Catharpin Creek Formation

Last updated
Bull Run Formation
Stratigraphic range: Late Triassic,
late Norian to Rhaetian
Type Geological formation
Unit of Chatham Group
Sub-unitsGoose Creek Member
Underlies Mount Zion Church Basalt
Overlies Bull Run Formation
Lithology
Primary sandstone, conglomerate
Other shale, siltstone
Location
Region Maryland, Virginia
CountryFlag of the United States.svg  United States
Extent Culpeper Basin
Type section
Named forCatharpin Creek, Virginia
Named byLee & Froelich, 1989

The Catharpin Creek Formation is a Late Triassic (late Norian to Rhaetian) geologic formation in Maryland and Virginia. It is found along the western edge of the Culpeper Basin, one of the largest sedimentary basins in the Newark Supergroup. Compared to the underlying Bull Run Formation, the Catharpin Creek Formation is dominated by much coarser sedimentary rocks such as sandstone and conglomerate. [1] The base of the formation is reddish arkosic sandstone, which grades into drabber thin-bedded siltstone and shale in cyclical sequences. [2]

The general depositional environment is reconstructed as a system of active streams running down from alluvial fans which developed along highlands further west of the basin. A few outcrops contain lenses of a conglomerate unit known as the Goose Creek Member. This unit preserves a diverse array of reddish brown to grayish green pebbles and cobbles derived from metamorphic rocks, alongside some sandstone and sandy siltstone. The pebbles and cobbles would have originated from the Proterozoic and Cambrian Catoctin Formation and Chilhowee Group exposed along the Blue Ridge Mountains. [3] [2]

The Catharpin Creek Formation is the youngest fully Triassic unit in the Culpeper Basin, before the occurrence of Triassic-Jurassic basalts associated with eruptions of the Central Atlantic Magmatic Province (CAMP). [1] Based on general stratigraphic characteristics, it is typically considered to be equivalent to the Passaic Formation of the Newark Basin. [4] The estimated age of the Catharpin Creek Formation is late Norian to Rhaetian according to fossils of conchostracans such as Shipingia olseni and Euestheria brodieana . [5]

Related Research Articles

The Rhaetian is the latest age of the Triassic Period or the uppermost stage of the Triassic System. It was preceded by the Norian and succeeded by the Hettangian. The base of the Rhaetian lacks a formal GSSP, though candidate sections include Steinbergkogel in Austria and Pignola-Abriola in Italy. The end of the Rhaetian is more well-defined. According to the current ICS system, the Rhaetian ended 201.4 ± 0.2 Ma.

<span class="mw-page-title-main">Chinle Formation</span> Geological formation in the western US

The Chinle Formation is an Upper Triassic continental geological formation of fluvial, lacustrine, and palustrine to eolian deposits spread across the U.S. states of Nevada, Utah, northern Arizona, western New Mexico, and western Colorado. In New Mexico, it is often raised to the status of a geological group, the Chinle Group. Some authors have controversially considered the Chinle to be synonymous to the Dockum Group of eastern Colorado and New Mexico, western Texas, the Oklahoma panhandle, and southwestern Kansas. The Chinle Formation is part of the Colorado Plateau, Basin and Range, and the southern section of the Interior Plains. A probable separate depositional basin within the Chinle is found in northwestern Colorado and northeastern Utah. The southern portion of the Chinle reaches a maximum thickness of a little over 520 meters (1,710 ft). Typically, the Chinle rests unconformably on the Moenkopi Formation.

The Newark Supergroup, also known as the Newark Group, is an assemblage of Upper Triassic and Lower Jurassic sedimentary rocks which outcrop intermittently along the United States East Coast. They were deposited in a series of Triassic basins approximately 190 million years ago as North America separated from Africa. The exposures extend from Nova Scotia to North Carolina. Related basins are also found underwater in the Bay of Fundy. The group is named for the city of Newark, New Jersey.

<span class="mw-page-title-main">Passaic Formation</span>

The Passaic Formation is a mapped bedrock unit in Pennsylvania, New Jersey, and New York. It was previously known as the Brunswick Formation since it was first described in the vicinity of New Brunswick, New Jersey. It is now named for the city of Passaic, New Jersey, which is near where its type section was described by paleontologist Paul E. Olsen.

