What is the top layer of rock inside of the smoky mountains. (Must be the exact rock type and already tried sedimentary ... idk which sedimentary though.)

Most of the rocks in Great Smoky Mountains National Park are sedimentary and were formed by accumulations of clay, silt, sand, gravel, and minor amounts of calcium carbonate in flat-lying layers.

Explanation:

Approximately 200-300 million years ago, drifting continents gradually collided in a climactic mountain building episode. As the continents collided, tremendous pressures were generated which deformed the once horizontal sedimentary rocks into folded structures. An entire belt of folded and faulted rocks extends over 2,000 miles from what is now Maine to Georgia and is known collectively as the Appalachian Mountains. The Great Smoky Mountains are but a small portion of that range.