Navegando por Autor "MATTA, Milton Antonio da Silva"

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Evolução geológica da região de Tucuruí - Pará
(Universidade Federal do Pará, 1982-05-27) MATTA, Milton Antonio da Silva; HASUI, Yociteru; http://lattes.cnpq.br/3392176511494801
The northern part of the Araguaia Belt is exposed in the Tucuruí region and their stratigraphic, structural, metamorphic and magmatic features had been studied aiming at contributing for the understanding of the geological evolution of the area. The oldest stratigraphic unit of the area is represented by the Xingu Complex, composed by gneisses and granitos and subordinated schists and anphibolites. These rocks show evidence of a polycyclic metamorphic and structural history. Over this unit, during the niddle Proterozoic, the Tucuruí Group was developed. The bottom of this unit is composed by a sequence of tholeiitic basal-tic flows which were hera enclosed in the Caripé Formation. The Morrote Formation, is made up of graywackes, and constitutes the upper part of the Tucurui Group. The geossinclinal evolution of the Araguaia Belt took place during the Uruaçuano Cycle. This geotectonic unit is represented in the studied area by the Couto Magalhães Formation (Tocantins Group) which comprises pelitic and psamitic metasediments. These rocks show a greenshist facies metamorphism and structures generated by two phases of deformation in conditions of lower structures level. After the metamorphism of the Araguaia Belt, the Couto Magalhães Formation acted as the place of mafic and ultramafic intrusion and, lately, the Tucuruí Fault thrusted the metamorphic rocks of the Tocantins Group over the Tucuruí Group lithotypes. This faulting, besides generating a. series of structural features in the both groups as well as in the later migmatites, has also induced a dynamic metamorphic event into the rocks under green-schist facies conditions. Through the statistic treatment of structural data from the denso fault population which cuts the area, it was possible to deduce the shertening and the eterlding directiors related to the progressivo deformation induced by the thrust faulting had acted from E to W. Post-faulting mafic dykes represent the last magmatic event related to the Mesozoic Era. During the Cenozoic the area was a place of Tertiary sedimentation (Barreiras Formation), with sand, clays and conglomeratic levels. A final reactivation was responsible for the fracturing and faulting showed by the Barreiras Formation lithotypes Quatérnaty deposits mostly alluvial sediments, are the final units of the area.
Acesso aberto (Open Access)
Fundamentos hidrogeológicos para gestão integrada dos recursos hídricos da região de Belém/Ananindeua - Pará, Brasil
(Universidade Federal do Pará, 2002-12-20) MATTA, Milton Antonio da Silva; REBOUÇAS, Aldo da Cunha; http://lattes.cnpq.br/7322958772719317
The main goal of this study is to present the result of an investigation carried out in the region of Belém and Ananindeua. State of Pará — Brazil. The study comprised mainly hydrogeological aspects, together with hydrochemical, geological and socioeconomic data, in order to make it possible to determine the conditions to the wise use of groundwater. This work will also contribute to the municipal and state planners with a set of technical, legal and socioeconomic, data to be used toward the water resource management in the studied area. The activities and the methods applied permitted to achieve significant results which include the characterization of the physical environment, with geomorphology, soil and climate aspects, superficial water characteristics, hydrogeological systems properties, geometrical aspects of the main aquifer units. characteristics of the groundwater flow, hydrogeochemical and bacteriological qualities of the groundwater , the estimation of the groundwater reserves and an insight on its vulnerability. Ali those technical aspects were analyzed together with the legislation framework, from the federal to the municipal scales. in order to make it possible to define the fundamental aspects to the groundwater use and protection planning and its role in the general water management practices in the studied area. The main products include a data base, inserted in a Geographic Information System (GIS), based in the SPRING 3.5.1 program, a set of thematic maps (geological, geomorphologic, hydrogeological, soils, etc.), and a set of tables and graphics showing the physical, chemical and bacteriological aspects of groundwater quality. Technical, social and political propositions were made, including hidroambiental education, institutional projects against poverty, increase of the law enforcement to protect the water resources, water save actions by the government, and joint projects toward water management. The main conclusions of the study permit to demonstrate that the main goals have been achieved, with a significant contributions to the Hydrogeology of the Belém and Ananindeua area and to the future projects involved water resources management.