Dissertações em Geologia e Geoquímica (Mestrado) - PPGG/IG

URI Permanente para esta coleçãohttps://repositorio.ufpa.br/handle/2011/2604

O Mestrado Acadêmico pertence ao Programa de Pós-Graduação em Geologia e Geoquímica (PPGG) do Instituto de Geociências (IG) da Universidade Federal do Pará (UFPA).

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Aspectos lito-estruturais das minas de ferro N4E e manganês do azul, Serra dos Carajás-Pará
(Universidade Federal do Pará, 1991-08-06) MARÇAL, Mônica dos Santos; COSTA, João Batista Sena; http://lattes.cnpq.br/0141806217745286
The areas of iron (N4E) and manganese (Azul) mines in the Serra dos Carajás region were investigated with emphasis on structural geology, aiming to define the geometric arrangement of the various ore bodies and the kinematic framework, as well as their relationships with the regional structuring. The iron mine (N4E) is subdivided into two segments called Aba Leste and Aba Sul. The lithotypes occurring in this area are represented by friable itabitite (soft hematite HM, hard hematite HD), metajaspilite, metavolcanic rocks and canga. . Most of the rock units are distributed in the form of lenses and discontinuous and wedged bands, with a general orientation N-S on the East Rim and E-W on the South Rim, drawing a “J” with concavity facing northwest. The analysis of the structural elements present in the rocks of the N4E mine, in line with the information available for the Serra Norte region, allowed the characterization of three sets of main structures: the oldest set comprises the mylonitic foliation, the shear zones with oblique riding character, stretch lineation and associated folds; the second set refers to the NW-SE, E-W and N-S ductile transcurrent shear zones that cut and limit the body of N4; the last set corresponds to the folds and crenulations present throughout the entire ore body. These sets of structures are interpreted in the context of a single deformational event. The lithotypes that make up the manganese mine (Blue) are classified into three types: Protomines, Surface Deposits and Subsurface Deposits. Mining is currently being carried out in the central part of the deposit, between the LT00 and LT800E lines, where the ores related to surface and subsurface deposits were identified. The first includes pisolites (PIS), blocks (BL), platelets (PLT) and manganese breccias (BLM), and the second encompasses manganeseiferous mudstones (PM), granulated manganese material (MMG) and massive manganese material (MMM). The various types of manganese ore are wavy, defining synformal and antiformal structures oriented in the E-W direction and associated with strongly inclined thrusts to the north. The N4E and Azul mines are located on the northern edge and in the central-north region of the divergent macrostructure of Serra dos Carajás, respectively. Such a regional geometric arrangement is interpreted as a positive flower structure associated with an E-W sinistral binary. In this sense, the lithostructural units of the two studied areas must be understood as fractions of an inverted transcurrent volcano-sedimentary basin.
