Demopolis Chalk Stratigraphic range: Upper Cretaceous | |
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Type | Geological formation |
Unit of | Selma Group |
Sub-units | Bluffport Marl Member |
Underlies | Ripley Formation |
Overlies | Mooreville Chalk Formation |
Lithology | |
Primary | Chalk |
Location | |
Region | Alabama, Mississippi, Tennessee |
Country | United States |
Type section | |
Named for | Demopolis, Alabama |
The Demopolis Chalk is a geological formation in North America, within the United States 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 stage of the Late Cretaceous.[1] It is a unit of the Selma Group and consists of the upper Bluffport Marl Member and a lower unnamed member.[2] Dinosaur and mosasaur remains are among the fossils that have been recovered from the Demopolis Chalk.[2][3]
Cartilaginous fish of the Demopolis Chalk Formation | ||||
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Genus | Species | Presence | Notes | Images |
C. appendiculata[2] |
An Otodontid |
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Scapanorhynchus sp.[2] |
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S. kaupi |
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S. pristodontus[2] |
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I. mira[2] |
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C. samhammeri |
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A. "kopingensis" |
Bony fish of the Demopolis Chalk Formation | ||||
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Genus | Species | Presence | Notes | Images |
E. petrosus[2] |
An enchodontid |
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P. gladius[2] |
A pachycormid | |||
X. vetus[4] |
Indeterminate hadrosaurid remains have been found in Tennessee .[3] Possible indeterminate tyrannosaurid remains have been found in Alabama.[3]
Dinosaurs of the Demopolis Chalk Formation | ||||
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Genus | Species | Presence | Notes | Images |
Geographically present in Alabama.[3] |
A tyrannosauroid |
Mosasaurs of the Demopolis Chalk | ||||
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Genus | Species | Presence | Notes | Images |
M. conodon[2] |
A mosasaurine |
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P. primaevus[5] |
A plioplatecarpine | |||
P. cf. rapax |
A mosasaurine |
Plesiosaurs of the Demopolis Chalk | ||||
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Genus | Species | Presence | Notes | Images |
Elasmosaurus sp.[2] |
An elasmosaurid |
Original source: https://en.wikipedia.org/wiki/Demopolis Chalk.
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