Potomac Group

Potomac Group
Stratigraphic range: Cretaceous, Aptian–Turonian
View of Timber Neck showing the Arundel, Patapsco and Raritan Formations of the Potomac Group
TypeGroup
Sub-unitsPatuxent Formation, Arundel Formation, Patapsco Formation, Raritan Formation, Potomac Formation (?)
UnderliesRaritan Formation, Magothy Formation
OverliesBoonton Formation
Location
Region Delaware,  Maryland,  New Jersey,  Virginia
Country United States
Exposure of part of the Potomac Group at Elk Neck State Park, Maryland

The Potomac Group is a geologic group in Delaware, Maryland, New Jersey, and Virginia. It preserves fossils dating back to the Cretaceous period. An indeterminate tyrannosauroid and Priconodon crassus, a nodosaurid, are known from indeterminate sediments belonging to the Potomac Group.[1] The Potomac Group was initially believed to have been Late Jurassic in age by Othniel Charles Marsh[2] but later studies, such as Clark (1897), have found that the Potomac Group is in fact Early-Late Cretaceous (Aptian-Turonian) in age.[3] The most famous member of the group is the Arundel Formation, which preserves a high diversity of terrestrial vertebrate fauna and provides the most comprehensive look at the dinosaurian fauna of eastern North America during the Early Cretaceous.[4]

  1. ^ Brownstein, Chase Doran (2018). "A Tyrannosauroid from the Lower Cenomanian of New Jersey and Its Evolutionary and Biogeographic Implications". Bulletin of the Peabody Museum of Natural History. 59 (1): 95–105. doi:10.3374/014.058.0210. ISSN 0079-032X.
  2. ^ Marsh, O.C. (1888). Notice of a new genus of Sauropoda and other new dinosaurs from the Potomac Formation. American Journal of Science 135:89-94.
  3. ^ Clark, W.B., (1897), Outline of present knowledge of the physical features of Maryland: Maryland Geological Survey Volume Series, v. 1, pt. 3, p. 172-188.
  4. ^ [email protected], Joseph A. Frederickson~Sam Noble; [email protected], Thomas R. Lipka~Sam Noble; [email protected], Richard L. Cifelli~Sam Noble (2018-08-28). "Faunal composition and paleoenvironment of the Arundel Clay (Potomac Formation; Early Cretaceous), Maryland, USA". Palaeontologia Electronica. doi:10.26879/847. Retrieved 2024-10-28.{{cite web}}: CS1 maint: numeric names: authors list (link)