<span class="mw-page-title-main">Pekin Formation</span>

The Pekin Formation is a Late Triassic (Carnian) geological formation in North Carolina. The Pekin Formation is specific to the Sanford Sub-Basin of the Deep River Basin of North Carolina, although it may be equivalent to the Stockton Formation of Pennsylvania, New Jersey, and New York. The Pekin Formation was deposited in a rift basin along the Atlantic margin of North America during the breakup of the supercontinent Pangaea during the Late Triassic. The most common rocks in the Pekin Formation are red to brown sandstones, representing a terrestrial fluvial (riverine) and floodplain environment in a hot, humid climate. It has yielded both abundant plant and animal fossils, including some of the oldest potential dinosaur footprints in the world and the large predatory crocodylomorph Carnufex carolinensis.

The Nam Phong Formation, which correlates to the Indosinian III Unconformity, is a geological formation in Thailand. It underlies the Khorat Group. It consists of resistant, red-brown micaceous sandstones, conglomerates, siltstones and mudstones of mainly fluvial origin. The sandstones are medium to very fine-grained and are usually calcareous. The conglomerates contain pebbles of quartz, brown and grey chert, and reddish brown siltstone. Cross bedding and plane-bed stratification are common in the sandstones and conglomerates. The sandstones and conglomerates make up approximately 30% of the formation. This sedimentary rock formation is found in Khon Kaen Province, Thailand. It is of Norian to Rhaetian age to age, and is notable for its fossils of early dinosaurs.

The Triassic Lockatong Formation is a mapped bedrock unit in Pennsylvania, New Jersey, and New York. It is named after the Lockatong Creek in Hunterdon County, New Jersey.

<span class="mw-page-title-main">Molteno Formation</span> Triassic geological formation in the Stormberg Group in Lesotho and South Africa

The Molteno Formation is a geological formation found in several localities in Lesotho and South Africa. It lies mainly south of Maseru, near Burgersdorp, Aliwal North, Dordrecht, Molteno, and Elliot. It extends as far north as Matatiele in the Eastern Cape. The formation's localities lie along the Drakensberg Mountains in Kwazulu-Natal, and near Ladybrand in the Free State of South Africa. The Molteno Formation is the lowermost of the three formations in the Stormberg Group of the greater Karoo Supergroup. The Molteno Formation represents the initial phase of preserved sedimentation of the Stormberg Group.

<span class="mw-page-title-main">Feltville Formation</span>

The Feltville Formation is a mapped bedrock unit primarily in New Jersey, with one known outlier in Pennsylvania and another one in New York. It is named for the Deserted Village of Feltville in Watchung Reservation, New Jersey, which is near where its type section was described by paleontologist Paul E. Olsen.

The East Berlin Formation is an Early Jurassic geological formation in New England, United States. Dinosaur footprints and trackways are abundant in this formation. These tracks include Eubrontes, Anchisauripus, and Anomoepus. Several museums, parks, and tourist attractions are based around the East Berlin Formation's dinosaur tracks, including Dinosaur State Park in Rocky Hill, Connecticut and Powder Hill Dinosaur Park in Middlefield, Connecticut.

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 208.5 million years ago. It was preceded by the Carnian and succeeded by the Rhaetian.

The Gettysburg Formation is a mapped bedrock unit consisting primarily of sandstones, conglomerates, and shales.

The Doswell Formation is a geologic unit of Upper Triassic age, part of the Newark Supergroup. The Doswell Formation was originally named to refer to a geological sequence which forms the lower part of the sedimentary fill of the Taylorsville Basin in Virginia and Maryland. This sequence was deposited by lakes and rivers in the developing rift basin. However, a 2016 study determined that several geological layers in Pennsylvania as well as the neighboring Richmond Basin of Virginia also qualified as components of the Doswell Formation.

<span class="mw-page-title-main">Culpeper Basin</span>

The Culpeper Basin is one of the Newark Supergroup's Triassic rift basins. It lies east of the Appalachian Mountains and extends from the Madison County—Orange County line in Virginia to Frederick, Maryland. A diverse group of sedimentary rocks including siltstone, sandstone, and conglomerate within the basin were intruded by igneous rocks, which caused thermal metamorphism at the contact with sedimentary rock.

