SISTEMAS DE DIACLASES E INFLUêNCIA TECT NICA DA BORDA SUDESTE DA BACIA SEDIMENTAR DO PARNAíBA: PARQUE NACIONAL SERRA DA CAPIVARA, BRASIL - DOI: 10.7154/RDG.2012.0023.0011

O Parque Nacional Serra da Capivara com suas características geomorfológicas peculiares faz deste sítio um importante foco de estudo. Suas características geomorfológicas s o herdadas do resultado de um tipo de clima muito mais úmido com o atual, além das atividades tect nicas cujo entendimento pormenorizado ainda se encontra distante, pois gerou uma série de esfor os nas rochas sedimentares da Bacia do Parnaíba, o que resultou num intrigado sistema de diaclases de dire es variadas e de importancia relevante na evolu o e configura o atual do relevo. A identifica o das diaclases abre um novo caminho para o entendimento do relevo ruiniforme, muito comum nas bordas sul e sudeste do parque, que é gerado pela tendência de infiltra o das águas pluviais nessas diaclases, o que acentua o processo erosivo e esculpe formas peculiares. O Fator tect nico, muitas vezes renegado ou subestimado na configura o do relevo brasileiro, come a a aflorar de maneira conspícua na comunidade geomorfológica brasileira e muitas das explica es sobre o modelado produzidas entre os anos de 1960 a 1990 come am a ser revistos sobre essa nova óptica. FRACTURES SYSTEMS AND TECTONIC INFLUENCE OF THE SOUTHEAST EDGE OF PARNAíBA SEDIMENTARY BASIN: SERRA DA CAPIVARA NATIONAL PARK, BRAZIL Abstract: The Serra da Capivara National Park with their peculiar geomorphological characteristics also make it an important focus of studies, once the refief of the area was the scene of activities done by the pre-historical populations who lived there and who registered the most varied daily activities through rupestral paintings. The geomorphological characteristics of the park are inherited from both a kind of much more humid climate, which lasted until approximately 10 thousand years ago, and from the tectonic activities, whose detailed explanation is far from being understood, for they generated a series of efforts in the sedimentary rocks of the Basin of Parnaíba that resulted in an intriguing system of fractures in various directions, often truncated, of relevant importance for the evolution and current configuration of the relief. The easy visualization of these fractures, through satellite images, aerial photographs, and field work, open a new path for understanding the ruiniform relief, which are common on the southern and south-eastern edges of the park and generated by the tendency of rainwater which percolated these fractures, causing accentuated processes of erosion and sculpting peculiar forms of incredible beauty that fascinate tourists and researchers from various parts of Brazil a