Ripley Formation | |
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Stratigraphic range: Upper Cretaceous | |
Rockground exposed in the Ripley Formation near Greenville, Alabama. | |
Type | Geological formation |
Unit of | Selma Group |
Sub-units | Cusseta Sand Member, McNairy Sand Member (Chronister dinosaur site) |
Underlies | Prairie Bluff Chalk Formation |
Overlies | Demopolis Chalk Formation |
Thickness | 40 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]
Prenoceratops, is a genus of herbivorous ceratopsian dinosaur from the Late Cretaceous Period. It was a relatively small dinosaur, reaching 1.3 m (4.3 ft) in length and 20 kg (44 lb) in body mass. Its fossils have been found in the upper Two Medicine Formation in the present-day U.S. state of Montana, in Campanian age rock layers that have been dated to 74.3 million years ago. Fossils were also found in the Oldman Formation in the modern day Canadian province of Alberta, dating to around 77 million years ago.
Glyptodontopelta is a monospecific genus of nodosaurid dinosaur from New Mexico that lived during the Late Cretaceous in what is now the Naashoibito member of the Ojo Alamo Formation. The type and only species, Glyptodontopelta mimus, is known from numerous specimens that consist of osteoderms, a dentary, supraorbital and bone fragments. It was named in 2000 by Tracy Ford. Edmontonia australis is a junior synonym of Glyptodontopelta.
The Bearpaw Formation, also called the Bearpaw Shale, is a geologic formation of Late Cretaceous (Campanian) age. It outcrops in the U.S. state of Montana, as well as the Canadian provinces of Alberta and Saskatchewan, and was named for the Bear Paw Mountains in Montana. It includes a wide range of marine fossils, as well as the remains of a few dinosaurs. It is known for its fossil ammonites, some of which are mined in Alberta to produce the organic gemstone ammolite.
The Lameta Formation, also known as the Infratrappean Beds, is a sedimentary geological formation found in Madhya Pradesh, Gujarat, Maharashtra, Telangana, and Andhra Pradesh, India, associated with the Deccan Traps. It is of the Maastrichtian age, and is notable for its dinosaur fossils.
The Pierre Shale is a geologic formation or series in the Upper Cretaceous which occurs east of the Rocky Mountains in the Great Plains, from Pembina Valley in Canada to New Mexico.
The Mooreville Chalk is a geological formation in North America, within the U.S. states of Alabama and Mississippi, which were part of the subcontinent of Appalachia. The strata date back to the early Santonian to the early Campanian stage of the Late Cretaceous. The chalk was formed by pelagic sediments deposited along the eastern edge of the Mississippi embayment. It is a unit of the Selma Group and consists of the upper Arcola Limestone Member and an unnamed lower member. Dinosaur, mosasaur, and primitive bird remains are among the fossils that have been recovered from the Mooreville Chalk Formation.
The Demopolis Chalk is a geological formation in North America, within the U.S. states of Alabama, Mississippi, and Tennessee. The chalk was formed by pelagic sediments deposited along the eastern edge of the Mississippi embayment during the middle Campanian age of the Late Cretaceous. It is a unit of the Selma Group and consists of the upper Bluffport Marl Member and a lower unnamed member. Dinosaur and mosasaur remains are among the fossils that have been recovered from the Demopolis Chalk.
The Selma Group is a geological formation in North America, within the U.S. states of Alabama, Mississippi, and Tennessee. The strata date from the Santonian to the Maastrichtian stages of the Late Cretaceous. The group is composed of, in ascending order, the Mooreville Chalk Formation, Demopolis Chalk Formation, Ripley Formation, and Prairie Bluff Chalk Formation. Dinosaur and mosasaur remains are among the fossils that have been recovered from the Selma Group.
The Eutaw Formation is a geological formation in North America, within the U.S. states of Alabama, Georgia, and Mississippi. The strata date from the late Coniacian to the early Santonian stage of the Late Cretaceous. It consists of the upper Tombigbee Sand Member and an unnamed lower member. Dinosaur, mosasaur, and pterosaur remains have been recovered from the Eutaw Formation.
Eothoracosaurus is an extinct monospecific genus of eusuchian crocodylomorphs found in Eastern United States which existed during the Late Cretaceous period. Eothoracosaurus is considered to belong to an informally named clade called the "thoracosaurs", named after the closely related Thoracosaurus. Thoracosaurs in general were traditionally thought to be related to the modern false gharial, largely because the nasal bones contact the premaxillae, but phylogenetic work starting in the 1990s instead supported affinities within gavialoid exclusive of such forms. Even more recent phylogenetic studies suggest that thoracosaurs might instead be non-crocodilian eusuchians.
The Marnes d’Auzas Formation is a geological Formation in southwestern France whose strata date back to the Late Maastrichtian. It is about 100 metres thick and consists primarily of marls with some interbeds of sandstones. It corresponds to sediments whose depositional environment evolved from the paralic domain at the base of the formation, towards a more continental domain in its upper part. The Marnes d’Auzas Formation was deposited in the west coast of the former Ibero-Armorican Island, which included much of France and Spain.
The Marshalltown Formation is a Mesozoic geologic formation in New Jersey and Delaware, US. Dinosaur remains diagnostic to the genus level are among the fossils that have been recovered from the formation.
The Severn Formation is a Mesozoic geologic formation in Maryland. Dinosaur remains diagnostic to the genus level are among the fossils that have been recovered from the formation.
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.
The Hornerstown Formation is a latest Cretaceous to early Paleocene-aged geologic formation in New Jersey. It preserves a variety of fossil remains, including those of dinosaurs, and contains direct evidence of the mass mortality that occurred at the Cretaceous-Paleogene boundary.
During most of the Late Cretaceous the eastern half of North America formed Appalachia, an island land mass separated from Laramidia to the west by the Western Interior Seaway. This seaway had split North America into two massive landmasses due to a multitude of factors such as tectonism and sea-level fluctuations for nearly 40 million years. The seaway eventually expanded, divided across the Dakotas, and by the end of the Cretaceous, it retreated towards the Gulf of Mexico and the Hudson Bay.
Paleontology in Missouri refers to paleontological research occurring within or conducted by people from the U.S. state of Missouri. The geologic column of Missouri spans all of geologic history from the Precambrian to present with the exception of the Permian, Triassic, and Jurassic. Brachiopods are probably the most common fossils in Missouri.
The Oulad Abdoun Basin is a phosphate sedimentary basin located in Morocco, near the city of Khouribga. It is the largest in Morocco, comprising 44% of Morocco's phosphate reserves, and at least 26.8 billion tons of phosphate. It is also known as an important site for vertebrate fossils, with deposits ranging from the Late Cretaceous (Cenomanian-Turonian) to the Eocene epoch (Ypresian), a period of about 25 million years.
The Chronister Dinosaur Site is a fossil site within the McNairy Sand Member of the Ripley Formation, Missouri. Dinosaur fossils are among the known remains from the Chronister Dinosaur Site, most of which are housed in Washington, D.C.'s Smithsonian Institution.