Pan-African intraplate deformation in the Northern Prince Charles Mountains, East Antarctica

Abstract

New structural and metamorphic data coupled with U-Pb SHRIMP zircon and Rb-Sr step-leach biotite ages help constrain a period of Early Palaeozoic (Pan-African) deformation recognised in the northern Prince Charles Mountains, east Antarctica. This period of deformation is accommodated along discrete northeast trending mylonites that preserve up-dip reverse kinematics with dominantly southeast over northwest vergence. Ambient P-T conditions of 524 ± 20°C and 7.6 ± 4 kbar accompanied deformation. This phase of deformation post-dated the intrusion of planar felsic dykes that yield ages of c. 550 Ma and pre-dated Rb-Sr biotite ages of c. 475 Ma that record cooling of the terrane below c. 300°C. T..