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ABSTRACT:The Piúma lineament, located in the Southern Espírito Santo State, Brazil, is one of the most prominent linear morphostructural features of the northern Mantiqueira Province. The lineament stands out in satellite images and topographic maps, extending for about 70 km in a N50°W direction, between the towns of Iconha and Conceição do Castelo (Espírito Santo). In order to investigate the nature and role played by the Piúma lineament in the tectonic evolution of the Mantiqueira Province and adjacent Campos Basin, we carried out a detailed structural analysis based on fieldwork, as well as geophysical data processing and interpretation. The results we obtained indicate that the Piúma lineament is a brittle shear zone characterized by N50W-trending and SW-dipping shear fractures, faults and joints. These structures record two distinct and incompatible motions, thereby recording the operation of two tectonic regimes: NNE-SSW extension and E-W transtension. Comparing our results with the literature on the Southeastern Brazilian Continental Margin, we conclude that the Piúma lineament more likely developed after the Ediacaran Brasiliano orogenic event in response to an NNE-SSW extension, experiencing later a reactivation as normal dextral to dextral transtensional zone, probably in connection with the South Atlantic rifting in the Lower Cretaceous. KEYWORDS:Remote sensing; Fractures; Paleostress analysis. RESUMO: O lineamento Piúma, situado na porção sul do estado do Espírito Santo, está entre as feições morfo-estruturais mais proeminentes da província Mantiqueira Setentrional. Constitui uma feição linear regional, bem marcada em imagens de sensoriamento remoto e mapas topográficos, com aproximadamente 70 km de comprimento e direção N50°W, entre as cidades de Iconha e Conceição do Castelo (Espírito Santo). Para investigar sua natureza e o papel que desempenha na evolução tectônica da Província Mantiqueira e da bacia de Campos

This paper presents the results of a new approach based on sandbox models to the understanding of the tectonic evolution of the Volta Redonda Basin, southeastern Brazil. Those models were designed to replicate the overlapping process of two of the four superimposed tectonic events identified in the Volta Redonda Basin: the first one, a rifting event with NW-SE extension direction that created the basin, and the subsequent E-W sinistral transcurrent tectonics. The boundary conditions for the models were set from the geological premises described in previous works, which resulted in the current conceptual geological models of the study area. The sandbox models were composed of alternating layers of colored sand, deposited on two pieces of acetate or cardboard sheets, which acted as pre-existing basement structures. Once completed, the models were cut and photographed to allow observation and interpretation of the resulting internal structures. Moreover, the interpretations maintain similarities with adopted conceptual models and permit conclusions about structures previously identified in other works. Finally, the consequent structural framework exposes the effects of structural reactivation and Basin geometry changes due to the superposition of deformational events and matches with the general structural aspects identified in field studies.