Stratum.black
Coon Creek Formation — Coon Creek Formation
Coon Creek Formation — James St. John, Wikimedia Commons, CC BY 2.0

Formation · Cretaceous

Coon Creek Formation

Late Cretaceous unit, Tennessee · Mississippi

The Coon Creek Formation of western Tennessee is a Late Cretaceous marine marl whose shells retain their original aragonite, so Turritella, Exogyra oysters, crabs and ammonites come out looking almost modern. It is educational rather than commercial: the Coon Creek Science Center runs digs but restricts sale. Aragonitic Cretaceous shells are fragile and crumble as they dry; consolidate them promptly.

CountryUnited States
RegionTennessee, Mississippi
AgeMaastrichtian, Late Cretaceous
Age range~72–68 Ma
GroupRipley Formation
Macrostrat rankFm· Macrostrat
Macrostrat age75–72.2 Ma· Macrostrat
Lithologysand, clay· Macrostrat
Environmentcoastal indet., deltaic indet.· Macrostrat
Macrostrat columns1 column(s) sampled from 1 unit(s)· Macrostrat
PBDB collections35 collections, 1282 occurrences· Paleobiology Database

Collecting and legality

The type site is the Coon Creek Science Center (Pink Palace Museum, Memphis), open to school groups and occasional public digs; finds usually stay with the museum. Other exposures in McNairy County are private farmland; ask first.

Lithology and setting

Glauconitic, micaceous sandy marl of a shallow Mississippi Embayment shelf; the original aragonite shell is preserved unaltered.

Commonly recorded taxa (PBDB)

Genera most often recorded from this unit in the Paleobiology Database (first 200 occurrences): Turritella (20), Paladmete (9), Euspira (8), Volutomorpha (7), Anchura (6), Graciliala (6), Creonella (5), Gyrodes (5), Morea (5), Pyropsis (5), Amuletum (4), Drilluta (4), Graphidula (4), Lupira (4), Pugnellus (Pugnellus) (4).

Source: Paleobiology Database

Age

Collecting rules

Typical taxa

Elsewhere

Cite this article

Stratum Study. "Coon Creek Formation" (Formation). Stratum Study pack 2026.09, as of 2026-09-19. https://stratum.black/study/formations/coon-creek-formation. Accessed 2026-09-20.

BibTeX · CSL-JSON

@misc{stratum-coon-creek-formation,
  title        = {Coon Creek Formation},
  author       = {{Stratum Study}},
  howpublished = {\url{https://stratum.black/study/formations/coon-creek-formation}},
  year         = {2026},
  note         = {Formation article, Stratum Study pack 2026.09, as of 2026-09-19; sources: stratum, macrostrat, pbdb, wikidata, commons. Accessed 2026-09-20.}
}

Citations carry the pack version and the article's as-of date so they resolve to the same text later. The facts themselves belong to the sources listed below; cite those for the science.