Navegando por Assunto "Monte Alegre - PA"

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Acesso aberto (Open Access)
Aplicação de Zr/Ti-PILC no processo de adsorção de Cu(II), Co(II) e Ni(II) utilizando modelos físico-químicos de adsorção e termodinâmica do processo
(2008) GUERRA, Denis de Jesus Lima; AIROLDI, Claudio; LEMOS, Vanda Porpino; ANGÉLICA, Rômulo Simões; VIANA, Rúbia Ribeiro
The aim of this investigation is to study how Zr/Ti-PILC adsorbs metals. The physico-chemical proprieties of Zr/Ti-PILC have been optimized with pillarization processes and Cu(II), Ni(II) and Co(II) adsorption from aqueous solution has been carried out, with maximum adsorption values of 8.85, 8.30 and 7.78 x10-1 mmol g-1, respectively. The Langmuir, Freundlich and Temkin adsorption isotherm models have been applied to fit the experimental data with a linear regression process. The energetic effect caused by metal interaction was determined through calorimetric titration at the solid-liquid interface and gave a net thermal effect that enabled the calculation of the exothermic values and the equilibrium constant.
Acesso aberto (Open Access)
Estudos hidrogeoquímicos e geofísicos na região da Braquidobra de Monte Alegre-PA
(Universidade Federal do Pará, 2005-04-11) LOPES, Elem Cristina dos Santos; VILLAS, Raimundo Netuno Nobre; http://lattes.cnpq.br/1406458719432983
The Monte Alegre brachyanticline is located in the central-western Pará and is one of the most striking structures of the Paleozoic Amazon sedimentary basin. The dome outcropping surface is elliptical with axes of 30 and 20 km trending NESW and NW-SE, respectively. At the present erosion level, rocks of the Ererê, Barreirinha, Curiri, Oriximiná, Faro, Monte Alegre, Itaituba and Alter do Chão formations, as well as the Penatecaua diabase are exposed. Thermal springs with temperatures from 29 to 37ºC issue out of the Ererê Formation. The present study focuses on the physico-chemical characterization of surface and groundwater that occur within the dome and on the interaction with their mineral environment. In addition, the thermal waters are also characterized isotopically and their subsurface temperatures estimated with basis on the silica and Na-Ca-K geothermometers. Gravimetric and resistivity methods were applied aiming at detecting potential sources that could account for the heating of the thermal waters. The Piper diagrams show a wide chemical variation for both the surface and groundwater which spread over the bicarbonate, calc-sulfate and sodic-chloride fields. The thermal waters are chemically more homogeneous and fall on the bicarbonate and sodic-chloride fields. This variability reflects the composition of the rocks through which the waters migrate, whose components result mainly from hydrolysis and redox reactions involving pyrite and sulfate minerals. Most water samples are in equilibrium with kaolinite as deduced from activity diagrams constructed at 25ºC, 1 atm and at quartz saturation. The thermal water samples cluster near the boundary kaolinite-sericite, whereas a few samples of surface waters that drain the Itaituba Formation plot near the line separating the kaolinite and leonhardite stability fields. The samples of the Menino Deus thermal spring collected in October/2002 reached equilibrium with sericite but failed to equilibrate with paragonite despite their Na/K ratios being higher than unity. Furthermore, most water samples are saturated with quartz. During the dry season, sample FT-27 and those from the Menino Deus thermal spring presented higher silica contents causing them to equilibrate with pyrophyllite. Isotopic data show that the Monte Alegre thermal waters have a meteoric origin with δ18O and δD values coincident with the global meteoric water line, although slightly enriched in deuterium. The excess of deuterium varies seasonally, being recorded values of 11,8-14,8 ‰ in the dry season and 4-9,5 ‰ in the wet season. Sub-surface temperatures for the thermal waters estimated with the silica geothermometer yield mean values of 71°C (wet season) and 83°C (dry season). Average water circulation depths ranging from 1560 m (wet season) to 1900 m (dry season) were calculated assuming a geothermal gradient of 30°/km and using the estimated sub-surface temperatures. After infiltrating into the ground, these meteoric waters are heated and rise back to the surface through a channel way network, particularly NE-SW and N-S-trending faults which truncate the brachyanticline flanks. Gravimetric surveys allowed to infer the presence of a lacolith-like body at a depth of about 1.3 km. This body is thicker close to the central portion of the brachyanticline. Contact relationships between sedimentary units and the laccolith could also be defined. Likewise, fractures and faults could be mapped at depth whose traces are visible on SRTM radar images. Resistivity profiles did not identify any thermal anomaly in the area, but they confirm the lithological diversity of the geological units as well as faults that may have served as conduits to the fluids.
