Aquia Formation

The Aquia Formation is a geologic sandstone formation that extends from the upper Chesapeake Bay to the James River near Hopewell, Virginia. It consists of clayey, silty, very shelly, glauconitic sand.Fossil records indicate that this stratigraphic unit was created during the Paleocene.

When uncovered, it appears dark green to gray-green, argillaceous, with well sorted fine- to medium-grained sand and locally indurated shell beds. It occurs between 0 and 100 feet thick.Quartz and phosphatic pebbles and/or very coarse glauconitic quartz sand mark the base of the unit. 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.

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