Geology of North Carolina

The region experienced igneous activity and the addition of new terranes and orogeny mountain building events throughout the Paleozoic, followed by the rifting of the Atlantic Ocean and the deposition of thick sediments in the Coastal Plain and offshore waters.

The Bakersville mafic dike swarm from 734 million years ago along with the peralkaline granites of the Crossnore Complex and bimodal volcanic rocks atop the crystalline basement point to the rifting of the proto-North American continent Laurentia.

[4] More deeply buried crystalline basement rock that remains poorly understood underlies eastern North Carolina, although the present geology of the area at the surface is dominated entirely by the Atlantic coastal plain, which resulted from sediment eroded off the Appalachian Mountains that began to steadily form in the Cretaceous.

The Atlantic coastal plain continued to build out to sea during the Cenozoic and the current sand, clay and gravel at surface on dry land and in rivers, lakes, and nearshore water all formed during the last 2.5 million years of the Quaternary.

The smaller Riverbend Formation lies just to the east, running north and south from Jackson with a limestone unit and abuts the oyster shell mounds and clay sands of the Pollocksville Member.