The Detroit River Group is a geologic group in Michigan and Ohio. It preserves fossils dating back to the Devonian period.
The Conemaugh Group is a geologic group in West Virginia, Pennsylvania, Ohio, and Maryland. It preserves fossils dating back to the Carboniferous period.
The Black Creek Group is a geologic group in North Carolina. It preserves fossils dating back to the Late Cretaceous period.
The Chesapeake Group is a geologic group in Maryland, Virginia, Delaware, and North Carolina. It preserves mainly marine fossils dating back to the Miocene and Pliocene epochs of the Neogene period. This group contains one of the best studied fossil record of Neogene oceans in the world. Professional Paleontologists and amateur fossil hunters alike collect from this group intensely. The Calvert Cliffs stretch the length of Calvert County, Maryland and provide the best continuous stretch of the Calvert, Choptank, and St. Marys Formations. Ward (1985) recommended including the Old Church Formation in this group.
The Dan River Group is a geologic group in North Carolina. It preserves fossils dating back to the Triassic period.
The Cid Formation is a metavolcanic rock and mudstone geologic formation in North Carolina. It consists of a lower unnamed mudstone member with intermittent volcanic flows and the Flat Swamp Member, which is characterized by pyroclastic flows. It preserves fossils dating back to the Ediacaran period.
The Millingport Formation is a geologic formation in North Carolina. It preserves fossils dating back to the Ediacaran period.
The Bear Bluff Formation is a geologic formation in North Carolina. It preserves fossils dating back to the Neogene period.
The Chowan River Formation is a geologic formation in North Carolina. It preserves fossils dating back to the Neogene period.
The Duplin Marl is a geologic formation in North Carolina. It preserves fossils dating back to the Neogene period.
The Pamlico Formation is a geologic formation in North Carolina. It preserves fossils dating back to the Neogene period. The name was suggested by L.W. Stephenson in the North Carolina Geological and Economic Survey journal in 1912
The Pollocksville Formation is a geologic formation in North Carolina. It preserves fossils dating back to the Neogene period.
The Trent Formation is a geologic formation in North Carolina. It preserves fossils dating back to the Neogene period.
The New Bern Formation is a geologic formation in North Carolina. It preserves fossils dating back to the Paleogene period.
The River Bend Formation is a limestone geologic formation in North Carolina. It preserves fossils dating back to the Paleogene period.
The Black Mingo Group is a geologic group in South Carolina composed of dark grey to black clays, shales, laminated sandy shales, and yellow-red sands. The group's name comes from Black Mingo Creek where outcrops of the group are exposed. The bottom boundary is an unconformity with Cretaceous deposits. It preserves fossils dating back to the Paleogene period.
The Cooper Group is a geologic group in South Carolina. It preserves fossils dating back to the Paleogene period.
The Rhems Formation, also called the Rhems Shale, is a geologic formation in South Carolina. The Rhems Formation is considered part of the Black Mingo Group. It was named after Rhems, SC which is located five miles from the type locality at Perkins Bluff. The unit is a light gray to black shale interlaminated with thin seams of fine-grained sand and mica with some layers partially silicified. It preserves fossils dating back to the Paleogene period.
The Duplin Formation is a geologic formation in North and South Carolina. It preserves fossils dating back to the Neogene period, Pliocene epoch.
The North Park Formation is a geologic formation in Wyoming. It preserves fossils dating back to the Neogene period.
Arkansas, 
North Carolina 
United States 
