Geometry and kinematics of the Afogados de Ingazeira shear zone, northeastBrazil

Numerous transcurrent NE-SW mainly sinistral, and E-W dextral-trending shee r zones transect Borborema Province, northeastern Brazil. The most importan t kinematic event involving those shear zones reflects deformation related to the Brasiliano (Pan-African) tectonic cycle. The Afogados da Ingazeira s hear zone (AISZ) is probably the most important of the NE-SW-trending linea ments, having continuity for over 250 km. Field work associated with petrog raphic studies (including quartz e-axis patterns), conducted in an area enc ompassing the north-central part of this shear zone, indicate that sinistra l transcurrent deformation was responsible for the main banding/foliation ( C-S) observed in the rocks. Mineral assemblages and microstructural feature s are suggestive of a deformational history starting under low- to medium-a mphibolite facies (thermal peak conditions) and decreasing until greenschis t facies.