The Borborema Strike-Slip Shear Zone System (NE Brazil): Large-Scale Intracontinental Strain Localization in a Heterogeneous Plate

Abstract Large-scale strike-slip faults are fundamental tectonic elements of the continental lithosphere. They constitute plate boundaries (continental transforms), separate terranes with contrasting geological histories within accretionary orogens, or accommodate heterogeneous deformation in intracontinental settings. In ancient where deeper levels crust exposed, these expressed as shear zones materialized by up to tens km-wide mylonitic belts. The Borborema zone system northeastern Brazil is one largest and best-exposed systems world, cropping out over 250,000 km2. Here, we review its main geophysical, structural, petrologic, geochronologic characteristics discuss factors controlling development. This complex scale composed a set NE- NNE-trending dextral from which there two major E-trending horse-tail terminations into transpressional belt branch, well several smaller NE-trending sinistral zones. marked extensive linear curvilinear magnetic gradients, implying their continuation at depth. migmatite amphibolite-facies mylonites, but entire shows evidence late lower temperatures. developed during stages Neoproterozoic Brasiliano (Pan-African) orogeny (mainly 590 560 Ma), postdating more than 20 Ma stage contractional deformation. Localization shearing this intraplate setting was controlled rheological contrasts between blocks distinct Paleoproterozoic histories, presence preorogenic rifts, craton geometry, enhanced magmatic activity, highlighting importance heterogeneity nucleation evolution.