River Bend Formation

The River Bend Formation is a limestone geologic formation in North Carolina. It preserves fossils dating back to the Paleogene period.

River Bend Formation
Stratigraphic range: Oligocene
TypeFormation
Lithology
Primarylimestone
Location
Region North Carolina
Country United States
Type section
Named forRiver Bend Estates along the Trent River

Description

The River Bend formation is a limestone formation characterized by mollusc molds, barnacle hashes, bivalves, and sandy limestone layers.[1] Fossils indicate that the formation was deposited during the middle to late Oligocene.

History

Originally, the River Bend formation was part of a limestone unit called the Trent Marl. Further research split off the Miocene Belgrade Formation from the Trent Marl and considered the River Bend formation as part of the Castle Hayne Limestone.[1] The River Bend formation was then identified as an Oligocene limestone and broken out from the Castle Hayne Limestone. The Trent Marl nomenclature is no longer used.

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See also

References
  1. Ward, Lauck W.; Lawrence, David R.; Blackwelder, Blake W. (1979). "Stratigraphic revision of the middle Eocene, Oligocene, and lower Miocene; Atlantic Coastal Plain of North Carolina" (PDF). U.S. Geological Survey Bulletion. 1457-F: 3–10. Retrieved 26 June 2018.


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