Tecttôniica póss--riifftte na Baciia Pottiiguar

The study of Brazilian sedimentary basins concentrates on their rift phase, whereas the Post-rift phase has been considered a tectonic quiescent period. The post-rift sequence of the Potiguar Basin, in the far northeastern Brazil, was once considered little deformed, however several studies have shown how that it was affected by major fault systems. The purpose of this thesis is to characterize the post-rift tectonic. The specific objectives are: to characterize the Neogene and Quaternary sedimentary units that outcrop of the Potiguar Basin; to show how the NW-SEtrending Afonso Bezerra Faults System deformed outcrop rocks in the Basin; to describe soft-sediment deformation in gravels of the Quaternary Alluvial Deposits from Açu River. Facies analyses, grain-size studies, luminescence dating, remote sensing, structural mapping, shallow geophysics (georadar), paleostress and petrography were carried out. The structural mapping and the georadar sections indicated that the Carnaubais and Afonso Bezerra fault systems formed fractures, silicified and non-silicified faults or deformation bands, affecting mainly the Açu, Jandaíra and Barreiras formations. The petrographic data indicate that the strong silicification resulted in a sealant character of the faults. Paleostress analysis indicates that two stress fields affected the Basin: the first presented N-S-trending compression, occurred from the Neocretaceous to the Miocene; the second stress field presents E-W-trending compression, acts from the Miocene to the present. It was verified once the Afonso Bezerra System Faults was reactivated in periods post-Campanian and affects all post-rift lithostratigraphic units of Potiguar Basin, including Quaternary sedimentary covers. The study about soft-sediment deformation structures indicates that they are similar in morphology and size to modern examples of seismically-induced deformation strutures in coarse sediments. TL and OSL ages indicate that sediment deposition and associated soft-sediment deformation occurred at least six times from ~352 Ka to ~9 Ka. Finally these studies demonstrate how recent is tectonics in the Basin Potiguar

Divulgação científica para empoderamento institucional: o discurso da revista Darcy e a midiatização da academia

Science has remained in hegemonic position among the various forms of knowledge that enable us perceive our surroundings. After a growing movement of introversion of the scientific field, which enabled the empowerment of the academy, it is growing today the discussion about the need to spread knowledge of this area to society. Our study aims to observe the discourse of institutional science communication, taking into account the historical conditions that made possible the emergence of science as legitimate observation of nature and of man and also the credibility granted to the media. Therefore, we have as our study object the editorials of the Darcy magazine, for scientific and cultural journalism of the University of Brasilia. We focused on observing the discourse of knowledge sharing by the media, using the concepts of field, from Bourdieu’s work, and Agamben’s "profanation" together with notions from the organizational communication area. Also, the concepts of dispositive, discourse and knowledge-power used are based on the studies from the French school which associate them to the need of thinking power as a relation between what is and what is not said, having Michel Foucault as an important exponent of this area. The research, which uses as a method the Discourse Analysis, shows us a process of mutual validation of the scientific and journalistic discourses, which contribute to the strengthening of the institution itself as well as the scientific field, in texts which have as a backdrop the institutional image and reputation.