Major shear zones of southern Brazil and Uruguay: escape tectonics in the eastern border of Rio de La plata and Paranapanema cratons during the Western Gondwana amalgamation

Abstract

The Mantiqueira Province represents a series of supracrustal segments of the South-American counterpart formed during the Gondwana Supercontinent agglutination. In this crustal domain, the process of escape tectonics played a conspicuous role, generating important NE-N-Strending lineaments. The oblique component of the motions of the colliding tectonic blocks defined the transpressional character of the main suture zones: Lancinha-Itariri, Cubatão-Arcádia-Areal, Serrinha-Rio Palmital in the Ribeira Belt and Sierra Ballena-Major Gercino in the Dom Feliciano Belt. The process as a whole lasted for ca. 60 Ma, since the initial collision phase until the lateral escape phase predominantly marked by dextral and subordinate sinistral transpressional shear zones. In the Dom Feliciano Belt, southern Brazil and Uruguay, transpressional event at 630-600 Ma is recognized and in the Ribeira Belt, despite less coevally, the transpressional event occurred between 590 and 560 Ma in its northerncentral portion and between ca. 625 and 595 Ma in its central-southern portion. The kinematics of several shear zones with simultaneous movement in opposite directions at their terminations is explained by the sinuosity of these lineaments in relation to a predominantly continuous westward compression.

(U‐Th)/He Thermochronology and Zircon Radiation Damage in the South American Passive Margin: Thermal Overprint of the Paraná LIP?

“…It is characterized by kilometer‐wide mylonite belts enveloping sin‐transcurrent granitic intrusions (Bitencourt & Kruhl, ; Oriolo et al, ; Passarelli et al, ). Together with its extension in southernmost Brazil and Uruguay, the Dorsal do Canguçu, and Sierra Ballena Shear Zones, respectively, it forms a lineament over 1,000 km‐long that has been interpreted as a former suture zone (Basei et al, ; Passarelli et al, ).…”

Lithologies, structure and basement-cover relationships in the schist belt of the Dom Feliciano Belt in Uruguay

“…Both domains seem to have the same bulk Neoproterozoic history, but the evidence is indisputable in the Ediacaran, which relates a common event of post-collisional transpressive and semi-brittle tectonic escape along several strike-slip shear zones (e.g., Soares & Rostirolla 1997, Passarelli et al 2011, Oyhantçabal et al 2011b, Oriolo et al 2016c.…”

Tectonic evolution of the Brusque Group, Dom Feliciano belt, Santa Catarina, Southern Brazil

“…Likewise, the DFB internal organization follows the major structure, with the three constituting segments separated by expressive fault zones. The contact between the Granitoid and the Schist belts is defined by the Major Gercino (Santa Catarina, BR) e Cordilheira (Rio Grande do Sul, BR) e Sierra Ballena (Uruguay) Shear Zone, which is considered a lithosphericscale lineament (Basei et al, 2008a,b;Passarelli et al, 2010Passarelli et al, , 2011. The contact between the Schist Belt and the Foreland Basins is also tectonic, well characterized in Santa Catarina by low-angle faults that place the Brusque Group metamorphites on the Itajaí Group sediments.…”