Closer view of an ancient shoreline

Figure 2. The vertical extent of Swansboro Ridge is evident in this sand pit. (Photograph by the author. More about the photograph)

In Figure 2 we can see the vertical extent of the ridge shown in Figure 1. This is a sand pit dug into the Swansboro Ridge near Bear Island. As you can see, the ridge rises more than 40 feet from the water table (the pond in the lower left background) to the undisturbed ground surface in the upper right foreground.

Note that the entire wall of the pit is made of fine white sand — exactly the kind of sand found in sand dunes today. The reason for the similarity is clear: this sand and the ridge it forms were both part of a shoreline like today’s. The sand that this shoreline contains has been eroded away further seaward and has been incorporated into the high sand volume barrier islands you are about to visit.

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