Ripley Formation

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Ripley Formation
Stratigraphic range: Upper Cretaceous
Maastrichtian Ripley Formation rockground near Greenville, Alabama.JPG
Rockground exposed in the Ripley Formation near Greenville, Alabama.
Type Geological formation
Unit of Selma Group
Sub-unitsCusseta Sand Member, McNairy Sand Member (Chronister dinosaur site)
Underlies Prairie Bluff Chalk Formation
Overlies Demopolis Chalk Formation
Thickness40 m (130 ft) to 175 m (574 ft)
Lithology
Primary Glauconitic sandstone
Other Micaceous chalk
Location
Region Alabama, Georgia, Mississippi, Missouri, Tennessee
Country United States
Type section
Named for Ripley, Mississippi

The Ripley Formation is a geological formation in North America found in the U.S. states of Alabama, Georgia, Mississippi, Missouri, [1] and Tennessee. The lithology is consistent throughout the layer. It consists mainly of glauconitic sandstone. It was formed by sediments deposited during the Maastrichtian stage of the Late Cretaceous. It is a unit of the Selma Group and consists of the Cusseta Sand Member, McNairy Sand Member and an unnamed lower member. [2] It has not been extensively studied by vertebrate paleontologists, due to a lack of accessible exposures. However, fossils have been unearthed including crocodile, hadrosaur, nodosaur, tyrannosaur, ornithomimid, dromaeosaur, and mosasaur remains have been recovered from the Ripley Formation. [2]

Contents

Paleofauna

See also

Related Research Articles

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<i>Hypsibema missouriensis</i> Extinct species of dinosaur

Hypsibema missouriensis is a species of plant-eating dinosaur in the genus Hypsibema, and the state dinosaur of the U.S. state Missouri. One of the few official state dinosaurs, bones of the species were discovered in 1942, at what later became known as the Chronister Dinosaur Site near Glen Allen, Missouri. The remains of Hypsibema missouriensis at the site, which marked the first known discovery of dinosaur remains in Missouri, are the only ones to have ever been found. Although first thought to be a sauropod, later study determined that it was a hadrosaur, or "duck-billed" dinosaur, whose snouts bear likeness to ducks' bills. Some of the species' bones found at the Chronister Dinosaur Site are housed in Washington, D.C.'s Smithsonian Institution.

<span class="mw-page-title-main">Appalachia (landmass)</span> Mesozoic land mass separated from Laramidia to the west by the Western Interior Seaway

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<span class="mw-page-title-main">Chronister dinosaur site</span> Fossil site in Missouri

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References

  1. "Hypsibema missouriensis". DinoData. 2011. Archived from the original on September 13, 2011. Retrieved January 12, 2011.
  2. 1 2 Kiernan, Caitlin R. (2002). "Stratigraphic distribution and habitat segregation of mosasaurs in the Upper Cretaceous of western and central Alabama, with an historical review of Alabama mosasaur discoveries". Journal of Vertebrate Paleontology. 22 (1): 91–103. doi:10.1671/0272-4634(2002)022[0091:SDAHSO]2.0.CO;2. S2CID   130280406.
  3. "Table 20.1," in Weishampel, et al. (2004). Page 443.
  4. 1 2 Parris, David. "CHRONISTER SITE INVESTIGATIONS: NEW INFORMATION ON THE CRETACEOUS OF MISSOURI" . Retrieved 6 October 2006.
  5. Bruns, Michael E. "NEW APPALACHIAN ARMORED DINOSAUR MATERIAL (NODOSAURIDAE, ANKYLOSAURIA) FROM THE MAASTRICHTIAN RIPLEY FORMATION OF ALABAMA". The Geological Society of America. Retrieved 1 April 2016.
  6. Powers, Marc (February 19, 2004). "A bone to pick for Missouri". Southeast Missourian. Southeast Missourian. Archived from the original on November 18, 2015. Retrieved January 12, 2011.
  7. 1 2 3 Fix, Michael F.; Darrough, Guy (2004). "Dinosauria and associated vertebrate fauna of the Late Cretaceous Chronister site of southeast Missouri". Abstracts with Programs. Geological Society of America. 36 (3): 14. Archived from the original on 2012-03-31. Retrieved 2016-08-28.
  8. Holloway, Brad (January 31, 2005). "Rock of ages – Museum reveals fossil find in Bollinger County". Southeast Missourian. Southeast Missourian. Retrieved January 14, 2011.
  9. "Missouri Dinosaur - Chronister Vertebrate Site - Bruce Sinchcomb". www.lakeneosho.org. Retrieved 2021-12-12.
  10. Brochu, Christopher A. (2004-09-10). "A new Late Cretaceous gavialoid crocodylian from eastern North America and the phylogenetic relationships of thoracosaurs". Journal of Vertebrate Paleontology. 24 (3): 610–633. doi:10.1671/0272-4634(2004)024[0610:anlcgc]2.0.co;2. ISSN   0272-4634. S2CID   131176447.
  11. Kenneth., Carpenter (1983). Thoracosaurus neocesariensis (De Kay, 1842) (Crocodylia: Crocodylidae) from the Late Cretaceous Ripley Formation of Mississippi. [s.n.] OCLC   895629547.