Every year, thousands of our fellow Americans visit Great Smoky Mountains National Park, in the heart of the southern Appalachian highlands. All visitors find refreshment in this mountain wilderness, some of them are also inspired by its deeper meanings - by observing the varied forests and other living things of the mountains, and by contemplating the long ages of the past during which the mountains and their living things must have evolved. These past ages can be deciphered by geologic study, which interprets first of all how the land has been shaped into its present form, and more remotely, the nature and history of the rocks from which the land has been carved.
The account which follows deals primarily with this more remote part of the geologic story - the rocks which compose the mountains. How the present mountains came into being is a later chapter of the story, interesting in itself, which deserves its own presentation in another place.
The present account summarizes the results of a long investigation of the rocks of the Great Smoky Mountains (1946-55) by geologists of the staff of the U.S. Geological Survey, in collaboration with those of the Tennessee Division of Geology. The technical details of this investigation have already been set forth at length in professional papers of the U.S. Geological Survey. The present account contains the gist of these findings about the rocks of the mountains, and is accompanied by a map and structure sections in which the surface and underground extent of the rocks are displayed.
This summary, by cutting through the many technical problems involved, will be useful to students interested in geology and the other natural sciences, and to a wider audience as well. Even so, to portray adequately the rocks of the mountains and their history involves at least some recourse to geologic terminology, so that all the assertions made herein may not be comprehensible to the general reader. As an aid to the reader, a glossary of the geologic terms used is therefore included at the end. For those readers who desire more detailed information regarding the findings so briefly summarized in this account, reference should be made to the more lengthy professional papers on which the account is based.