Sundance Formation
The Sundance Formation is a western North American sequence of Middle Jurassic to Upper Jurassic age[1] marine shale, sandy shale, sandstone, and limestone deposited in the Sundance Sea.
Sundance Formation Stratigraphic range: Middle Jurassic, Late Jurassic | |
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Type | Geological formation |
Underlies | Morrison Formation |
Overlies | Gypsum Springs Formation |
Lithology | |
Primary | shale |
Other | limestone, sandstone |
Location | |
Region | Western North America |
Country |
Geology
The Sundance Formation underlies the western North American Morrison Formation, the most fertile source of dinosaur fossils in the Americas, and is separated by a disconformity from the underlying Middle Jurassic Gypsum Springs Formation.
Fossils
The Sundance Formation is known for fossils of an extinct species of marine cephalopod, the belemnite Pachyteuthis densus, as well as several extinct species of oyster, including Deltoideum, Liostrea, and Gryphaea nebrascensis.
Fossil dinosaur 'footprints' on an ancient ocean shoreline are preserved in the formation and protected at the Red Gulch Dinosaur Tracksite, located in the Bureau of Land Management Red Gulch/Alkali National Back Country Byway, near Shell in Big Horn County, Wyoming.[2]
Vertebrate paleofauna
Pterosaurs
Pterosaurs of the Sundance Formation | ||||
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Taxa | Presence | Description | Images | |
Ichnogenus:
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Invertebrate paleofauna
Belemnoids
Belemnoids of the Sundance Formation | ||||
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Taxa | Presence | Description | Images | |
Genus:
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References
- Jennings, Debra S.; Stephen T. Hasiotis (2006). "Taphonomic analysis of a dinosaur feeding site using Geographic Information Systems (GIS), Morrison Formation, Southern Bighorn Basin, Wyoming, USA". PALAIOS. SEPM Society for Sedimentary Geology. 21 (5): 480–492. doi:10.2110/palo.2005.P05-062R.
- BLM−Bureau of Land Management, Wyoming Office: "Red Gulch Dinosaur Tracksite" website, info, maps, photo gallery, accessed 8.21.2015
- Lockley, M.; Harris, J.D.; and Mitchell, L. 2008. "A global overview of pterosaur ichnology: tracksite distribution in space and time." Zitteliana. B28. p. 187-198. ISSN 1612-4138.