This article needs additional citations for verification .(October 2017) |
Prairie Bluff Chalk | |
---|---|
Stratigraphic range: Cretaceous | |
Type | Formation |
Unit of | Selma Group [1] |
Lithology | |
Primary | Chalk |
Location | |
Region | Alabama and Mississippi [1] |
Country | USA |
The Prairie Bluff Chalk is a geologic formation in Alabama and Mississippi. It preserves fossils dating back to the Cretaceous period. [2] [3]
The chalk was formed by marine sediments deposited along the eastern edge of the Mississippi embayment during the Maastrichtian stage of the Late Cretaceous. It is a unit of the Selma Group and marks the end of the Cretaceous in Alabama. Evidence has been found within the formation at Braggs, Moscow, and Millers Ferry in Alabama indicating an instantaneous to brief erosional event, most likely a tsunami, at the Cretaceous–Paleogene boundary (K–T boundary). It is hypothesized that this event, along with faulting and liquification of the Prairie Bluff Chalk, is related to the meteorite impact at the Chicxulub crater site, directly south, across the Gulf of Mexico, from the formation. [4]
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 stage 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 Shakopee Formation is a geologic formation in Illinois, Indiana, Wisconsin, and Minnesota. It preserves fossils dating back to the Ordovician period. It is named after the town of Shakopee, Minnesota, where the formation can be seen in bluffs along the Minnesota River
The Peedee Formation is a geologic formation in North and South Carolina. A marine deposit, named for exposures along the Great Peedee River, it preserves belemnites and foraminifera fossils dating from the Late Cretaceous. The formation is notable for its occurrence of Belemnitella americana, known as the Pee Dee Belemnite (PDB), a long-standing standard in stable carbon isotope research.
The Owl Creek Formation is a geologic formation ranging from Tennessee to Mississippi. It preserves fossils dating back to the Cretaceous period. Ornithomimids and ceratopsid remains are known from the formation. The ceratopsid tooth could represent a chasmosaurine.
The Tallahatta Formation is a geologic formation found on the surface in Alabama, Florida, Georgia, and Mississippi. It is also located in the subsurface of Kentucky. The Tallahatta formation is part of the Claiborne Group and contains four members: the Basic City Shale in Mississippi, the Holy Springs Sand Member in Mississippi, the Meridian Sand Member in Alabama and Mississippi, and the Neshoba Sand Member in Mississippi. It preserves fossils dating back to the Paleogene period, specifically the Eocene.
The Hatchetigbee Bluff Formation is a geologic formation in Alabama, Georgia, Louisiana and Mississippi. The youngest unit of the Wilcox Group preserves fossils dating back to the Ypresian stage of the Eocene period, or Wasatchian in the NALMA classification. The formation is named for Hatchetigbee Bluff on the Tombigbee River, Washington County, Alabama.
The Red Bluff Formation is a geologic formation in Alabama. It preserves fossils dating back to the Paleogene period.
The Tuscaloosa Formation is a geologic formation in Alabama. It preserves fossils dating back to the Cretaceous period.
Yazoo Clay is a clay geologic formation in Alabama, Louisiana, and Mississippi. It was named after a bluff along the Yazoo River at Yazoo City, Mississippi It contains is a type of clay known as montmorillonite, making it a poor foundation material due to the fact that moisture causes extreme changes in volume. Sand, pyrite, and marl have all been noted in the formation. It preserves fossils from the Eocene, including the prehistoric cetacean Basilosaurus.
The Chiwapa Formation is a geologic formation in Mississippi. It preserves fossils dating back to the Cretaceous period.
The Winona Formation is a sand geologic formation in Mississippi. It preserves fossils dating back to the Paleogene period.
The Saratoga Chalk is a geologic formation in Arkansas. It preserves fossils dating back to the Cretaceous period, specifically ammonites.
The White Bluff Formation is a marl, sand, and clay geologic formation in Arkansas that is part of the Jackson Group. It preserves fossils dating back to the Paleogene period, specifically the Eocene.
The Windrow Formation is a geologic formation in Minnesota named after Windrow Bluff on Fort McCoy, Monroe County, Wisconsin. It preserves fossils dating back to the Cretaceous period.
The Pecan Gap Chalk is a geologic formation in Texas. It preserves fossils dating back to the Cretaceous period.
The Ector Chalk is a geologic formation in Texas. It preserves fossils dating back to the Cretaceous period.
The Gober Chalk is a geologic formation in Texas. It preserves fossils dating back to the Cretaceous period.
The Schrader Bluff Formation is a geologic formation in Alaska. It preserves fossils dating back to the Cretaceous period,