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Caracterização morfoestrutural e morfotectônica de áreas transpressivas: Serra dos Carajás e Serra do Tiracambú
(Universidade Federal do Pará, 1999-12-11) ESPÍRITO SANTO, Cláudia Vilhena do; COSTA, João Batista Sena; http://lattes.cnpq.br/0141806217745286
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O Cinturão Araguaia na região de Xambioá (TO) - São Geraldo do Araguaia: geometria, cinemática e aspectos litológicos
(Universidade Federal do Pará, 1993-09-22) SANTOS, Raimundo Oliver Brasil dos; COSTA, João Batista Sena; http://lattes.cnpq.br/0141806217745286
The northern segment of the Araguaia belt, near the cities of Xambioá and São Geraldo do Araguaia, consists mainly of supracrustal rocks from the Estrondo Group, in addition to gneisses from the Colméia Complex, exposed in the cores of the Lontra and Xambioá structures, exposed in the cores of the structures from Lontra and Xambioá, and from rocks from the Pequizeiro Group, which make up a narrow strip at the western end of the area. Considering the geometry and nature of the larger structures as well as the complexity of the structural framework, the area was divided into 5 (five) sectors. According to this picture, it was deduced that the macro geometric arrangement corresponds to an imbricated system of ductile thrusts, with rare "nappe"-type features standing out. thrusts; holomorphic folds related to late thrusts, or the transpression between transcurrent systems; and transcurrent shear zones, interpreted as lateral ramps. At the mesoscopic level, the structures are represented by the mylonitic foliation, the stretch lineation, folds of different styles and the On the other hand, thin lamina analysis revealed microstructures such as: porphyroclasts and asymmetric porphyroblasts with pressure shadows; quartz ribbons; S-C arrangements, tectonic twins in feldspar crystals; pisciform features; quartz-feldspathic aggregates in the form of lenses, microbanding, and recovery features. chthonic, four main movements were characterized in the progression of shear deformation: the first is related to the intense imbrication of rocky bodies resulting from the propagation of ductile thrusts, which must have been accompanied by the individualization of the lateral slopes; the second is associated with the uplift of splinters from the basement, imposing kilometric folds in the initial arrangements, due to a second generation of thrusts that did not affect the uppermost packages. At this point, it is assumed that there was significant movement along the side ramps; the third refers to the rotation of the megafolds, preferably in the central part of the area, due to the intensification of movements on the side ramps; and the fourth corresponds to the imbrication that was superimposed on the geometric arrangement created by these lateral ramps. Tectonic evolution, as understood here, developed according to the oblique collision process of continental masses, with preferential transport of rock units from SE to NW. Finally, a brittle regime is recorded through fault and fracture systems that are associated with Paleozoic and Mesozoic extensional events and, in part, with the neotectonic framework.
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Considerações lito-estruturais sobre o duplex transpessivo Serra Pelada
(Universidade Federal do Pará, 1992-07-18) OULD LAB, Khalifa; COSTA, João Batista Sena; http://lattes.cnpq.br/0141806217745286
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Evolução estrutural da Bacia do Amazonas e sua relação com o embasamento
(Universidade Federal do Pará, 1991-02-19) WANDERLEY FILHO, Joaquim Ribeiro; COSTA, João Batista Sena; http://lattes.cnpq.br/0141806217745286
This dissertation presents some aspects concer- ning the structural evolution of the Amazon basin and discusses the role of the Pre-Cambrian structures in the development of its architeture. The Pre-Cambrian record comprises strutures re- lated to two main thermal-tectonic events. The oldest one, Archean age, is responsible for the installation of granitic- greenstone terrains, and also the formation of shear belts composed of high grade metamorphic rocks. This event controlled the formation of the basic structural lineaments, trending Nw- SE, NE-SW and E-W. The second event, in the eastern Amazon re- gion, caused the development of NW-SE and WNW-ESE normal faults and NE-SW transfer faults related to an extensional NE-SW proterozoic axis giving rise to the formation of several basins of which, Cachimbo Graben is the most remarkable one. The structural evolution of the Amazon basin throug Phanerozoic time is strongly related to the geometry of the Pre-Cambrian structures. The installation of the Amazon basin is related to cyclic opening and closing of the Iapetus ocean during Paleozoic time. During this cycle, ancient weakness zones tren- ding NE-SW and NW-SE were reactivated as normal and transfer faults respectively. The movements associated to the transfer faults compartmentalized the basin into four distinct structural blocks, of which the compartmental zone of Purus (Purus Ar- ch) isa special example. The Purus arch separates the Amazon basin to the East from Western Solimões basin. Its origin is related to reactivation of normal faults of the Cachimbo Graben. The fragmentation of the Gondwana megacontinent, during mesozoic time, is witnessed in the Amazon basin by the following features: a) NE-SW and NNE-SSW normal faults; b) Nw- SE transfer faults; c) ENE-WSW wrench faults and d) igneous and sedimentary infill. During Cenozoic time, the Amazon basin and adjacent zones suffered effects of stress that generated essencially dextral whrench faults.
