Georgia's Fall Line

As Dr. Rood mentioned in class, the geology of Georgia differs to the north and south of the geologic Fall Line. The Fall Line is a twenty mile wide boundary which runs through Georgia from the southwest to the northeast and provides a dividing point between the Piedmont and Coastal Plain regions. During the Mesozoic era, what is now called the Fall Line was the shore of the Atlantic Ocean. 



The Piedmont region predominantly features igneous and metamorphic rocks, while the Coastal Plain region predominantly features sedimentary rocks. Most likely, the regions were created by the collision of tectonic plates around 300 million years ago, which is the same time as the creation of the Appalachian Mountains. To the north and south of the Fall Line, dominant soil types differ as well. Georgia soil north of the Fall Line is predominantly a type of clay soil, while south of the Fall Line soil is predominantly a type of sand soil (http://www.georgiaencyclopedia.org/nge/Article.jsp?id=h-721).



As you move farther north in Georgia's rivers, the water becomes less navigable due to the exposed rocks found closer to and in the Piedmont region, so several historic river-cities are found along the Fall Line. In Georgia, Columbus, Macon, Milledgeville, and Augusta were all located near the Fall Line and one of Georgia's major rivers. Other cities in the South, including Tuscaloosa, Alabama, Columbia, South Carolina, and Richmond, Virginia, are also located on the Fall Line (http://www.gly.uga.edu/railsback/GAGeology.html#FL). These cities became trading centers because they were established as far upstream as boats were able to navigate.

Mississipi Cotton Boat (Google didn't have one for the Ocmulgee River that I could find.)

While the Ocmulgee River is no longer navigable by ships, its navigability during the nineteenth century allowed Macon to serve as a major trading center during the mid-1800s. Macon boasted several large-scale manufacturing centers, including bricks and textiles, but cotton was the main commodity carried by ships on the Ocmulgee. By the later part of the nineteenth century, the decreased water volume in the Ocmulgee, due to agricultural endeavors lessening rainwater runoff, meant the river was unnavigable without heavy dredging. Soon, carriage by rail became the main form of transporting goods and Macon became major rail-hub for a short time ( http://www.georgiaencyclopedia.org/nge/Article.jsp?id=h-782). 

This is the Atlantic Cotton Mill in Macon, GA



From geologic activity to commerce, the presence of the Fall Line has helped shape Georgia's history, especially in Macon. Currently, there are plans to connect Columbus, Georgia, and Augusta with a "Fall Line Freeway." The interstate would allow for easier transportation of goods between the three cities and beyond by providing a direct route between the three. The route may one day include a connection to highways leading to Mississippi and Louisiana. Even though transporting goods by river is no longer the main form of shipping, the presence of "Fall Line Cities" and their importance in commerce shows the effects of Georgia's Fall Line.