camp. Discovered by student Robert H. Thomas and Navajo Max Littlesalt. | |||
Metadata
| Also known as: | Segisaurus type, UCMP V338, Camp | ||
| Database number: | 25306 | ||
| Authorizer: | M. Carrano | Enterer: | M. Carrano |
| Modifier: | M. Carrano | Research group: | vertebrate |
| Created: | 2002-09-07 21:00:26 | Last modified: | 2023-09-08 14:14:34 |
| Access level: | the public | Released: | 2002-09-07 21:00:26 |
| Creative Commons license: | CC BY | ||
Reference information
Primary reference:
| 54283. | Anonymous. 1933. Bones of a bird-like dinosaur. Science 78 (supp.)(2033):6-7 [M. Carrano/M. Carrano] |
Secondary references:
| 63594 | A. A. Baker, C. H. Dane, and J. B. Reeside. 1936. Correlation of the Jurassic formations of parts of Utah, Arizona, New Mexico and Colorado. United States Department of the Interior Geological Survey Professional Paper 183:1-66 [M. Carrano/M. Carrano/M. Carrano] | |
| 7096 | C. L. Camp. 1936. A new type of bipedal dinosaur from the Navajo Sandstone of Arizona. University of California Publications in Geological Sciences 24(2):39-56 [M. Carrano/M. Carrano/M. Carrano] | |
| 55545 | C. L. Camp and V. L. Vander Hoof. 1934. Bipedal dinosaur from Jurassic of northern Arizona. Pan-American Geologist 62(1):70 [M. Carrano/M. Carrano] | |
| 16598 | ETE | M. T. Carrano, J. R. Hutchinson, and S. D. Sampson. 2005. New information on Segisaurus halli, a small theropod dinosaur from the Early Jurassic of Arizona. Journal of Vertebrate Paleontology 25(4):835-849 [M. Carrano/K. Maguire/M. Carrano] |
| 12617 | ETE | P. M. Galton. 1971. The prosauropod dinosaur Ammosaurus, the crocodile Protosuchus, and their bearing on the age of the Navajo Sandstone of northeastern Arizona. Journal of Paleontology 45(5):781-795 [M. Carrano/M. Carrano/M. Carrano] |
| 63054 | C. W. Gilmore. 1939. A review of recent progress in reptilian paleontology. Bulletin of the Geological Society of America 50:337-348 [M. Carrano/M. Carrano] | |
| 80483 | J. W. Harshbarger, C. A. Repenning, and J. H. Irwin. 1957. Stratigraphy of the uppermost Triassic and the Jurassic rocks of the Navajo country. United States Geological Survey Professional Paper 291:1-74 [T. Hegna/M. Pankowski/M. Carrano] | |
| 24406 | ETE | R. B. Irmis. 2005. A review of the vertebrate fauna of the Lower Jurassic Navajo Sandstone in Arizona. In R. D. McCord (ed.), Vertebrate Paleontolgy of Arizona. Mesa Southwest Museum Bulletin 11:55-71 [M. Carrano/M. Carrano] |
| 71257 | E. T. McKnight. 1940. Geology of area between Green and Colorado rivers, Grand and San Juan counties, Utah. United States Geological Survey Bulletin 908:v-147 [M. Carrano/M. Carrano] | |
| 84543 | J. S. Tweet and V. L. Santucci. 2018. An inventory of non-avian dinosaurs from National Park Service areas. In S. G. Lucas & R. M. Sullivan (ed.), Fossil Record 6. New Mexico Museum of Natural History and Science Bulletin 79:703-730 [M. Carrano/M. Carrano] |