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Evolução paleogeográfica, durante o cenozóico, da região de Bragança, NE do estado do Pará
(Universidade Federal do Pará, 2002-02-28) ALMEIDA, João Revelino Caldas de; BORGES, Mauricio da Silva; http://lattes.cnpq.br/1580207189205228; COSTA, João Batista Sena; http://lattes.cnpq.br/0141806217745286
The main morphologic features of northeastemn Para State are strongiy related to middle Cenozoic extensional tectonics which is responsible by the Gondwana break up resulting in the formation of the Equatorial Atlantic Ocean and of the passive margin. The area is included in the Bragança-Viseu Basin, which evolved from the extensional tectonics incidence on the northeastem of the Para State since the Upper Jurassic. During the Miocene this area underwent transtensional tectonics that generated NW-SE normal faults and E-W and NE-SW dextral strike-slip faults. This tectonic event formed large subsided areas and corridors that facilitated transgression towards the continent since 150 km from the present coastline. This transgression originated the carbonatic sequence included in the Pirabas Formation, deposited in areas with drainage systems typical of subsided regions. Some areas remained emerged during the transgression. In the Bragança-Viseu Basin the sediments of Pirabas Formation are scarce, which suggest presence of a structural high blocking the transgression of the “Pirabas Sea”. The occurrence of limestone towards the south of Bragança suggest a cost line characterized by bay heads and promontories facing northwest. On the basis of geophysics interpretation, it was demonstrated in the Bragantina region the absence limestone towards the main depocenter of the Bragança-Viseu Basin. Therefore in this area, there are only occurrence of Precambrian rocks overlaid by Quaternary sediments (debris flows) included in the Post-Barreiras sequence.. The landscape has not change since Miocene - Pliocene, as can be demonstrated by the colinas relief. The geologic data suggest that the landscape evolution is controlled by structures related to the transtensional event.
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Geologia estrutural da Bacia do Marajó
(Universidade Federal do Pará, 1994-12-01) CAHUANA VILLEGAS, Javier Marcelo; COSTA, João Batista Sena; http://lattes.cnpq.br/0141806217745286
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Geologia estrutural do Cinturão Araguaia e ao longo da seção compreendida entre as cidades de Marabá e Apinagés
(Universidade Federal do Pará, 1994-08-05) LIMA, Jairo Bezerra de; COSTA, João Batista Sena; http://lattes.cnpq.br/0141806217745286
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Investigações tectônicas no embasamento da sub-bacia do Jandiatuba (bacia do Solimões)
(Universidade Federal do Pará, 1995-08-10) VEGA SACASA, Roberto de Jesus; COSTA, João Batista Sena; http://lattes.cnpq.br/0141806217745286
Through this work, we sought to understand the structural framework of the continental crust of the western portion of the Solimões Basin called Jandiatuba Sub-basin. With this approach, the nature of the basement and intrabasement structural systems of the basin was characterized based on the geometry and depth of the reflectors. The analysis of conventional seismic sections, used in oil prospecting, and of three versions of a deep seismic profile, with records from 15 to 19 seconds (double time), provided the definition of the following structural elements. (a) inverse faults in the Jandiatuba sub-basin sedimentary package; (b) fault zones that dip following a pattern in the form of ramps, which may be related to shear zones or back-thrusts, especially in the upper crust; (c) detachments that permeate the crust and project into the crust-mantle interface; (d) imbrications in the middle and lower intervals of the ductile crust expressed through a strongly anastomotic signature; (e) seismic “transparency” of the brittle upper crust evidenced by the absence of reflectors, in addition to “transparent” lenses in the deeper crustal levels; (f) the discontinuity of the Moho characterized by several anastomotic beams of reflectors, the differentiation of reflectivity and the decrease in amplitude and frequency in the range of 38 to 45 km. The analysis of the collection of results of the different programs existing on the various continents on deep reflection seismic (COCORP, BIRPS, DEKORP and ECORS), helped in the interpretation of the set of reflectors and was fundamental for the comparison and correlation between the different seismic signatures. The complexity of the seismic signatures of this crustal segment of Amazonia was mainly related to the geometry of structural systems of thrust belts and transcurrents, as well as extensional basins. In other words, seismic arrangements resulting from the action of compressive, directional and extensional regimes were identified. The defined structural framework was discussed through three models that consider compression and imbrication in the Precambrian, stretching in the early Paleozoic and transpression in the Jurassic. Therefore, the Jandiatuba sub-basin region corresponds to a crustal segment that experienced at least three main tectonic movements during its geotectonic evolution.
