Parallel Ridges in the Brevard Zone
Vinings, Georgia

On a shaded-relief map, many segments of the Brevard Zone show rhythmically-spaced parallel ridges, oriented along the Zone's northeast strike. These ridges are responsible for the Chattahoochee River's northeast-to-southwest course through north Georgia; they intercept drainage that would otherwise flow southeast toward the Atlantic Ocean, diverting it southwest toward the Gulf of Mexico. In northwest Atlanta, the Chattahoochee breaks through these ridges, probably by following sets of joints (fractures) in the ridge rock.

The Gold Belt and the Murphy Belt show similar sets of parallel ridges, suggesting structural similarity among these features.

Atlanta skyline
Looking southeast from a ridge in Vinings
across two or three intervening parallel ridges