The granitic rocks of the southeastern Piedmont have been divided into several groups on the basis of age, composition, and field appearance (Butler and Ragland, 1969a; Fullagar, 1971; Wagener and Howell, 1973; Wright and others, 1975): The Liberty Hill is one of the postmetamorphic, coarse-grained granitoids of the southern Appalachian Piedmont, a group whose field relations, petrology, chemistry, and ages have been reviewed by Fullagar and Butler (1979) and Speer and others (1980). Previous geologic mapping indicated that the Liberty Hill pluton has a cordierite-bearing, thermal-metamorphic aureole (Bell and others, 1974) which is similar to the contact aureoles of several of the other plutons in the same group.
This paper is a result of a study of the magmatic and postconsolidation evolution of these granites. Examination of the contact metamorphism offers a better opportunity for estimating intensive parameters of pressure, temperature, oxygen fugacity, and their variation following emplacement than does study of the granite alone. The results also provide constraints on the regional conditions during intrusion. In addition, the aureole of the Liberty Hill provides a clear picture of mineral chemistries and metamorphic reactions that occur in the contact metamorphism of low-grade slates dominated by a succession of continuous reactions.