Aplicação de sísmica de alta resolução em ambiente estuarino amazônico, na investigação de estruturas neotectônicas

Abstract

Seismic methods of high resolutions have been intensely used on the mapping of the Quaternary, investigation of sedimentary processes, and others. The study area is located in the north region of the state of Pará, between the parallels 1° S and 2° S and the meridians 50.5° and 48.25°, the research being carried out in the submerged areas bordering the Marajó Island in its east and the southeast part, comprising the Bay of Marajó, the mouth of the Tocantins River and Pará River. The high resolution seismic employed in this region aims to tectonic investigation by using the data collected by the acoustic profiler SB-512I from Edgetech, and from these data to identify structural shapes, fractures, subsidence or elevations ruled by tectonism. From the analysis of the seismic data obtained in the study area, nine features were identified interpreted as tectonic occurrences. Due the specificities of equipment and geological characteristics of the region, possible areas of tectonic faults were not detected at great depths by the equipment used, however, they were found in areas where tectonic forces occurred with sufficient intensity to cause visible faults in the mapped pseudo-sections.