Raritan Formation

Raritan Formation
Stratigraphic range: Turonian
Outcrop of the Raritan Formation near Rocky Point above Round Bay, Severn River, Anne Arundel County, Maryland
Type	Sedimentary
Unit of	Potomac Group
Sub-units	Raritan Fire Clay, Farrington Sand Member, Woodbridge Clay Member, Sayreville Sand Member, South Amboy Fire Clay Member
Underlies	Magothy Formation
Overlies	Newark Supergroup, Patapsco Formation
Location
Region	New Jersey, New York, Maryland
Country	USA
Type section
Named for	Raritan Bay
Named by	G. H. Cook (1888)[1]

The Raritan Formation is a Cretaceous (Turonian) sedimentary geologic formation of the Atlantic Coastal Plain.

Overview

The formation was first described in 1888 by G. H. Cook, who measured sections in the vicinity of Raritan Bay in New Jersey.^[1] It was extended into Maryland by William Bullock Clark in 1893.^[2]

The formation is described in the USGS publication Tolchester folio, Maryland (1917) as follows:

The formation consists of diverse materials similar to those composing the Patapsco formation, except that, in general, the clays are not so highly colored. White and buff sands; stratified light chocolate-colored sandy clays, in places containing leaf impressions; light-colored argillaceous sands and sandy clays (Fuller's earth); and white, yellow, drab, bluish-drab, and variegated clays all occur in deposits of this age. The variegated clays are well exposed in the steep bluff at Worton Point (see photo below). The delicate pinkish tints which they present at many places have given rise to the local name "peach-blossom clays."^[3]

• 
  Vertically jointed clay of Raritan Formation in wave-cut cliff, Worton Point, Kent County (c. 1917)
• 
  The White Rocks off of Rock Point in Anne Arundel County are composed of lithified sands of the Raritan Formation (c. 1917)

Fossils

Dinosaur remains are among the fossils that have been recovered from the formation, although none have yet been referred to a specific genus.^[4] A tyrannosauroid similar to Appalachiosaurus is known from the formation.^[5]

Many plant fossils have been recovered from the Raritan.^[2] The formation hosts the New Jersey Amber deposits.

See also

• Earth sciences portal
• Paleontology portal
• Dinosaurs portal

• List of dinosaur-bearing rock formations
  • List of stratigraphic units with indeterminate dinosaur fossils

References

1. Cook, G.H., 1888, Report of the subcommittee on the Mesozoic: American Geologist, v. 2, p. 257-268.
2. Berry, Edward Wilber (1911). The Flora of the Raritan Formation. Trenton, New Jersey: Geological Survey of New Jersey.
3. Miller, B.L.; Mathews, E.B.; Bibbins, A.B.; Little, H.P. (1917). Tolchester folio, Maryland (Report). Folios of the Geologic Atlas. U.S. Geological Society. doi:10.3133/gf204. hdl:1969.1/3671. ISBN 0607728965.
4. Weishampel, David B.; Dodson, Peter; Osmólska, Halszka (2004). "Dinosaur distribution". The Dinosauria, 2nd edition. Berkeley: University of California Press. pp. 517–607. ISBN 0-520-24209-2.
5. Brownstein, Chase D. (2018-02-08). "The biogeography and ecology of the Cretaceous non-avian dinosaurs of Appalachia". Palaeontologia Electronica. 21 (1): 1–56. doi:10.26879/801. ISSN 1094-8074.

• Weishampel, David B.; Dodson, Peter; Osmólska, Halszka (2004), The Dinosauria, 2nd edition, Berkeley: University of California Press, pp. 1–880, ISBN 0-520-24209-2, retrieved 2019-02-21