Читать книгу Carolina Whitewater. A Paddler's Guide to the Western Carolinas онлайн

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Beyond the Blue Ridge to the east, the Carolinas drop out of the mountains onto the rolling plateau of the Piedmont. Extending from the Blue Ridge Escarpment to the Fall Line where the topography suddenly drops off onto the flat expanse of the Coastal Plain, the Piedmont descends at roughly 3.5 feet per mile with the terrain changing gradually from rolling hills to flat upland. Deeply cut by rivers and creeks, the hills of the Piedmont rise from 400 to 1,500 feet above sea level. Though the Piedmont is underlain by the same crystalline rock as the Blue Ridge region, it lacks the mountains’ high relief. Only occasionally are the rolling plains punctuated by a prominent hill. Comprising about 40 percent of the area of both Carolinas, the Piedmont is generally well developed and populated. Rivers flowing through the Piedmont, while lacking the high gradient and pristine setting of the mountains, are attractive, some endowed with a variety of rapids and falls.

The Coastal Plain region of the Carolinas begins at the Fall Line, where the underlying geology abruptly changes from hard crystalline rock to sandy loam over marl. Known locally as the “low country,” the plain was at the bottom of the Atlantic Ocean in past geologic ages. The Fall Line, where a dramatic drop in elevation occurs as one moves east from the Piedmont into the Coastal Plain, runs very roughly on the line of Falls-of-the-Roanoke to Durham to Columbia to Augusta (GA). Near the Fall Line the Coastal Plain consists of small hills. Moving toward the ocean, the terrain flattens. Swamp and marsh characterize the coastline corridor to the far east with many natural lakes occurring. Below the mouth of Cape Fear River, the coastal environs assume a more tropical look with black water (caused by tannic acid from decaying vegetation), thick groves of palmettos, magnolias, tall cypress draped with Spanish moss, and live oak.