Architecture of major precambrian tectonic boundaries in the northern part of the Dom Feliciano Orogen, southern Brazil: Implications for the West Gondwana amalgamation

• DOI: 10.1016/j.jsames.2018.06.018
• Publication Date: 2018-06-28T15:28:34Z
• Authors: H. Bruno; J. Almeida; M. Heilbron; M. Salomão; L. Cury
• Keywords: 15. Life on land; 01 natural sciences; 0105 earth and related environmental sciences

Abstract The amalgamation of tectonic blocks during the Brasiliano/Pan-African orogeny has been the main subject of study of several works in recent years. From the integration of a diversity of data, including the geophysical potential data and a review of the provenance of metasedimentary sequences based on detrital zircons and the geochemistry of granitoids, the tectono-metamorphic evolution of the Northern segment of the Dom Feliciano belt is addressed. Results reinforce the similarities between the Brusque and Paranagua terranes and the Itajai-Perimbo Shear Zone as a major tectonic boundary. The kinematic model envisaged highlights the control of basement blocks in the present tectonic geometry of the orogenic belt. In this new model, modern South American coordinates are adopted as the reference frame, with the Curitiba terrane moving towards SSE and the Angola Craton towards NNW, with the Luis Alves terrane trapped in between. This kinematic model is corroborated by aeromagnetic and gravimetric data that highlighted the importance of the Itajai-Perimbo Shear Zone as a major tectonic boundary in the northern segment of the belt, characterized as a suture zone separating two tectonic blocks with a distinct history of geodynamic evolution. The oblique collision between the blocks resulted on the development of a dextral transpression along Itajai-Perimbo shear zone that is the main boundary between Luis Alves and Brusque terranes, the sinistral strike-slip Palmital Shear Zone that separates the Luis Alves and the Paranagua terranes and by a frontal thrust, represented by the Icapara- Negra Shear Zone that bounds the already amalgamated block of the Luis Alves and Curitiba terranes from the outer Paranagua terrane.