The Great Smoky Mountains National Park of North Carolina and Tennessee is part of the Blue Ridge province of the southern Appalachians.  The highest mountains in eastern part of North America are in the Blue Ridge, and some of the highest peaks in this province are in the Great Smoky Mountains (King, 1968; Schultz et. al, 2000).

The rocks of Great Smoky Mountains are metasedimentary rocks that originally formed from sediments deposited in a marine basin that formed as Laurentia rifted apart to form the Iapetus Ocean approximately 800 to 450 Ma ago (Schultz et. al, 2000).  As a result of the Alleghanian orogeny, rocks of the Great Smoky Mountains were complexly folded and faulted (King, 1968; Southworth, et. al, 2000).  Early movement along nearly flat-lying thrust faults such as the Greenbriar and the Great Smoky faults, pushed sheets of older rocks tens to hundreds of miles westward, up and over younger rocks.  Later deformation along the higher angle Gatlinburg fault resulted in both dip-slip and strike-slip movement (King, 1968).

Most of the rocks exposed in the park are part of the Ocoee Supergroup.  These late Precambrian aged sedimentary rocks have been metamorphosed to varying degrees, from low grade in the northwest (identified by the presence of chlorite), to higher grade in the southeast, characterized by both staurolite and kyanite (King, 1968).  Despite pervasive metamorphism, original sedimentary structures such as bedding are well preserved, and thus, rocks in this area are still described as sedimentary rather than metamorphic rocks.  The largest subdivision of the Ocoee Supergroup, the Great Smoky Group, includes the most prevalent rocks in the park -- the Elkmont and Thunderhead Sandstones, and the Anakeesta Formation (King, 1968).  Both the Elkmont and the Thunderhead Sandstones are gray, thickly bedded sandstones composed of mostly quartz, potassium feldspar and some plagioclase (King, 1968).  The Anakeesta Formation consists of dark silty and argillaceous rocks that have been altered to slate, phyllite and schist (King, 1968).