Yazoo Clay is a

clay Clay is a type of fine-grained natural soil material containing clay minerals (hydrous aluminium phyllosilicates, e.g. kaolinite, ). Most pure clay minerals are white or light-coloured, but natural clays show a variety of colours from impuriti ...

geologic formation A geological formation, or simply formation, is a body of rock having a consistent set of physical characteristics ( lithology) that distinguishes it from adjacent bodies of rock, and which occupies a particular position in the layers of rock exp ...

Alabama Alabama ( ) is a U.S. state, state in the Southeastern United States, Southeastern and Deep South, Deep Southern regions of the United States. It borders Tennessee to the north, Georgia (U.S. state), Georgia to the east, Florida and the Gu ...

Louisiana Louisiana ( ; ; ) is a state in the Deep South and South Central regions of the United States. It borders Texas to the west, Arkansas to the north, and Mississippi to the east. Of the 50 U.S. states, it ranks 31st in area and 25 ...

, and

Mississippi Mississippi ( ) is a U.S. state, state in the Southeastern United States, Southeastern and Deep South regions of the United States. It borders Tennessee to the north, Alabama to the east, the Gulf of Mexico to the south, Louisiana to the s ...

. It was named after a bluff along the Yazoo River at

Yazoo City, Mississippi Yazoo City is the county seat of Yazoo County, Mississippi, Yazoo County, Mississippi, United States. It was named after the Yazoo River, which, in turn was named by the French explorer Robert La Salle in 1682 as "Rivière des Yazous" in referen ...

. It contains is a type of clay known as

montmorillonite Montmorillonite is a very soft phyllosilicate group of minerals that form when they precipitate from water solution as microscopic crystals, known as clay. It is named after Montmorillon in France. Montmorillonite, a member of the smectite grou ...

, 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 A fossil (from Classical Latin , ) is any preserved remains, impression, or trace of any once-living thing from a past geological age. Examples include bones, shells, exoskeletons, stone imprints of animals or microbes, objects preserved ...

from the

Eocene The Eocene ( ) is a geological epoch (geology), epoch that lasted from about 56 to 33.9 million years ago (Ma). It is the second epoch of the Paleogene Period (geology), Period in the modern Cenozoic Era (geology), Era. The name ''Eocene'' comes ...

, including the prehistoric

cetaceans Cetacea (; , ) is an infraorder of aquatic mammals belonging to the order Artiodactyla that includes whales, dolphins and porpoises. Key characteristics are their fully aquatic lifestyle, streamlined body shape, often large size and exclusively c ...

Basilosaurus ''Basilosaurus'' (meaning "king lizard") is a genus of large, predatory, prehistoric archaeocete whale from the late Eocene, approximately 41.3 to 33.9 million years ago (mya). First described in 1834, it was the first archaeocete and prehisto ...

'' and ''

Zygorhiza ''Zygorhiza'' ("Yoke-Root") is an extinct genus of basilosaurid early whale known from the Late Eocene (Priabonian, 38–34 Ma) of Louisiana, Alabama, and Mississippi, United States, and the Bartonian (43–37 Ma on the New Zealand geologic tim ...

'', and the marine snake ''

Pterosphenus ''Pterosphenus'' is an extinct genus of marine snake of the Eocene period. Classification ''Pterosphenus'' belong to the Alethinophidia snakes, a clade which includes all snakes outside of Scolecophidia, blind and Leptotyphlopidae, thread sna ...

''. Sharks, rays, eels, and fish have also been found from the formation.https://www.mdeq.ms.gov/wp-content/uploads/2017/06/Circular_1.pdf

References

* * Geologic formations of Alabama Paleogene Louisiana Paleogene Mississippi Marl formations {{Alabama-geologic-formation-stub

See also

References