Chattahoochee River National Recreation Area protects a 77 km (48 mi) stretch of the river between Buford Dam and the mouth of Peachtree Creek, across Cobb, DeKalb, Forsyth, Fulton and Gwinnett Counties, Georgia. Established on August 15, 1978, it covers approximately 3,965 hectares (9,798 acres) in 15 separate units — from Bowmans Island in the north through Settles Bridge, Jones Bridge, Island Ford, Vickery Creek and Cochran Shoals to the Palisades in the south.
Just north of Atlanta, it is an ecological oasis in a crowded region: home to more than 950 plant species and diverse wildlife, with undisturbed forests, wetlands, bluffs, ravines and open water. Archeological sites, historic structures and cultural landscapes record 10,000 years of human life along the river.
Slope Creek Shoals. Image from NPS’s page.
A river held in place by a fault
The recreation area runs along the Brevard Fault Zone, a 515 km (320 mi) feature that marks the boundary between the Appalachian Mountains and the Piedmont Plateau. Confined by the fault, the Chattahoochee is one of the oldest and most stable river channels in the United States.
That stability comes from the rock. The park’s geologic units are metamorphic rocks ranging from the Precambrian through the Paleozoic, and their hard, crystalline nature keeps the channel in place and holds up the area’s ridges, cliffs and palisades. The result is dramatic scenery: steep palisades, rocky shoals, sheer rock faces and exposed formations.
The named rock units
| Unit | Age |
|---|---|
| Long Island Creek Gneiss | Mesoproterozoic–Permian(?) |
| Ropes Creek Metabasalt | Neoproterozoic–Ordovician(?) |
| Crider Gneiss | Neoproterozoic–Ordovician(?) |
| Powers Ferry Member of the Stonewall Gneiss | Neoproterozoic–Ordovician(?) |
| Chattahoochee Palisades Quartzite | Cambrian(?) |
The recreation area is part of the Piedmont physiographic province and shares its geologic history and characteristic formations with a region stretching far beyond the park.
Palisades Shoals. Image from NPS’s page.
Mapping the park
This page draws on the NPS Geodiversity Atlas, a product of the Geologic Resources Inventory, which makes digital geologic maps and reports for more than 270 natural resource parks to support education, geoconservation and the management of a park’s living and non-living resources. A Soil Resources Inventory has also been completed for the recreation area; both are available through the NPS DataStore.
Sources
Based on "NPS Geodiversity Atlas—Chattahoochee River National Recreation Area, Georgia," National Park Service; a work of the United States government in the public domain.
Licence: CC0 1.0 (public domain) · Adapted from www.nps.gov
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