I visited Tallulah Gorge a few years before I started writing this blog, so at the time I didn’t think to write down my observations. I can’t remember where I put the photos I took of that trip or if I even took any. However, I found plenty of Tallulah Gorge photos online. I do remember walking down a long flight of manmade stairs to the bottom of the gorge and on the way down coming face to face with a black vulture that was perched on a ledge. I saw blueberry and blackberry growing on the canyon wall. And I recall swimming in a very cold reservoir nearby. Lately, I’ve been reading a new book, Roadside Geology of Georgia, by Pam Gore and William Witherspoon. Their page on Tallulah Gorge reminded me of my trip there. I didn’t realize Tallulah Gorge had such a fascinating geological history.
Location of Habersham County. Tallulah Gorge is in this county.
The headwaters of the Tugaloo River eroded backwards upstream from the Tugaloo and captured the Tallulah and Chattooga Rivers both of which formerly flowed into the Chattahoochee River.
Tallulah Gorge is the 4th deepest gorge east of the Mississippi.
Tallulah Falls. The sudden drop in elevation when the Tugaloo River eroded backward into the Gainesville Ridge created these falls.
The Gainesville Ridge separates the Chattahoochee River drainage from that of the Savannah River. All streams on the west side of the ridge empty into the Chattahoochee River, while all streams on the east side of the ridge flow into the Savannah River or its tributaries. Formerly, the Chattooga and Tallulah rivers were tributaries of the Chattahoochee River. But the headwaters of the Tugaloo River eroded upstream into the Gainesville Ridge capturing the Tallulah and Chattooga Rivers. These 2 rivers changed course making a sharp right angle turn through the Tugaloo River which empties into the Savannah River. It’s a classic example of what geologists refer to as stream capture. Geologists believe this stream capture event occurred “recently”, but I haven’t been able to find any studies of the exact age of the event, and I think scientists have not determined the exact timing of this dramatic occurrence. Recently in geological time could be 10 million years. Nevertheless, scientists believe the steepness of the gorge is evidence the stream capture occurred relatively recently. Some of the cliffs are 600 feet high. Geologists believe the gorge is geologically young because not enough time has passed for the high cliffs to erode away. In older river and stream incisions, water eventually erodes the sides back, creating broad gently sloped valleys. But at Tallulah Gorge, not enough time has passed for this to happen.
The rock along Tallulah Gorge is made of erosion resistant quartzite which is sandstone that has been metamorphized. There is no Chattooga River gorge because the rock along that river is less resistant to erosion. When the Tugaloo River eroded backwards and captured these 2 tributaries, the elevation suddenly lowered, creating the falls. This change in elevation is the reason the Chattooga river is known for its white water rafting.
There are 2 types of environments in the vicinity of the Tallulah Gorge. The cliffs provide nesting habitat for many species of birds (See https://markgelbart.wordpress.com/2013/05/19/piedmont-cliff-ecology/). In pre-Columbian times bald and golden eagles and peregrine falcons likely nested here. An acidic pine/oak woodland and forest grow on the rim of the gorge. Plant species composition includes white pine, Virginia pine, table mountain pine, pitch pine, shortleaf pine, southern red oak, rock chestnut oak, scarlet oak, blackjack oak, red maple, sourwood, persimmon, mountain laurel, rhododendron, blueberry, and greenbrier. This is the southernmost range limit of the Carolina hemlock. Monkey-faced orchid and persistent trillium are rare plants that favor this moist, water-splashed environment.
The Soque River may be a remnant of the Chattooga and Tallulah Rivers before they were diverted from the Chattahoochee River Drainage to the Savannah River Drainage. This is a beautiful small river with little public access.
Deep Creek and the Soque River are likely remnants of the Chattooga and Tallulah Rivers before they were diverted from the Chattahoochee River Drainage. There are many species of mussels common to both the Chattahoochee and Savannah Rivers. The Tugaloo stream capture event must explain how bivalves from the Chattahoochee Drainage colonized the Savannah. For a while during this stream capture event, water must have flowed from the Savannah to the Chattahoochee as well because mussels originating from the former also made it to the latter. However, it’s not clear how thie mussel exchange from the Savannah to the Chattahoochee occurred.
Tags: Chattahoochee River, Chattooga River, Savannah River, Soque River, Tallulah Falls, Tallulah Gorge, Tugaloo stream capture
GeorgiaBeforePeople 
February 8, 2014 at 10:32 pm |
I’ve never heard of the Soque River!
I’ve been to the Tallulah Gorge a couple of times. First time I saw it I was stunned. I’d never realized there was anything like it in Georgia. The last time I was there I hiked down to the bottom. Water flow in the Gorge is much reduced because so much of the river flow is diverted for power production. My father-in-law used to go there in his capacity as an adviser from Duke Power.
I’d like to nab one of the permits that you need to go directly into the Gorge. I think they only give out 40 or so per day. A couple had gotten one of the permits when I was at the end of the stairs and went on past the gate and down to the river. They really regulate human traffic beyond the stairs and overlooks.
February 9, 2014 at 1:30 pm |
You probably never heard of the Soque River because it’s only 30 miles long and is entirely confined to Habersham County before it empties into the Chattahoochee.
August 4, 2014 at 3:46 am |
First of all, that’s not a brown trout (although you are right about the “non-native” part); it is a rainbow. And it’s also a pet–a fish that is stocked and fed to grow unnaturally large for it’s environment.
If you’re proud of this, you might also like going to the Atlanta zoo and shooting one of the beasts there at point-blank range from behind the safety of a fence.
About a month ago my 8-year old caught a trophy fish on a little creek that you can almost jump across in Rabun Co. That fish was about six times the size of your “brown” trout. “Six times”, that is in perspective to it’s environment, the fact that it was a natural fish (not a fed pet), and it the average size for that stream.
But he’s a real fisherman.
August 4, 2014 at 12:37 pm |
Thanks for informing me of my error. I will edit in the correction. I found that photo on the internet and cut and pasted it. The man in the photo claimed it was a wild brown trout caught in the Soque River.
Before you vent your fury at someone on the internet, you should try to read more carefully. I never claimed to have been the one that caught that fish.
You would never have been this nasty to me in person.
August 23, 2014 at 12:19 pm |
[…] Chattahoochee, explaining how speciation occurred between shoal basses from these 2 rivers. (See:https://markgelbart.wordpress.com/2014/02/06/tallulah-gorge/) Similar geological events probably explain the evolutionary divergence of other shoal […]