Deformation patterns in the southern Brazilian branch of the Dom Feliciano Belt: A reappraisal
Abstract
Structural mapping of key areas linked by reconnaissance investigations in the southern Brazilian portion of the Brasiliano/Pan-African Dom Feliciano Belt has shown the importance of large-scale flat-lying and strike-slip shear zones in the tectonic evolution of this belt. These zones of intense deformation form km-thick mylonitic belts in Brasiliano granites and supracrustal rocks as well as their Transamazonian/Eburnian basement. Structures developed within flat-lying shear zones under metamorphic conditions of amphibolite facies are interpreted as having formed during oblique collision between crustal blocks — the Kalahari Craton and the Magmatic Arc I — in which the direction of tectonic transport was NW-SE. Further collision between this assemblage and the Rio de La Plata Craton gave rise to a transpressive regime whose tectonic transport direction is indicated by regionally consistent NE/SW-oriented stretching lineations, parallel to the belt's length.
- Publication:
-
Journal of South American Earth Sciences
- Pub Date:
- January 1992
- DOI:
- 10.1016/0895-9811(92)90061-3
- Bibcode:
- 1992JSAES...5...77F