Mooreville Chalk | |
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Stratigraphic range: Upper Cretaceous | |
Type | Geological formation |
Unit of | Selma Group |
Sub-units | Arcola Limestone Member |
Underlies | Demopolis Chalk Formation |
Overlies | Eutaw Formation |
Lithology | |
Primary | Chalk |
Location | |
Region | Alabama, Mississippi |
Country | United States |
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. [1] 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. [2] Dinosaur, mosasaur, and primitive bird remains are among the fossils that have been recovered from the Mooreville Chalk Formation. [1] [2] [3]
Cartilaginous fish of the Mooreville Chalk Formation | ||||||
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Genus | Species | Location | Stratigraphic position | Abundance | Notes | Images |
C. appendiculata [3] | ||||||
C. mantelli [3] | ||||||
E. barberi [4] | ||||||
E. mirificus [4] | ||||||
I. williamsae [4] | ||||||
O. cuspidata | ||||||
P. hewletti [4] | ||||||
P. mammillaris [4] | ||||||
P. mortoni [3] | ||||||
P. polygyrus [4] | ||||||
P. affinis [4] | ||||||
P. laevis [3] | ||||||
S. serrata [3] | ||||||
S. rhaphiodon [4] | ||||||
S. texanus [3] | ||||||
S. falcatus [4] | ||||||
S. kaupi [3] | ||||||
Bony fish of the Mooreville Chalk Formation | ||||||
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Genus | Species | Location | Stratigraphic position | Abundance | Notes | Images |
A. dunklei [4] | An albuliform | |||||
B. crieleyi [4] | ||||||
C. nepaholica [4] | An aulopiform | |||||
An aulopiform | ||||||
E. saevus [4] | ||||||
Hoplopteryx sp. [4] | ||||||
I. ctenodon [4] | ||||||
M. hardi [4] | ||||||
P. caninus [4] | ||||||
P. gladius [3] | ||||||
S. leanus [4] | ||||||
S. apicalis [4] | An aulopiform | |||||
X. audax [4] | ||||||
Indeterminate hadrosaurid, nodosaurid, dinosaur egg, and ornithomimosaur fossils are known from Mooreville Chalk outcrops in Alabama. [1] The nodosaurid remains most likely belong to a new taxon. [5]
Color key
| Notes Uncertain or tentative taxa are in small text; |
Dinosaurs reported from the Mooreville Chalk Formation | ||||||
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Genus | Species | Location | Stratigraphic position | Material | Notes | Images |
A. antecessor | A. antecessor was originally described as Plegadornis antecessor, but the generic name Plegadornis was preoccupied, so the genus Angelinornis was erected to contain the species. It was later demonstrated that Angelinornis was a junior synonym of Ichthyornis , although the new combination I. antecessor was held to be valid for a while following the sinking of Angelinornis into Ichthyornis. Later the species would later be considered a junior synonym of the Ichthyornis type species, I. dispar. [1] | |||||
E. orientalis | A hadrosaurid known from a nearly complete skeleton and nearly complete skull. | |||||
"Vertebrae and limb elements." [7] | ||||||
I. antecessor | The species I. antecessor was made the type species of the genus Angelinornis in 1962. Later, I. antecessor and Angelinornis were shown to be junior synonyms of the Ichthyornis type species, I. dispar [1] | |||||
An ichthyornithine. | ||||||
A primitive species of hadrosaurid known from only a few skull fragments. [1] | ||||||
Saurornitholestes [5] | S. sp. | A dromaeosaurid. | ||||
P. antecessor | The name Plegadornis antecessor was applied to a fossil believed to represent a new bird species, but the generic name Plegadornis was preoccupied, so the genus Angelinornis was erected to contain the "new" species. It was later demonstrated that Angelinornis was a junior synonym of Ichthyornis , although the new combination I. antecessor was held to be valid for a while following the sinking of Angelinornis into Ichthtyornis. Later the species would later be considered a junior synonym of the Ichthyornis type species, I. dispar. [1] | |||||
Mosasaurs of the Mooreville Chalk Formation | ||||||
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Genus | Species | Location | Stratigraphic position | Abundance | Notes | Images |
C. liodontus [4] | ||||||
C. "moorevillensis" [3] | ||||||
Ectenosaurus | E. shannoni [8] | A plioplatecarpine | ||||
A halisaurine E. sternbergii was formerly classified as Halisaurus sternbergii [10] | ||||||
E. zangerli [11] | ||||||
G. alabamaensis [3] | ||||||
M. missouriensis [3] | ||||||
P. tympaniticus [3] | ||||||
P. rapax [4] | ||||||
S. russelli [3] | ||||||
T. proriger [4] | ||||||
Very rare elasmosaurs are present in this formation. [3]
Plesiosaurs of the Mooreville Chalk Formation | ||||||
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Genus | Species | Location | Stratigraphic position | Abundance | Notes | Images |
Trinacromerum sp. [3] | ||||||
Pterosaurs of the Mooreville Chalk Formation | ||||||
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Genus | Species | Location | Stratigraphic position | Abundance | Notes | Images |
Pteranodon sp. [3] | ||||||
Turtles of the Mooreville Chalk Formation | ||||||
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Genus | Species | Location | Stratigraphic position | Abundance | Notes | Images |
B. barberi [3] | A pelomedusid. | |||||
C. haliniches | A dermochelyid. | |||||
P. gigas [3] | A protostegid. | |||||
T. moorevillensis [3] | A toxochelyid. | |||||
Selmasaurus is an extinct genus of marine lizard belonging to the mosasaur family. It is classified as part of the Plioplatecarpinae subfamily alongside genera like Angolasaurus and Platecarpus. Two species are known, S. russelli and S. johnsoni; both are exclusively known from Santonian deposits in the United States.