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Neotectônica e morfogênese da região de Carolina (Ma, To), bacia do Paranaíba
(Universidade Federal do Pará, 1996-10-05) BEZERRA, Pedro Edson Leal; COSTA, João Batista Sena; http://lattes.cnpq.br/0141806217745286
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Neotectônica na bacia de São Luís
(Universidade Federal do Pará, 1996-02-12) FERREIRA JÚNIOR, Carlos Roberto Paranhos; COSTA, João Batista Sena; http://lattes.cnpq.br/0141806217745286
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Organização lito-estrutural do duplex Salobo-Mirim Serra dos Carajás
(Universidade Federal do Pará, 1990-06-06) SIQUEIRA, José Batista; COSTA, João Batista Sena; http://lattes.cnpq.br/0141806217745286
The Salobo Group embodies a sequence of volcanosedimentary rocks, which overlain a sialic basement, and is linked to the evolution of the Cinzento Transcurrent System, situated immediately to the north of the transcurrent system which provided the estabelishment of the Grão-Pará Group. The macrostructure is formed by two major shear zones which join at the west and east end parts of the studied area, defining a WNW-ESE eliptcal structure. This structure, which is interpreted as an extensional duplex, comprises, internally, minor shear zones that converge to the main zones. NW-SE, NNE-SSW and NE-SW strike-slipe zones modify the major geometric pattern. The duplex lithologies underwent metamorphism of the amphibolite facies during regional transpression, followed by expressive hidrotermalism and greenschist facies transformation trought the progress of the deformation. Significant mineralizations of bornite, chalcocite and in some cases chalcopirite, with molibdenite, gold and silver, are mainly hosted by lenses of iron formations, besides magnetite. These sulphides are distrubuted as inclusions in the grains of silicate gangue minerals and oxides or between them, as well as along the ductile and ductile-ruptile features, such as milonitic S-C foliations and R, R', p and y=D fractures, showing the manifold origin of such mineralizing fluids. Two kinematics models can be visualized to explain the main litho-structural units: sinistral stike-slip system involving transtension, followed by transpression and then transtension; and crotonic reworking related to transtension regime.
