Programa de Pós-Graduação em Geologia e Geoquímica - PPGG/IG

URI Permanente desta comunidadehttps://repositorio.ufpa.br/handle/2011/2603

O Programa de Pós-Graduação em Geologia e Geoquímica (PPGG) do Instituto de Geociências (IG) da Universidade Federal do Pará (UFPA) surgiu em 1976 como uma necessidade de desmembramento do então já em pleno desenvolvimento Curso de Pós-Graduação em Ciências Geofísicas e Geológicas (CPGG), instalado ainda em 1973 nesta mesma Universidade. Foi o primeiro programa stricto sensu de Pós-Graduação (mestrado e doutorado) em Geociências em toda Amazônia Legal. Ao longo de sua existência, o PPGG tem pautado sua atuação na formação na qualificação de profissionais nos níveis de Mestrado e Doutorado, a base para formação de pesquisadores e profissionais de alto nível. Neste seu curto período de existência promoveu a formação de 499 mestres e 124 doutores, no total de 623 dissertações e teses.

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Agora exibindo 1 - 11 de 11

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Aspecto tectôno-sedimentares do fanerozóico do nordeste do estado do Pará e noroeste do Maranhão, Brasil
(Universidade Federal do Pará, 1992-09-16) IGREJA, Hailton Luiz Siqueira da; FARIA JUNIOR, Luis Ercílio do Carmo; http://lattes.cnpq.br/2860327600518536
A synthesis of the tectono-sedimentary evolution of the Phanerozoic at Northeastern Pará and Northwestern Maranhão is discussed with enphasis to the Bragança-Viseu and São Luis basins. This research is based on field observations, gravity (Bouguer Anomalies), magnetic, seismic, and borehole data interpretations. Five sedimentary sequences are defined: 1) Piriá-Camiranga (Cambrian-Ordovician to Silurian), 2) Lower Itapecuru (Lower Cretaceous), 3) Upper Itapecuru (Upper Cretaceous), 4) Pirabas-Barreiras (Oligocene-Mioceneto Pliocene) and 5) Pará (Quaternarg). The regional basement is an igneous-metamorphic assemblage which outcrops in two windows. The sedimentary and structural features of the Piriá-Camiranga sequence are consistent with a tectono-sedimentary model of coastal environment with fluvio-glacial influence related to a tilted blocks system induced by strike-slip motion. This sequence represents an evolutive stage coincident to the Eo-Hercynian paroxysm (Paleozoic) which ended with the closure of the Atlantic I (first geotectonic cycle of the Gondwana). The Lower and Upper Itapecuru, as well as the Pirabas-Barreiras and Pará sequences, are related to the Equatorial Atlantic opening during the Mesozoic and Cenozoic times. They are analysed by severa), authors which reached the interpretations refered to as Models of: Fracture Zones; Anti-clockwise rotation of Africa; Intumescence and fracturing; Clockwise rotation of the South America Nate; and Wrench Tectonics. These models were experimented for the studied area. The time and environments of the sedimentary processes are related to the rift and pos-rift phases of the equatorial coastal basins, but these models were not adequate to explain the structural features. A new model is proposed to explain the origin and development of the basins taking into account a regional NE-SW extension axis and formation of the Bragança-Viseu and São Luís basins with similar polarities. The tectono-sedimentary map for the Phanerozoic of the Northeastern Pará / Northwestern Maranhão enhances the compatibility of the depositional and tectonics systems with two periods of oceanic opening of the Northern Gondwana border.
