The crystalline area of Georgia, comprising more than 17,000square miles, was studied for the occurrence of diabase. Fifty-seven new dikes were mapped and specimens from them examined under the microscope. No sill-like bodies were encountered and no flows or remnants of flows exist in the area.
No definite age can be given to the diabase in Georgia, but on the basis of contacts with certain rock units and deep well samples from Florida, the age has been set as late Triassic.
Contact metamorphism is seldom present, and then only slightly so; no mineral concentrations were found; and the dikes have little, if any, influence on the drainage patterns of the region.