| 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.