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Estudo batimétrico sonográfico do estuário Guajará, Belém-Pa
(Universidade Federal do Pará, 1989-11-10) SILVEIRA, Odete Fátima Machado da; FARIA JUNIOR, Luis Ercílio do Carmo; http://lattes.cnpq.br/2860327600518536
The Guajará Estuary, surrounding the city of Belém, encompasses the homonymous Bay and the confluence of the Guamá and Guajará-Açú rivers. Distant about 120 kilometers from the Atlantic Ocean, it has been studied in recent years, mainly regarding its hydrodynamic, physical and chemical parameters, in addition to the qualitative and quantitative distribution of the sediments present in the gutters. In this work, the recognition of the bottom morphology of this Estuary, through bathymetric and sonographic analysis, aimed to integrate new data to studies already carried out and to evaluate the influence of surface and bottom currents on the bed modeling. The use of the “Side Scan Sonar” proved to be very useful in identifying the bottom morphology and its relationship with the predominant action of tidal currents in the Guajará Estuary. It also demonstrated how sonograms can serve as a basis for comparing the different forms of resulting from local hydrodynamic variations. The Porto de Belém region, on the right bank of the Guajará Bay, is frequently subjected to dredging operations. This area partially protected from tidal currents is a site of intense and constant deposition of sediments, resulting in an accelerated silting of the channel and therefore making dredging indispensable, under penalty of compromising the operation of that Port. These operations make any attempt to establish a morphological pattern there and relate it to the action of the currents extremely difficult. The circulation of water in the Guajará Estuary, promoted by variations in tidal currents and river discharge, results in the upstream waters predominantly falling on its left bank, developing great depths in this area and progressive erosion on the eastern side of Ilha das Onças. . In the northern portion of the Ilha das Onças Channel, in the deeper zones, the lineations of currents and the “sand waves” field are the most frequent and important sedimentary bottom features in the interpretation of the hydrodynamic conditions of the Estuary.
Acesso aberto (Open Access)
Estudo de geossistema do Lago Ariri – Ilha do Marajó – Pará.
(Universidade Federal do Pará, 1988-12-30) VITAL, Helenice; FARIA JUNIOR, Luis Ercílio do Carmo; http://lattes.cnpq.br/2860327600518536
Acesso aberto (Open Access)
Estudo geológico da sequência Camiranga nordeste do Pará.
(Universidade Federal do Pará, 1985-09-17) IGREJA, Hailton Luiz Siqueira da; FARIA JUNIOR, Luis Ercílio do Carmo; http://lattes.cnpq.br/2860327600518536
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Estudo hidrodinâmico e sedimentológico do Estuário Guajará - Belém (PA)
(Universidade Federal do Pará, 1987-08-22) PINHEIRO, Roberto Vizeu Lima; FARIA JUNIOR, Luis Ercílio do Carmo; http://lattes.cnpq.br/2860327600518536
This work presents the hydrodynamic and sedimentological characteristics of the Guajará Estuary, in the vicinity of the city of Belém. Its approach covers geological and geomorphological aspects, the behavior of waves, winds, tides, tidal currents and the investigation of the physical-chemical parameters of the waters, with the objective of sketching a quantitative model for this environment in addition to presenting a proposal for the evolution region physics. From the oceanographic point of view, the Guajará Estuary is characterized by the absence of marked thermal stratification, being classified as partially mixed, type B in the Pritchard classification (1955), with appreciable lateral variations in salinity. It is subject to a circulation mechanism controlled by strong tidal currents, which define easily individualized flood and ebb channels. Two main wind systems are responsible for the formation of several sets of waves with characteristics that will depend on their speed, intensity, duration time and direction in relation to the geography of the estuary. The tides and tidal currents interfere decisively in the formation of waves. The dynamic tide has an average amplitude in syzygy and quadrature, in the Port of Belém, around 3.0 m and 2.5 m respectively. The tidal currents on the surface, during the moments of change of direction, show a complex mechanism of circulation, always obeying the characteristics of individualization of the flood and ebb channels. The salt tide inflow mechanism also follows this pattern. Conductivity proved to be the most important parameter for defining the salt tide intrusion mechanism. Important variations