Evidências de movimentos neotectônicos no interflúvio Baixo Rio Xingu Baixo Rio Tocantins, Nor-Nordeste do Estado do Pará, com base em imagens SRTM e PALSAR

The mouth of the Amazon River and the Lower Tocantins River-Lower Xingu River divide were the scene of intense neotectonic activity (Miocene-Holocene), which are here highlighted based on remote sensing images of the microwave bands: SRTM and PALSAR. The images in the SRTM highlight the topography and the ones in the PALSAR highlight the identification of paleochannels in plane lands in the alluvial fan. The presence of paleochannels of various ages, the tilting and the separation of the island of Marajó from the continent, with reflexes in the captures of the rivers Tocantins and High Anapu – which were part of the drainage basin of the Amazon Basin – as well as the formation of a large alluvial fan at the mouth of the River Tocantins, attest the neotectonic activities in the studied region. The following radargeologic units were identified: igneous-metamorphic basement from the Paleoproterozoic; volcano-sedimentary sequence from the Neoproterozoic; siliciclastic sediments with dominance of psamites from the Cretaceous; lateritic paleogenic covers; lateritic neogenic covers, alluvial fans from the Plio-Pleistocene; pleistocenic terraces and holocenic alluvions. Systems of dextral transtensional faults with about E-W orientation and normal faults to N-S orientation were the main movement acting in the region. In terms of cinematics, the 1 (horizontal) following E-W and the 2 (vertical) . While the 3 (horizontal) are disposed according the N-S orientation. The metallogenetic implications consist that the laterites are better developed with bauxite and kaolin to the North and the South of the studied area , where altitudes are more higher.