The Mosasaurinae are a subfamily of mosasaurs, a diverse group of Late Cretaceous marine squamates. Members of the subfamily are informally and collectively known as "mosasaurines" and their fossils have been recovered from every continent except for South America.
Protostega is an extinct genus of sea turtle containing a single species, Protostega gigas. Its fossil remains have been found in the Smoky Hill Chalk formation of western Kansas, time-equivalent beds of the Mooreville Chalk Formation of Alabama and Campanian beds of the Rybushka Formation. Fossil specimens of this species were first collected in 1871, and named by Edward Drinker Cope in 1872. With a total length of 3.9 metres (13 ft), it is the second-largest sea turtle that ever lived, second only to the giant Archelon, and one of the three largest turtle of all time along Archelon and Gigantatypus.
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.
Halimornis was an enantiornithean bird. It lived during the Late Cretaceous about 80 mya and is known from fossils found in the Mooreville Chalk Formation in Greene County, Alabama. It is known from a single fossil individual, including preserved vertebrae, leg bones and part of the humerus.
Velafrons is a genus of lambeosaurine hadrosaurid dinosaur from the Late Cretaceous of Mexico. It is known from a mostly complete skull and partial skeleton of a juvenile individual, with a bony crest on the forehead. Its fossils were found in the late Campanian-age Cerro del Pueblo Formation, near Rincon Colorado, Coahuila, Mexico. The type specimen is CPC-59, and the type species is V. coahuilensis.
Paleontology or palaeontology is the study of prehistoric life forms on Earth through the examination of plant and animal fossils. This includes the study of body fossils, tracks (ichnites), burrows, cast-off parts, fossilised feces (coprolites), palynomorphs and chemical residues. Because humans have encountered fossils for millennia, paleontology has a long history both before and after becoming formalized as a science. This article records significant discoveries and events related to paleontology that occurred or were published in the year 2008.
Ctenochelys is an extinct genus of marine turtle, which existed during the Cretaceous period, and lived in the shallow waters of the Western Interior Seaway. Its fossils have been found in the Ripley Formation and Mooreville Chalk of central Alabama, United States. It was first named by C. H. Sternberg in 1904, and contains two species, C. stenoporus and C. acris.
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.
The Ripley Formation is a geological formation in North America found in the U.S. states of Alabama, Georgia, Mississippi, Missouri, 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. 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.
During the time of the deposition of the Niobrara Chalk, much life inhabited the seas of the Western Interior Seaway. By this time in the Late Cretaceous many new lifeforms appeared such as mosasaurs, which were to be some of the last of the aquatic lifeforms to evolve before the end of the Mesozoic. Life of the Niobrara Chalk is comparable to that of the Dakota Formation, although the Dakota Formation, which was deposited during the Cenomanian, predates the chalk by about 10 million years.
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. This left the island masses joined in the continent of North America as the Rocky Mountains rose. From the Cenomanian to the end of the Campanian ages of the Late Cretaceous, Appalachia was separated from the rest of North America. As the Western Interior Seaway retreated in the Maastrichtian, Laramidia and Appalachia eventually connected. Because of this, its fauna was isolated, and developed very differently from the tyrannosaur, ceratopsian, hadrosaurid, pachycephalosaur and ankylosaurid dominated fauna of the western part of North America, known as "Laramidia".
Magnapaulia is a genus of herbivorous lambeosaurine hadrosaurid dinosaurs known from the Latest Cretaceous Baja California, of northwestern Mexico. It contains a single species, Magnapaulia laticaudus. Magnapaulia was first described in 1981 as a possible species of Lambeosaurus by William J. Morris, and was given its own genus in 2012 by Prieto-Márquez and colleagues.
Paleontology in Alabama refers to paleontological research occurring within or conducted by people from the U.S. state of Alabama. Pennsylvanian plant fossils are common, especially around coal mines. During the early Paleozoic, Alabama was at least partially covered by a sea that would end up being home to creatures including brachiopods, bryozoans, corals, and graptolites. During the Devonian the local seas deepened and local wildlife became scarce due to their decreasing oxygen levels.
Augustynolophus is an extinct genus of herbivorous saurolophine hadrosaur dinosaur which was discovered in the Moreno Formation in California, dating to the late Maastrichtian age, making it one of the last dinosaurs known from the fossil record before the Cretaceous–Paleogene extinction event.
Eotrachodon orientalis is a species of hadrosaurid that was described in 2016. The holotype was found in the Mooreville Chalk Formation in Alabama in 2007 and includes a well-preserved skull and partial skeleton, making it a rare find among dinosaurs of Appalachia. Another primitive hadrosaur, Lophorhothon, is also known from the same formation, although Eotrachodon lived a few million years prior. A phylogenetic study has found Eotrachodon to be the sister taxon to the hadrosaurid subfamilies Lambeosaurinae and Saurolophinae. This, along with the other Appalachian hadrosaur Hadrosaurus and possibly Lophorhothon, Claosaurus and both species of Hypsibema, suggests that Appalachia was the ancestral area of Hadrosauridae.
Calcarichelys is an extinct genus of protostegid turtle from the Late Cretaceous of the Selma Formation in Alabama, and possibly from Angola. It contains only one species, C. gemma.