The Fort Payne Formation, or Fort Payne Chert, is a

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 ...

found in the southeastern region of the

United States The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country primarily located in North America. It consists of 50 states, a federal district, five major unincorporated territorie ...

.USGS.gov: Fort Payne Formation
/ref> It is a Mississippian Period

chert Chert () is a hard, fine-grained sedimentary rock composed of microcrystalline or cryptocrystalline quartz, the mineral form of silicon dioxide (SiO2). Chert is characteristically of biological origin, but may also occur inorganically as a prec ...

limestone Limestone ( calcium carbonate ) is a type of carbonate sedimentary rock which is the main source of the material lime. It is composed mostly of the minerals calcite and aragonite, which are different crystal forms of . Limestone forms whe ...

, that overlies the

Chattanooga Shale The Chattanooga Shale is a geologic formation in Alabama, Arkansas, Kentucky, Missouri and Tennessee. It preserves conodont fossils dating to the Devonian Period. It occurs mostly as a subsurface geologic formation composed of layers of shale. It ...

(or locally the Maury Formation), and underlies the

St. Louis Limestone The St. Louis Limestone is a large geologic formation covering a wide area of the midwest of the United States. It is named after an exposure at St. Louis, Missouri. It consists of sedimentary limestone with scattered chert beds, including the ...

(lower Tuscumbia Limestone in Alabama). To the north, it grades into the

siltstone Siltstone, also known as aleurolite, is a clastic sedimentary rock that is composed mostly of silt. It is a form of mudrock with a low clay mineral content, which can be distinguished from shale by its lack of fissility.Blatt ''et al.'' 1980, p ...

Borden 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 in ...

dating back to the

Carboniferous The Carboniferous ( ) is a geologic period and system of the Paleozoic that spans 60 million years from the end of the Devonian Period million years ago ( Mya), to the beginning of the Permian Period, million years ago. The name ''Carbonifero ...

period Period may refer to: Common uses * Era, a length or span of time * Full stop (or period), a punctuation mark Arts, entertainment, and media * Period (music), a concept in musical composition * Periodic sentence (or rhetorical period), a concept ...

Eugene Allen Smith Eugene Allen Smith (October 27, 1841 – September 7, 1927) was an American geologist. He was born in the (now former) town of Washington, Alabama, in 1841, the son of Samuel Parrish Smith and his wife Adelaide Julia Allen. After an education in ...

named the Fort Payne Formation for outcrops at

Fort Payne, Alabama Fort Payne is a city in and county seat of DeKalb County, in northeastern Alabama, United States. At the 2020 census, the population was 14,877. European-American settlers gradually developed the settlement around the former fort. It grew rapid ...

References

Geologic formations of Alabama Geologic formations of Tennessee Mississippian United States Carboniferous Alabama Carboniferous Kentucky Carboniferous geology of Tennessee Viséan Limestone formations of the United States Chert Carboniferous southern paleotemperate deposits Carboniferous southern paleotropical deposits {{US-geologic-formation-stub

See also

References