in the average values of pH, O2 concentration, concentration of suspended material and conductivity in estuarine waters follow, approximately, the seasonal variations during the year marked by very rainy periods followed by the dry season. Hourly variations during tidal cycles, as well as variations arising from the fortnightly movements of the Moon (syzygy and quadrature) are similarly important. The water temperature follows the air temperature variations in the region, with expressive daily amplitudes. The Holocene sediments that fill the estuarine trough are predominantly sandy, ranging from selected to well selected, sometimes silty. The sedimentation is marked by the hydrodynamic conditions of the environment, being recognized two important textural facies: Muddy Facies and Sandy Facies. The distribution of these textural facies apparently oscillates as a function of tidal periodicity. The pelitic fraction of the estuarine sediments is composed of kaolinite, illite, smectite and stratified illite-smectite, with traces of chlorite still occurring. In the sandy fraction, quartz is the main mineral in association with iron oxide grains. Among the transparent heavy minerals, staurolite, tourmaline, kyanite, zircon, epidote and amphiboles predominate, in addition to garnet, rutile and andalusite. As main source areas, the Tocantins and Guamá rivers are pointed out. In addition to these, the Barreiras Group and the Holocene Lands must supply the estuarine bed with sediments. A geological-geomorphological evolutionary model for the Guajará Estuary is proposed, assuming the age of its implantation from the Lower to Middle Holocene, associated with the manifestations of the Flandrian Transgression.
Acesso aberto (Open Access)
Estudo litoestratigráfico do permocarbonífero da Bacia do Maranhão
(Universidade Federal do Pará, 1991-12-11) CABRAL, Natalina Maria Tinôco; FARIA JUNIOR, Luis Ercílio do Carmo; http://lattes.cnpq.br/2860327600518536
The Maranhão Basin, located in the N-NE region of Brazil, mainly in the states of Maranhão and Piauí, covers an area of approximately 600,000 km2. This basin had its framework formed in the Eopaleozoic, probably as a consequence of the collision between the Amazon and Brasiliana platforms, being considered of the intracratonic type or simple interior of the IS type. The sedimentary column of the Maranhão Basin is composed mostly of Silurian to Cretaceous rocks, with a thin Tertiary and Quaternary cover. The Piauí and Pedra de Fogo Formations represent the Permocarboniferous of this sedimentary column. The lithofaciological characterization, determined by means of drill cores in the two formations, was developed in several vertical profiles. The data obtained, compared to those in the literature, made it possible to define the various depositional environments. The sediments of the Piauí Formation can be arbitrarily divided into two members (Lower and Upper). The Lower is predominantly made up of coarse to very fine sandstones, with intercalations of shales and siltstones and rare levels of conglomerates. The Upper Member is composed of medium to very fine sandstones, with intercalations of carbonates, shales and siltstones, and subordinate levels of flint and evaporites being common. This Formation has an average thickness of 260 meters, being thicker in the central part of the Basin. Its lower contact with the Poti Formation, of the Lower Carboniferous, is discordant, and the upper one with the Pedra de Fogo Formation is gradual. These sediments belong to a desert system, with a brief marine transgression. Palynological analyzes of samples from the 1-MD-1MA well of the Piauí Formation show a palynological association constituted by the following genera: Puncttatisporites sp., Virkkipollenites cf. obscurus, Apiculatisporis sp. And Patonieisporites ap. This palynological association confirms the upper carboniferous age for the Piauí Formation. The Pedra de Fogo Formation is divided into three members (lower, middle and upper) with no formal stratigraphic connotation. The Lower Member consists of pelitic (siltite/shale), carbonate and evaporitic rocks, with less frequent contributions of flint and sandstones. It has an average thickness of around 45 meters. The Middle Member is characterized by a cyclic succession of siltstones, shales, sandstones and sometimes thick flint layers. Its thickness increases towards the center of the Basin, measuring on average about 44 meters. The Upper Member is characterized by sequences of siltstones, shales, carbonates and silexites. Subordinately, there are evaporites and sandstones. An average thickness of 58 meters is estimated, being thicker towards the west of the Basin.
