Recent reconnaissance geologic mapping and aeromagnetic data show that long, continuous diabase (dolerite) dikes occur throughout the eastern Piedmont of North Carolina. The new knowledge of locations and patterns of diabase dikes presenteee on the map accompanying this reports supports observations by earlier workers that diabase dikes in the Appalachain region cut across all other structures and thus reflect deep-seated stresses. One twelve page booklet and a map plate (approximately 3'x2.5'). By E.R. Burt, P.A. Carpenter, III, R.D. McDaniel, and W.F. Wilson, 1978.