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Paleografia e evolução da paisagem do nordeste do estado do Pará e noroeste do Maranhão: cretáceo ao holoceno
(Universidade Federal do Pará, 2002-02-28) SOARES JUNIOR, Adilson Viana; COSTA, João Batista Sena; http://lattes.cnpq.br/0141806217745286
This research presents some aspects of the tectonics and paeleogeographic evolution of northeastem region of Pará State and northwestem region of Maranhão State in the northem Brazil, based on the integration of structural, tectonic, stratigraphic, sedimentological and paeleontological data. The Marajó basin is elongated in a NW-SE direction and includes a sedimentary sequence deposited ffom Upper Cretaceous to Upper Tertiary. The geometry of the Marajó Basin is characterised by NW-SE normal faults in the northwest-southeast direction and NE-SW and ENE-WSW strike-slip faults, which define the boundaries ofthe Mexiana, Limoeiro, Cametá and Mocajuba sub-basins. The Gurupi Graben System encompasses the Bragança-Viseu, São Luís and Ilha Nova basins, with Cretaceous and Tertiary sedimentary filling. The Bragança-Viseu Basin is formed by two assymmetric grabens - the Caeté depocenter (close to the northem border) and the Piriá depocenter, close to the southem limit - in a NW-SE direction, separated by a transcurrent fault. The São Luís Basin comprises three sub-basins: Maracaçumé, in the northwest, Bacuri, in the northeast, and Bequimão, toward the southeast. The Ilha Nova basin is divided into two halfgrabens separated by a transcurrent fault. The westem half-graben presents antithetic faults in the southem and northem borders, while these faults ocurr only in its northem extreme ofthe eastem halfgraben. The Grajaú Basin is an extensional feature of the Cretaceous, generated by normal fault propagation towards the continent interior, during the opening ofthe Equatorial Atlantic, and by partial reactivation of the Paleozoic structures of the Pamaíba basin. The stratigraphy is composed ofthe Grajaú, Codó and Itapecurú formations, controled by N-S planar normal faults, diping to the west, and linked through NE-SW transcurrent faults. The Gurupá Are strikes NW-SE, correspond to the boundary ofthe Amazon Basin, and defines the shoulder ofthe Marajó basin, closely associated with listric faults. Northem Marajó encompasses the region between the northeastem shoulder of the Marajó Basin and the Pará/Ilha de Santana Platform, and is characterised by neotectonic structures represented by NE-SW transcurrent faults, as those that control the mouth of the Tocantins river towards the northeast. 4 The Tocantins Are is a positive feature that bounds the Marajó and Grajaú basins, and corresponds to a transpressive region. The Gurupi Are is a positive feature that limits the Bragança-Viseu and São Luís basins, running in a NNE-SSW direction, and worked as an area wich accomodated high strain during the Cretaceous. The Ferrer-Urbano Santos Are is an E-W positive feature that limits the São Luís and Grajaú basins formed during the Cretaceous, with an axis of uplifting that migrated southwards through the time. The partial collapse ofthis are evolved to the São Luís Basin. The Tiracambú Hills derived from Grajaú Basin inversion, since the Paleocene, wich resulted in the propagation ofE-W transcurrent dextral systems and was followed by the tectonic calm that originated the mature lateritic profile. The Estrondo Hills is related to N-W normal faults, and is interpreted as derived by reactivation of older struetures during the Cretaceous-Upper Tertiary extensional event, controlling the courses ofthe Araguaia and Tocantins rivers
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Tectônica cenozóica e movimentação salífera na Bacia do Amazonas e suas relações com a geodinâmica nas placas da América do Sul, Caribe, Cocos e Nazca
(Universidade Federal do Pará, 2002-09-13) COSTA, Antônio Roberto Almeida; COSTA, João Batista Sena; http://lattes.cnpq.br/0141806217745286
This research, based on seismic section interpretations, deals with the tectonic events and salt movement (halotectonic) that took place in the Amazonas Basin during the Cenozoic. The main structures have been compared with the tectonic signatures of the Solimões, Acre and Tacutu basins in order to understand the kinematic events that affected the sedimentary filling of those basins. The Amazonas, Solimões, Acre and Tacutu basins and some parts of the South American Plate underwent intraplate deformational events during the Cenozoic. From tectonic data of the Northern Andes and Caribbean area, including the northern South American Plate, and available kinematic models, it could be reached the integration of the stress field that originated the major tectonic elements that affected the sedimentary basins of the Amazon region, especially the western part of the Amazonas Basin. From Upper Miocene to Holocene the Northern Andes reached its current configuration. The Upper Miocene corresponds to the beginning of the uplift of the northeastern Andes and represents the most dynamic tectonic phase of the Miocene. The main landforms of the Andean chain developed during the