Finite Strain Quantification in Cariris Velhos Metagranitoids of Alagoa Grande (PB)

The Cariris Velhos Metagranitoids are considered an important geological unit of the Transversal Zone (Borborema Province – NE Brazil). We evaluated the use of raw and processed digital images to obtain the deformation ellipsoid for the Cariris Velhos Metagranitoids using the Inertia Tensor and Intercepts methods. The ellipsoid symmetry of the deformed fabric was very similar for both methods, the Inertia Tensor and Intercepts, although with different anisotropy values. The orientations of the ellipsoid axes are similar to the orientation of geological structures observed in the field (principal foliations and mineral lineations). When analyzing the characteristics of the deformation ellipsoids obtained in this study, it is worth pointing out the strong orientation of the C-axis (foliation pole) and the predominance of ellipsoids associated with planar to planarlinear fabrics (flattening field). The deformation observed in the Cariris Velhos Metagranitoids is associated with the development under transpressive stress of regional Brasiliano shear zones.