Cerro do Jarau is a conspicuous, circular morpho‐structural feature in Rio Grande do Sul State (Brazil), with a central elevated core in the otherwise flat “Pampas” terrain typical for the border regions between Brazil and Uruguay. The structure has a diameter of approximately 13.5 km. It is centered at 30o12′S and 56o32′W and was formed on basaltic flows of the Cretaceous Serra Geral Formation, which is part of the Paraná‐Etendeka Large Igneous Province (LIP), and in sandstones of the Botucatu and Guará formations. The structure was first spotted on aerial photographs in the 1960s. Ever since, its origin has been debated, sometimes in terms of an endogenous (igneous) origin, sometimes as the result of an exogenous (meteorite impact) event. In recent years, a number of studies have been conducted in order to investigate its nature and origin. Although the results have indicated a possible impact origin, no conclusive evidence could be produced. The interpretation of an impact origin was mostly based on the morphological characteristics of the structure; geophysical data; as well as the occurrence of different breccia types; extensive deformation/silicification of the rocks within the structure, in particular the sandstones; and also on the widespread occurrence of low‐pressure deformation features, including some planar fractures (PFs). A detailed optical microscopic analysis of samples collected during a number of field campaigns since 2007 resulted in the disclosure of a large number of quartz grains from sandstone and monomict arenite breccia from the central part of the structure with PFs and feather features (FFs), as well as a number of quartz grains exhibiting planar deformation features (PDFs). While most of these latter grains only carry a single set of PDFs, we have observed several with two sets, and one grain with three sets of PDFs. Consequently, we here propose Cerro do Jarau as the seventh confirmed impact structure in Brazil. Cerro do Jarau, together with Vargeão Dome (Santa Catalina state) and Vista Alegre (Paraná State), is one of very few impact structures on Earth formed in basaltic rocks.

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Crateras de impacto por meteorito são formações raras no planeta e de extrema importância para o conhecimento da evoluçãogeológica e biológica da Terra por se tratarem de eventos catastróficos que causaram extinções em massa e movimentaram camadasgeológicas. No Brasil sete crateras de impacto estão cientificamente comprovadas, dentre estas, quatro já classificadas como possíveissítios geológicos. A área objeto deste trabalho, o Cerro do Jarau, está localizada no sudoeste do Estado do Rio Grande do Sul, na divisa como Uruguai e insere-se no contexto geológico da Bacia do Paraná. Trata-se de uma feição semicircular de aproximadamente oito quilômetrosde diâmetro, com cristas elevadas, que se diferenciamgeomorfologicamente do Pampa Gaúcho. A região constitui-se num bom exemplo degeossítio no qual o patrimônio geológico pode associar-se ao patrimônio imaterial, entre eles valores culturais e arqueológicos, paraimpulsionar o turismo local com o apoio de estratégias de geoconservação e um plano geoturístico.Palavras chave: Crateras de Impacto, Geoconservação, Geoturismo, Patrimônio Geológico. ABSTRACT THE IMPACT CRATER OF CERRO DO JARAU, BRAZIL: A GEOTURISTIC APPROACH.Meteorite impact craters are rare formations onthe planet and of utmost importance for the understanding of the biological and geological evolution of the Earth because they areregisters of catastrophic events that caused mass extinctions and geological movements. In Brazil seven impact craters are scientificallyproven, among these four already classified as potential geological sites. The area object of this work, Cerro do Jarau, is located southwestof Rio Grande do Sul State, at the limit with Uruguay and is part of the geological context of the Paraná Basin. It is a semicircular featurewith approximately eight miles in diameter, with high ridges, which differ geomorphologicallyof the Pampa Gaúcho. The region constitutesa good example of geosite where geological heritage can join intangible heritage, including archaeological and cultural values, to boostlocal tourism with the support of geoconservation strategies and a geotourism plan.Keywords: Impact craters, geoconservation, geoturism, geological heritage.

O Projeto Geobike é uma iniciativa que objetiva aproveitar o potencial geológico de uma determinada região, utilizando a bicicleta como meio de transporte com o propósito de estimular e divulgar as Geociências tanto para os estudantes e profissionais da área acadêmica quanto para entusiastas das Ciências da Terra. A proposta inicial possui como área de estudo o município de Campinas, Estado de São Paulo, que, mesmo com a intensa ocupação urbana ainda dispõe de extensas áreas rurais com paisagens bem distintas, onde afloram rochas ígneas, metamórficas e sedimentares. Trata-se de cenário propício para a prática de trabalhos de campo alternativos, além da difusão do conhecimento geocientífico tanto em nível complementar acadêmico quanto voltado à extensão universitária, com a possibilidade de os afloramentos serem utilizados por alunos de escolas do ensino fundamental e médio. O Projeto Geobike pode, portanto, estar associado ao Geoturismo e à Geoeducação, englobando todos os níveis de escolaridade.

Terrestrial impact structures are geological and geomorphological features with particular importance to understand the history and evolution of the planet. Impact structures are scattered around the world but in many countries these features are under threat, essentially due to anthropic factors. Impact structures with higher scientific value should be considered as geological heritage and, consequently, be subjected to geoconservation strategies. In order to select the most important impact structures to be properly conserved and managed, this paper proposes a quantitative assessment method of the scientific value of these structures. The eight Brazilian impact structures were used to test this method that has the potential to be applied to any geological context in any country. The structures known as Araguainha Dome-MT and Serra da Cangalha-TO reached a higher scientific value, which justifies the need to develop geoconservation strategies and a proper management.