Miocene and few changes have occurred since then. The complex structural pattern of the northern South America is related to the oblique compressive stress in the plate margin that imposed deformation on the convergent systems of the Cretaceous and Paleocene, when South America has been pushed against the Caribbean and Nazca plates. The intraplate stress field data of the northern South America are still few to support the best characterization of the regional pattern of this long and vast area, which is marked by a high diversity and complex tectonic setting. The intraplate stress field seems to be the result of the action of local and regional forces in the lithosphere. Local stress pattern could be due to the structural heterogeneities, the increase and reduction of crustal load and the thermal anomalies from astenosphere. The regional forces are more uniform and directly related to the plates driving forces, such as: the force due to the spreading of the ocean floor (ridge-push); negative fluctuation of the subducted plate and forces of viscous shearing in the lithosphere-astenosphere boundary. The Juruá tectonic event was the most important mesozoic deformation that affected the Paleozoic Solimões and Amazonas Basins. The transpressive structures generated during this event are those revealed as petroleum traps, mainly in the Solimões Basin. From seismic interpretation of the Amazonas basin, it was demonstrated important structural style variation from region to region. Some areas show weak deformation while others are characterized by complex structures. On base of this criteria, the basin was divided into three structural domains, identified as North, South and Central domains and comprising 8 (eight) structural sectors. The North Domain includes the following sectors: Negro-Trombetas River and Curuá River; the South Domain comprises Canumã River, Mamuru River and Cupari River sectors; and the Central Domain includes Madeira River, Abacaxis-Tapajós River and Jurupari River sectors. Two tectonic events were characterized from seismic interpretations of the Amazonas Basin. The first was characterized only in the Manaus Platform area. The second is probably of Pliocene in age and it is characterized by folds and faulted blocks related to the transpressive system that affects post-Paleozoic sequences. The largest diversity and structural complexity were identified along the Abacaxis-Tapajós River sector, between the Central Domain and the boundaries of the North and South Domains. It is also in this area that occur the most important halotectonic features, as the salt pillows. The development of these features is mainly controlled by Cenozoic strike-slip tectonic events that caused the reactivation of ancient ductile zones and originated faults that cut the Amazonas Basin in the NE-SW and NW-SE directions; the largest thickness of the halite layers that occur in this region; the gravitational instability due to the differential load caused by diabase sills; and the steep dips of the layers. The halotectonic could have controlled the development of some relief features and part of the drainage systems of the Amazonas basin. The irregular and complex folds seen in the evaporitic sequence of the Nova Olinda Formation resulted from the high plastic behavior and tectonic mobility of the salt layers. Frequently the seismic layers under the sequence that contains halite are undeformed. But once deformed, they show different structural styles from those of the interval that contains halite. The structural styles in the platform areas (Manaus e Abacaxis-Mamuru) show geometric characteristics (transpressives and transtensives) which are very simple when compared with the more complex structures that occur in the area of the Central Domain that had been originated under a more plastic deformational regime due to the largest halite volume. The strike-slip faults usually originate complex structural effects in the geologic section of some basins which result in difficulty for the interpretation of seismic data. The complexities are related to the nature of the mechanism of the strike-slip faulting. The flow of salt along the strike-slip zones follows offsets upwards resulting in irregular folds when the salt thickness increases. Therefore, when the sequence that contains the salt layers is submitted to strike slip faulting, the geometry of the structures becomes normally complex. This could be explained due to the plastic behavior of the salt that acts as a layer where the strike-slip stresses are attenuated, hindering the faulting propagation in the upper sequences. In the Amazonas Basin is clear this relationship between the halotectonic features and Cenozoic strike-slip faulting. The seismic interpretations in this research are not enough to identify the structures related to the Quaternary events, but the geologic data and the information from focal solution mechanism of earthquakes and breakouts indicate that the Amazon Basin have remained active in the Quaternary time. Therefore, it is possible that halotecnonics have occurred during the Quaternary.

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