Aquia Formation

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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 and 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[edit]

Sharks[edit]

Rays[edit]

Crocodillians[edit]

Turtles[edit]

Gastropods[edit]

References[edit]

  1. ^ a b c Geology of the National Capital Region - Field Trip Guidebook. Reston, Virginia: U.S. Geological Survey, Department of the Interior. 2004. p. 270. 
  2. ^ a b "Coastal Plain Rocks and Sediments". Geological Maps of Maryland. Maryland Geological Survey. 1968. Retrieved 21 January 2015. 
  3. ^ a b 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.