The Bull Run Formation is a Late Triassic (Norian) stratigraphic unit in the eastern United States. Fossil fish bones and scales have been found in outcrops of the formation's Groveton Member in Manassas National Battlefield Park. Indeterminate fossil ornithischian tracks have been reported from the formation.

The Midland Formation is a Mesozoic geological formation in the Culpeper Basin of Virginia. It is a sedimentary unit which formed in a short period of time between the first two basalt flows in the basin: the Hickory Grove and Mount Zion Church basalts. The most common rocks in the formation are dark reddish interbedded sandstones and siltstones, representative of fluvial (stream) environments. Rare but fossiliferous calcareous shale and limestone also occurs, representing recurring lacustrine (lake) conditions. The Midland Formation is considered equivalent to the Shuttle Meadow Formation of the Hartford Basin, the Feltville Formation of the Newark Basin, and the Bendersville Formation of the Gettysburg Basin.

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 unit of the Chatham Group, overlying the Pekin Formation and underlying the Sanford Formation. Both of these encompassing formations are primarily red sandstone. The Cumnock Formation, on the other hand, represents a sequence of darker lacustrine (lake) or paludal (swampy/marshy) sediments deposited in a tropical climate. These primarily include shales and coal, with some thin layers of coarser sediment such as siltstone and sandstone.

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 group was originally named to refer to Triassic rocks specifically within the Deep River Basin of North Carolina. Later studies have utilized it to encompass Late Triassic strata in most other sedimentary basins in the Newark Supergroup.

<i>Oncodella</i> Extinct genus of jawless fishes

Oncodella is an extinct genus of Late Triassic conodont. The genus was given the type species Oncodella idiodentica by Mosher (1968), on the basis of fossils from the Late Triassic of Austria. However, Mosher (1969) later revised the species name to Oncodella paucidentata, since identical fossils from the same area were previously given the name Hindeodella paucidentata by Mostler (1967).

The Sanford Formation is a Late Triassic (Norian)-age geologic formation in North Carolina. It is mainly found in the Sanford sub-basin of the Deep River Basin, the southernmost of the large Mesozoic basins forming the Newark Supergroup. It is the highest unit of the Chatham Group, overlying the dark lake and swamp sediments of the Cumnock Formation. The Sanford Formation is composed primarily of coarse red sediments such as conglomerates, sandstones, and mudstones. The conglomerate layers contain pebbles of schist and slate, with the occasional large boulders of granite.

References

  1. 1 2 Weems, Robert E.; Olsen, Paul E. (1997-02-01). "Synthesis and revision of groups within the Newark Supergroup, eastern North America". GSA Bulletin. 109 (2): 195–209. doi:10.1130/0016-7606(1997)109<0195:SAROGW>2.3.CO;2. ISSN   0016-7606.
  2. 1 2 Lee, K.Y.; Froelich, A.J. (1989). "Triassic- Jurassic Stratigraphy of the Culpeper and Barboursville Basins, Virginia and Maryland". U.S. Geological Survey Professional Paper. 1472: 1–52. doi:10.3133/pp1472.
  3. Lindholm, R.C. (1979). "Geologic history and stratigraphy of the Triassic–Jurassic Culpeper basin, Virginia". Geological Society of America Bulletin. 90 (2): 1702–1736. Bibcode:1979GSAB...90.1702L. doi:10.1130/GSAB-P2-90-1702.
  4. Weems, Robert E.; Tanner, Lawrence H.; Lucas, Spencer G. (2016). "Synthesis and revision of the lithostratigraphic groups and formations in the Upper Permian?–Lower Jurassic Newark Supergroup of eastern North America". Stratigraphy. 13 (2).
  5. Kozur, Heinz W.; Weems, Robert E. (2010-01-01). "The biostratigraphic importance of conchostracans in the continental Triassic of the northern hemisphere" (PDF). Geological Society, London, Special Publications. 334 (1): 315–417. Bibcode:2010GSLSP.334..315K. doi:10.1144/SP334.13. ISSN   0305-8719. S2CID   131224365.