Castle_Hayne_Limestone Knowpia

Castle Hayne Limestone
Castle Hayne Limestone
Stratigraphic range: Eocene
Type	Formation
Sub-units	New Hanover Member, Comfort Member, Spring Garden Member
Lithology
Primary	limestone
Other	marl
Location
Region	North Carolina
Country	United States
Type section
Named for	Castle Hayne, North Carolina

The Castle Hayne Limestone (also called the Castle Hayne Formation) is a geologic formation in North Carolina. It consists of cobble to pebble sized clasts, usually rounded, coated with phosphate and glauconite in a limestone matrix. The Castle Hayne Limestone is known for containing fossils dating back to the Paleogene period. It preserves many of North Carolina's renowned Eocene fossils. It is named after the locality of Castle Hayne in New Hanover county, though the formation itself stretches over several counties.

Description edit

The Castle Hayne Formation is divided into three submembers: the New Hanover member, the Comfort Member, and the Spring Garden Member.^[1] The New Hanover member is the oldest member and is characterizes by cobbles and pebbles, fine sand, glauconite, and phosphate in a fine limestone matrix. The most common fossils are shark and ray teeth. Index fossils place this member in the middle Eocene. The Comfort member lies above the New Hanover member. It contains bryozoa and sea urchin fossils and beds of glauconite and phosphate pebbles that mark breaks in deposition. The Comfort member was deposited in the late middle Eocene and is overlain by the Spring Garden member. The Spring Garden member is a siliceous rock cemented with calcite and containing detrital phosphate. Mollusc bivalves account for up to 75% of the composition in some areas and molds of molluscs shells filled with silica are common. Index fossils indicate this member was also deposited in the late middle Eocene.

Fossils edit

Invertebrates edit

Molluscs edit

^[2]

Genera	Species	Notes
Chione	C. sp
Crassatella	C. wilcoxi C. sp	A crassatellid bivalve.
Ensis	E. sp
Flemingostrea	F. sp
Giganostrea	G. trigonalis	An extinct group of oyster.
Glyptoactis	G. sp
Panopea	P. sp	A close relative of the modern geoduck.
Pecten	P. membranosus	An extinct bivalve that belonged to the same genus as most modern scallops.
Pholadomya	P. sp
Plicatula	P. filamentosa
Venericardia	V. sp

Cephalopods edit

Genera	Species	Notes	Images
Anomalosaepia	A. vernei A. mariettani A. alleni A. andreane A. sp	An extinct group of cuttlefish that was also found in Egypt and belonged to the family Anomalosaepiidae.
Aturia	A. alabamensis	Belongs in its own family: the Aturiidae.
Beloptera	B. sp	Another extinct group of cuttlefish that was found in several localities in Europe.
Conchorhynchus	C. furrus	Has not been classified into any specific cephalopod group yet.
Eutrephoceras	E. carolinensis	First originated during the Cretaceous period.	E. dorbignyanum, a related species.
Rhyncolites	R. sp R. minimus R. aturensis	An extinct group of nautiloid that has not yet been classified into any specific family.

Vertebrates Fossils edit

Mammals edit

Cetaceans edit

Genus	Species	Notes	Images
Zygorhiza	Z. kochii	A close relative of the well-known archaeocete Dorudon.
Basilotritus	B. wardi	A basilosaurid that was originally classified under Eocetus.

Sirenians edit

Genus	Species	Notes	Images
Protosiren	P. sp	A prehistoric manatee relative that is also known from Eurasia.

Cingulates edit

Genus	Species	Notes	Images
Holmesina	H. sp	A pampathere that resembled a giant armadillo. It arrived to North America after migrating from South America.

Reptiles edit

^[3]

Squamates edit

Genus	Species	Notes	Images
Palaeophis^[4]	P. grandis	An extinct species of giant marine snake from the family Paleophiidae.

Turtles edit

Genus	Species	Notes	Images
Cheloniidae indet		Known by plate, shell, and plastron fragments.

Crocodilians edit

Genus	Species	Notes	Images
Crocodylia indet		Known by vertebra.

References edit

^ 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 Bulletin. 1457-F: 3–10. Retrieved 26 June 2018.
^ "Online Collections | North Carolina Museum of Natural Sciences". collections.naturalsciences.org. Retrieved 2016-03-15.^{[permanent dead link]}
^ "Online Collections | North Carolina Museum of Natural Sciences". collections.naturalsciences.org. Retrieved 2016-03-19.^{[permanent dead link]}
^ "Fossil ID Quiz" (PDF). JANUS. North Carolina Fossil Club. pp. Name is on Page 5, Location is listed next to fossil #11 on Page 7. Archived from the original (PDF) on 2016-04-02.