Acesso aberto (Open Access)
Evolução do sistema agrário na margem esquerda do Baixo Amazonas
(Universidade Federal do Pará, 2002-06-17) OLIVEIRA, Myriam Cyntia Cesar de; REYNAL, Vincent de; http://lattes.cnpq.br/4765997606833645
Acesso aberto (Open Access)
O gênero microstrates lacordaire (Curculionidae : Baridinae): sistemática, filogenia e evolução da associação com palmeiras hospedeiras
(Universidade Federal do Pará, 1997-03-11) ROCHA, Roberta Valente da; GORAYEB, Inocêncio de Souza; http://lattes.cnpq.br/2391620537048479
A revision and phylogenetic analysis of the genus Microstrates is presented based on new characters discovered in the course of this study, and on others previously know from the literature. Eleven species are recognized, vvhich can be identified by the key presented. Two new species are described: Microstrates almiri sp. n., Caxiuanã and Belém, Pará; and M. pinrima sp. n., Monte Alegre, Pará. Microstrates bipunctatus Hustache, 1951 is considered a synonym of M. cocois Bondar, 1941. The phylogenetic analysis of the species Microstrates resulted in a hypotesis that may be expressed parenthetically as follows; ((M. cocoscampestris (M. abbreviatus (M. rufus, M. hatschbachi))) ((M. M. piririma) (M. cocais (M. cearanus, M. ypsilon) (M. cucullus, M. bondan)))). The first records of the palm hosts of M. almin sp. n., M. pirinma sp. n. and M rufus Hustache are presented. The species M. almin sp. n. and M. pirinma sp. n., collected in Pará state, represent the first record of Microstrates in the Amazonian Region. Ali species are redescribed and their most important structures for the identification are illustrated. The collection of Weevils in differents species of palms in Pará and Amazonas states confirms the hypothesis of a exclusive association of Microstrates with palms of the genera Syagrus, Butia and Cocos, and also that each species of Syagrus and Butia host only one species of Micro strates. The cladogram mapping and optimization of host palm associations of Microstrates supports the following hypothesis: association with the genus Syagrus is plesiomorphic, with Butia is apomorphic, and with the coconut (Cocos nucifera) is explained by colonization events.
Acesso aberto (Open Access)
Imigração e ocupação na fronteira do tapajós: os japoneses em Monte Alegre – 1926-1962
(Universidade Federal do Pará, 2007-05-04) ISHISU, Tatsuo; FIGUEIREDO, Aldrin Moura de; http://lattes.cnpq.br/4671233730699231
As soon as Dionísio Bentes assumed the paraense government command in 1925, he tried to stimulate the colonization of sertão paraense in order to become the agricultural production more dynamic. To accomplish the project, the government tried hard to attract the interest of Japan, offering for free lands for colonization. As result of this diplomatic agreement made between interested parts, from the end of 1929 the migratory process which spread until 1962 was begun, with interruption between 1937 and 1952. During almost three decades, about 1.600 families have disembarked in the paraense port. Most of them fixed in Pará state, forming a significant community of immigrants and their descendants. This paper is about the process which led the migration, construction of the way of life in Amazônia and rework of identity in the new environment. The main approach is Monte Alegre city colonization, in Baixo-Amazonas paraense, although it also refers to other localities in Pará and Amazônia. The analysis involves an effort to argue as much the colonizing process as the exercise in the construction of memory by the immigrants.