Acesso aberto (Open Access)
Estudo sedimentológico e estratigráfico dos sedimentos holocênicos da costa do Amapá - setor entre a ilha de Maracá e o cabo Orange
(Universidade Federal do Pará, 1994-02-21) MENDES, Amilcar Carvalho; FARIA JUNIOR, Luis Ercílio do Carmo; http://lattes.cnpq.br/2860327600518536
Acesso aberto (Open Access)
Morfoestratigrafia e evolução holocência da planície costeira de Salinópolis, nordeste do estado do Pará
(Universidade Federal do Pará, 1996-10-18) SILVA, Marcio Sousa da; FARIA JUNIOR, Luis Ercílio do Carmo; http://lattes.cnpq.br/2860327600518536
Acesso aberto (Open Access)
Morfoestratigrafia holocênica do sistema flúvio-deltáico do rio Jarauçu/Baixo Amazonas
(Universidade Federal do Pará, 1997-04-20) NASCIMENTO, Mário Carlos Hermes; FARIA JUNIOR, Luis Ercílio do Carmo; http://lattes.cnpq.br/2860327600518536
Acesso aberto (Open Access)
A planície costeira do Amapá: dinâmica de ambiente costeiro influenciado por grandes fontes fluviais quaternárias
(Universidade Federal do Pará, 1997-12-14) SILVEIRA, Odete Fátima Machado da; FARIA JUNIOR, Luis Ercílio do Carmo; http://lattes.cnpq.br/2860327600518536
The Amapá State is located at the extreme north of Brazil. The geographic boundaries are The French Guyana (N); The Pará State (W and S), and the Atlantic Ocean to the east. The Amapá coastal plain comprises more than 300 Km of sediments deposited from the north of Amazon river through the Cabo orange, at the extreme north of the Amapá State. It reaches 120 Km width near Cabo Norte and becomes near 10 Km width near Cunani, enlarging again through the Cabo Orange. The aim of this research was to understand how the structural arcabouce and the sea level changes conditionated the development of holocenic deposits and the consequent coastal plain evolution. The Amapá Coastal Plain is inserted into the Amazon River Mouth Sedimentary Basin which is characterized by two grabens (Limoeiro e Mexiana) and two platforms, Pará e Amapá, respectively. The structural elements has an deep relation with the drainage network and throughout them and them behaviour, it was possible the identification of neotectonic records. As a low gradient region, the drainage net answered to the pressures exerted by this factors, becaming an important tool to evaluate the morphological changes ocurred during the geologic time. At the Amapá coastal plain it was possible to identify both, an actual an a paleodrainage net as well. The phisiographic and morphological characteristics of the Amapá coastal plain are defined by the regional structural arcabouce. Two phases of development were considered: 1) Pre-Holocenic Phase; 2) Holocenic Phase. The alluvial processes and the relative sea level positions contributed to the coastal plain remodelling. The re-arrangement aí the drainages to the actual layout is related to the neotectonic processes ocurred after Barreiras Group deposition which probably is still acting. Two morphological domains were defined to the Amapá coastal plain by BOAVENTURA & NARITA (1974): The north domain shows the predominance of marine processes while the south domain is influenced mainly by fluvial processes. The oceanographic and atmospheric parameters (tides, currents and trade winds) ocurring at the Amazon Shelf exerts a clear effect at the coastline, and the morphology, determined by the tectonic arcabouce propitiate the erosional and deposítional processes, depending of it relative position to the regional base level. The relative sea level position during the Holocene did play an important role on the Amapá coastal plain evolution. The sea levels position were recorded throughout the Calçoene Chenier Plain and the Cunãni-Cassiporé Chenier Plain which evolution are deeply related to the Cabo Cassiporé built process.
Acesso aberto (Open Access)
Sedimentação holocênica no estuário do rio Araguari – AP
(Universidade Federal do Pará, 1996-04-11) ROSA-COSTA, Lúcia Travassos da; FARIA JUNIOR, Luis Ercílio do Carmo; http://lattes.cnpq.br/2860327600518536

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