The Sanford Formation is a

Late Triassic The Late Triassic is the third and final epoch (geology), epoch of the Triassic geologic time scale, Period in the geologic time scale, spanning the time between annum, Ma and Ma (million years ago). It is preceded by the Middle Triassic Epoch ...

(

Norian The Norian is a division of the Triassic Period. It has the rank of an age ( geochronology) or stage (chronostratigraphy). It lasted from ~227 to million years ago. It was preceded by the Carnian and succeeded by the Rhaetian. Stratigraphic ...

)-age

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 ...

North Carolina North Carolina () is a state in the Southeastern region of the United States. The state is the 28th largest and 9th-most populous of the United States. It is bordered by Virginia to the north, the Atlantic Ocean to the east, Georgia a ...

. It is mainly found in the

Sanford sub-basin Sanford may refer to: People * Sanford (given name), including a list of people with the name * Sanford (surname), including a list of people with the name Places United States * Sanford, Alabama, a town in Covington County * Sanford, Colorad ...

of the

Deep River Basin Deep or The Deep may refer to: Places United States * Deep Creek (Appomattox River tributary), Virginia * Deep Creek (Great Salt Lake), Idaho and Utah * Deep Creek (Mahantango Creek tributary), Pennsylvania * Deep Creek (Mojave River tributary), ...

, the southernmost of the large

Mesozoic The Mesozoic Era ( ), also called the Age of Reptiles, the Age of Conifers, and colloquially as the Age of the Dinosaurs is the second-to-last era of Earth's geological history, lasting from about , comprising the Triassic, Jurassic and Creta ...

basins forming the Newark Supergroup. It is the highest unit of the

Chatham Group The Chatham Group is a Triassic-age geologic group in the eastern United States. It is one of the most fossiliferous sections of the Newark Supergroup, preserving much of the Late Triassic up until the Triassic-Jurassic mass extinction. The grou ...

, overlying the dark lake and swamp sediments of the

Cumnock Formation The Cumnock Formation is a Late Triassic-age geologic formation in North Carolina. It is found in the of the Sanford sub-basin of the Deep River Basin, the southernmost of the large Mesozoic basins forming the Newark Supergroup. It is the middle ...

. The Sanford Formation is composed primarily of coarse red sediments such as conglomerates,

sandstone Sandstone is a clastic sedimentary rock composed mainly of sand-sized (0.0625 to 2 mm) silicate grains. Sandstones comprise about 20–25% of all sedimentary rocks. Most sandstone is composed of quartz or feldspar (both silicates ...

s, and mudstones. The conglomerate layers contain pebbles of

schist Schist ( ) is a medium-grained metamorphic rock showing pronounced schistosity. This means that the rock is composed of mineral grains easily seen with a low-power hand lens, oriented in such a way that the rock is easily split into thin flakes ...

and

slate Slate is a fine-grained, foliated, homogeneous metamorphic rock derived from an original shale-type sedimentary rock composed of clay or volcanic ash through low-grade regional metamorphism. It is the finest grained foliated metamorphic ro ...

, with the occasional large boulders of

granite Granite () is a coarse-grained ( phaneritic) intrusive igneous rock composed mostly of quartz, alkali feldspar, and plagioclase. It forms from magma with a high content of silica and alkali metal oxides that slowly cools and solidifies und ...

. The Sanford Formation is likely equivalent to the Norian-age Passaic Formation of the

Newark Basin The Newark Basin is a sediment-filled rift basin located mainly in northern New Jersey but also stretching into south-eastern Pennsylvania and southern New York. It is part of the system of Eastern North America Rift Basins. Geology Approximat ...

in the northeastern United States. The lower part of the Sanford Formation has also been closely correlated with middle layers ("Lithofacies Association II") of the

Durham sub-basin Durham most commonly refers to: *Durham, England, a cathedral city and the county town of County Durham *County Durham, an English county * Durham County, North Carolina, a county in North Carolina, United States *Durham, North Carolina, a city in N ...

of the Deep River Basin. Though Sanford-equivalent strata are less clearly differentiable in the Durham sub-basin, they are also much more fossiliferous in that area.

References

Norian Stage Triassic geology of North Carolina {{Triassic-stub