Acesso aberto (Open Access)
Pelas trilhas dos filhos do sol e da lua: memórias das pinturas rupestres de Monte Alegre, Pará, Amazônia, Brasil
(Universidade Federal do Pará, 2014-10-14) SILVA, Arenildo dos Santos; PACHECO, Agenor Sarraf; http://lattes.cnpq.br/5839293025434267; SCHAAN, Denise Pahl; http://lattes.cnpq.br/9087840228167206
The present work aims to reflect on the set of narratives about the cave paintings of the mountain ranges region of Monte Alegre, Pará, in the seek to understand the meanings that the archaeological heritage takes within contemporary social relations, in particular, those built according to the logic of traditional populations. The study begins with a historical dialogue through the first narratives on these images recorded by travelers and naturalists since the nineteenth century, afterwards it brings for discussion the works and knowledge produced by archaeological science in recent decades, and finally, it also adds the voices of residents of the Village of Ererê and surroundings about these iconographies. The dissertation was constructed from the interstitium between Anthropology, Archaeology and History, because the information that supported the research were obtained from reports of travelers, works of archaeological research, interviews, observation and the living together with residents of the village. The result is a tangle of distinct voices which weave, intersect and echo in the formation of a kaleidoscope of narratives composed by fragments of worlds, guided in the experiences, in the relationship with the social life and the lived present. The paths taken indicate reflections about the heritage policy in the Amazon, and more widely reflections of the search according to a decolonial praxis of science.
Acesso aberto (Open Access)
A sucessão siliciclástica-carbonática neocarbonífera da bacia do Amazonas, regiões de Monte Alegre e Itaituba (PA)
(Universidade Federal do Pará, 2010-03-14) LIMA, Hozerlan Pereira; NOGUEIRA, Afonso César Rodrigues; http://lattes.cnpq.br/8867836268820998
Neocaboniferous deposits of Morrowanian age in the Amazon Basin, northern Brazil, characterize the transition zone between Monte Alegre (siliciclastic rocks) and Itaituba (carbonate rocks) formations. The outcrop-based facies and stratigraphic analyses of this up to 40m thick succession, exposed in the Monte Alegre and Itaituba regions, State of Pará, allowed the recognition of five facies associations (FA), representative of a transitional desertic to coastal system, comprising: eolian dune/interdune (FA1), sandy sheet/wadi (FA2), lagoon/washover (FA3), beach/tidal flat (FA4) and lagoon/tidal delta (FA5). FA1 contains bimodal fine to medium-grained sandstone with medium-scale trough cross-stratification, subcritically climbing translatent stratification and inversely graded lamination (dune deposits). Massive fine sandstones with root marks suggest development of paleosols, while adhesion warts indicate eolian grain migration on wet interdune surface. FA2 comprises fine to medium-grained sandstone with even-parallel stratification and subcritically climbing translatent stratification, related to deflation, while fine to medium-grained sandstone with tangential and recumbent-folded cross-stratification and convolute bedding suggest migration of high-energy ephemeral rivers. FA3 with laminated mudstone and fine-grained sandstone with climbing-ripple cross lamination, hosting the ichnofossil Palaeophycus, suggests a low-energy environment of lagunar/washover type. FA4 is characterized by fine to medium-grained sandstones with planar and low-angle cross-stratification, interbedded with lenticular dolomite, locally truncated by fine to medium-grained sandstones. These facies correspond to the zone of swash and backwash on beach environment, locally cut by small channels, while the carbonate is interpreted as precipitated in ponds. FA 4 also comprehends mudstones with mudcracks and mud curls as well as small to medium-scale planar cross-bedded sandstones with mud drapes lining foresets and reactivation surfaces, suggesting migration of sandwaves in intertidal zones. FA5 is represented by dolomitized limestones (mudstones, wackestones, packstones and grainstones) containing vuggy and moldic porosities. Bioclasts include brachiopods, echinoderms, foraminifers, ostracodes, bryozoans, trilobites, mollusks and non-fragmented corals, and furthermore the trace fossil Thalassinoides. Additionally, this facies association comprises conglomerates with pebbles of dolomitized limestones, fine-grained sandstones with low-angle cross-stratification and reactivation surfaces, locally overlaid by fine sandstones with sigmoidal cross-stratification and climbing cross-lamination, which were interpreted as tidal inlet and tidal delta deposits. The facies/microfacies associations and paleontological data presented here point to a lagoonal environment, connected in part to a coastal desert zone, and characterize the transition between Monte Alegre and Itaituba formations. The abundance of fine sands with rounded grains in carbonate facies is consistent with siliciclastic influx from the desert adjacent to coastal environment. Warm tropical conditions for the environments can be inferred from the limestones and their diverse fauna as well as from the clay minerals, principally smectite. The interbedding of siliciclastic and carbonate rocks which characterizes the end of the deposition of the Monte Alegre Formation and the beginning of the sedimentation of the Itaituba Formation justifies a unique system representation for this interval.