Carolina Environmental Diversity Explorations

Clays of the Piedmont · By Dirk Frankenberg

Map of North Carolina showing Seagrove, Town Creek Indian Mound, and the Pee Dee River

A map of the sites visited in this field trip. (More about the map)

North Carolina’s landmass has twice been subjected to major bouts of mountain building followed by erosion. The mountain building events have been described in another field trip in this series, the Roan Mountain Highlands. The remnants of the erosion of these mountains have been described in the Lonely Mountains field trip. The material that was eroded away from our mountains makes up the soils and sediments of the Piedmont, coastal plains, and seacoast. Thirteen thousand feet of erosion products lie under your feet when you stand on a North Carolina ocean beach. The beach sands were carried farthest from their upland source because fine sand is the sediment type most easily moved by flowing water. Most geologists think that the sand hills section of the state was formed when rivers from the mountains carried large sand supplies with them.

The story of this field trip, though, is not about the sand that went to the beach and the sand hills, but rather the clays that eroded from other mountain minerals and settled in the Piedmont. The field trip will begin by showing you how secondary and primary clays are recovered from Piedmont environments. Then we will look at the uses to which different inhabitants have put the Piedmont’s clay resources — first the work of Native Americans over two millennia ago, then the utilitarian pots made by Europeans in the Piedmont, and finally the wares of modern potters.

Definitions

erosion n.
Natural processes, including weathering, dissolution, abrasion, corrosion, and transportation, by which material is worn away from the earth's surface.
remnant n.
Something left over; a remainder.
sediment n.
Solid fragments of inorganic or organic material that come from the weathering of rock and are carried and deposited by wind, water, or ice. Sediments may also be formed from chemical, biochemical, or biological materials. [more]
mineral n.
A naturally occurring, homogeneous inorganic solid substance having a definite chemical composition and characteristic crystalline structure, color, and hardness. [more]
primary clay n.
Any clay formed in place by the chemical and physical weathering of rock.
clay n.
A sedimentary material with grains smaller than 0.004 millimeters in diameter.
utilitarian adj.
Serving or capable of serving a useful purpose; functional, handy, practical, useful.
ware n.
A specific type of pottery or other manufactured good; more generally, any product that is bought and sold.