Aplicação de dados SRTM (Shuttle Radar Topography Mission) no estado do controle neotectônico da rede de drenagem e microbacias hidrográficas, na região de Urucu e Adjacências (AM)

Abstract

Geologic studies of the Neogene of the Amazon have shown significant evidence of recent tectonic processes, analysis, particularly from the structural control of the valleys and rivers. Given this context, the objective of this study referred to the research area of neotectonic Urucu and Surroundings (AM) through the structural analysis of drainage systems and topography from digital products, namely, images SRTM (Shuttle Radar Topography Mission). The understanding of the latest tectonic structure, the region of Urucu (AM), is fundamental in defining the current landscape geometry. Thus, this study was crucial for the recognition of reactivated structures (NE-SW, NNE-SSW, NW-SE) and neoformed (EW and ENE-WSW), which certainly influence the control of landscape drainage and relief during the Neogene to the present. The initial analysis of alignments of drainage and relief from SRTM images allowed the interpretation of two main sets of discontinuities. The first set includes the structures oriented EW and ENEWSW, which are associated guidelines NE-SW and NNE-SSW. The second set brings together the structures positioned to NW-SE and NNW and SSE. The first set relates to a structure with probable transcurrent movement, where NE-SW orientations represent "splays" who are willing to make up a structural sigmoidal-like duplexes directional. Structural assemblies oriented NNESSW seem to represent a second pulse within that directional movement / transpressive. The second set is represented by discontinuities NNW-SSE. These guide the geometry and impose asymmetries in the drainage network, which are compatible with the definition of "fronts" and reverse in relief. The landscape seen resembles those developed drives dip-slip "normal. A second pulse of drive geometry of normal fault oriented NW-SE limits floodplains and causes the dam's natural river system, providing displacement of fluvial channels. Latter pulse probably occurred during the Holocene. Also, based on geophysical data type field of Total Reduced IGRF (International Geomagnetic Reference Field) can be seen that there is a strong correlation between neotectonic structures and magnetic anomalies, indicating that the structures are associated with the newly formed structures EW and ENE-WSW and structures of reactivation of ancient structures are presented with directions NE-SW, NNE-SSW, NW-SE.