Aquia Formation
The Aquia Formation is a geologic sandstone formation that extends from the upper Chesapeake Bay to the James River near Hopewell, Virginia.[1] It consists of clayey, silty, very shelly, glauconitic sand.[1] Fossil records indicate that this stratigraphic unit was created during the Paleocene.[1]
When uncovered, it appears dark green to gray-green, argillaceous, with well sorted fine- to medium-grained sand and locally indurated shell beds.[2] It occurs between 0 to 100 feet thick.[2] Quartz and phosphatic pebbles and/or very coarse glauconitic quartz sand mark the base of the unit.[3] A few hard streaks of shells or thin "rock" layers are often reported but appear to be more abundant in the sections south of the James River.[3]
Fossils of the Aquia Formation
Sharks
- Carcharias hopei
- Cretolamna
- Otodus obliquus
- Paleohypotodus rutoti
- Striatolamia striata
- Squalus
Rays
Crocodillians
Turtles
Gastropods
References
- ↑ 1.0 1.1 1.2 Geology of the National Capital Region - Field Trip Guidebook. Reston, Virginia: U.S. Geological Survey, Department of the Interior. 2004. p. 270.
- ↑ 2.0 2.1 "Coastal Plain Rocks and Sediments". Geological Maps of Maryland. Maryland Geological Survey. 1968. Retrieved 21 January 2015.
- ↑ 3.0 3.1 Powars, D.S.; Bruce, T.S. (2000). The Effects Of The Chesapeake Bay Impact Crater On The Geological Framework And Correlation Of Hydrogeologic Units Of The Lower York-James Peninsula, Virginia. United States Geological Survey. Retrieved 22 January 2015.