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.

Navegar

Agora exibindo 1 - 11 de 11

Acesso aberto (Open Access)
Análise comparativa hidroambiental das bacias do Una e da Estrada Nova, em Belém-PA, e suas implicações socioeconômicas
(Universidade Federal do Pará, 2015-03-26) LEÃO, Eduardo Araujo de Souza; ABREU, Francisco de Assis Matos de; http://lattes.cnpq.br/9626349043103626
To evaluate the effectiveness of public interventions in relation to changing social dynamics and improve the quality of life of a population is necessary to the built and application of social indicators in monitoring public management, especially when dealing with large environmental interventions. As much as these indicators are mapped, the vast majority of environmental studies where these interventions occur, the government has dedicated itself or if it does not perform and monitor efficiently the behavior of these indicators over time. In Belém, the floods in urban areas pose a serious problem for most of the municipality, especially when involving densely occupied areas, at which generate considerable damage and often irreparable, even with losses of human lives. Flooding has been a problem during periods of frequent rainfall, both in the oldest areas of the city and consolidated, as in the areas of urban sprawl, a fact compounded by soil sealing, occupation of wetlands and removal of riparian vegetation, which hinders the infiltration rainwater. Due to these environmental factors and the inattention of government in providing social amenities and physical interventions in the area of the metropolis, populations that occupy the most vulnerable parts of the city of Belém, in general have a poor quality of life, as regards the issue of the environment in which they live. In order to comparatively evaluate two different realities and really consider whether public intervention was effective and efficient and from the same include as practical application of social indicators in monitoring the public administration, was used as case for this research performed by government intervention state in the basin of Una, where he was executed the deployment of Macro Drainage Basin of Una and services contemplated drinking water supply, sewerage, storm water drainage and road system, compared with the intervention of the municipal government to bowl Estrada Nova, running, with the deployment of these services. To develop the research, the study gathered data and information collected in the basin of Una and projected future scenarios for the basin of Estrada Nova, using the same indicators. These indicators in this study were also addressed and strengthened with a hydrogeological assessment of the two basins, the analysis of quality of surface and groundwater, consideration of the incidence of waterborne diseases, the vulnerability of aquifers, configured together in a GIS specifically built for it, with the aim of evaluating the criticality of spatialization basins and identify which areas need more attention or have the best results. The study demonstrated that the physical and socioeconomic study of the two basins are similar and after the intervention in the basin of Una, any kind of indicator was monitored with a view to demonstrate the effectiveness of the intervention. The study also showed that health indicators linked to waterborne (why the intervention was also made) chosen for monitoring before and after the intervention, have partially direct connections to the environmental quality of the basin, but many indicators not could be chosen by the lack of government data. The vulnerability of the aquifer top is also concern in some quarters, in that much of the population obtains its supplies from this aquifer, which has its recharge provided, in part, by draining channels of Belém, known holders of very bad quality indices its waters and can even be characterized as true open sewers. The drainage channels and creeks of Belém, are thus responsible for directing this excess sewage into the Bay of Guajará and river Guamá through interconnection with those that have physiographic elements. Because the city has much of its area located in quotas of up to 4 meters, which is also the average annual tidal amplitude regional, these areas are subject to flooding. By way of consequence throughout the upper aquifer is vulnerable to infiltration of contaminated water channels, which in times of floods are dammed increasing the residence time in them,. The research now being evaluated scenarios and presentation indicators, this reality, leaving open the need to be constructed and monitored indicators other than the act of evaluating the effectiveness of public intervention can be more consistent. Finally the study also notes that several indicators could not be considered in the study due to insufficient and the quality of data provided by the government.
Acesso aberto (Open Access)
Aplicação do modelo hidrodinâmico no estuário do rio Caeté (NE do Pará)
(Universidade Federal do Pará, 2007-10-17) ABREU, Marcelo Wanderley Matos de; EL-ROBRINI, Maâmar; http://lattes.cnpq.br/5707365981163429
The northern coast of Brazil is trimmed by a big and complex hydrographic net, where the main river is the Amazon. This river, as well as others smaller, flow into in the Atlantic Ocean finalist the estuaries, that are frequently defined like a stretch of the river, where occurs the interaction of the ocean and fluvial waters (transition zone). The Caeté estuary is inserted at the northeast of Pará (00º43’18" – 00º04’17" S and 46º32’16" – 46º55’11" W) that suffers influence of macro-tides and semi-diurnal with medium amplitude of 5,6 m, coastal currents (mean velocity approximately 0,75 m/s), waves of 0,7 m and Trade winds that possess NE preferential direction with medium speed of 6 m/s. That estuary is situated in a tropical region of humid climate, with annual medium temperature of 27ºC and elevated precipitation with annual medium of 2500 mm/year. In this area, are also showed, the existence of seasons with distinct characteristics: rainy (December to May), dry (June to November) and intermediate. The estuary of the Caeté river is a tide-dominated estuary (as regards the physical process), that forms an extensive coastal plain (as regards the coastal geomorphology) and well mixed (as regards waters circulation).The hydrodynamic circulation in estuary is considered as an important trial and it has a lack of studies in this area until today, principally in the North’s region of Brazil, where still have a few the studies of estuarine modeling. So, for this work were adopted the use of the hydrodynamic model with the Modeling program called SisBAHIA (Environmental Hydrodynamics Base System), aiming the observation of the general aspects of the hydrodynamic circulation in different phases of tide (high tide, low tide, flood and ebb tide) in the Caeté estuary (PA) and like this validate, through the modeling, the facts (current, tides and amplitude of tide) collected in the estuary. The methodology was performed in two phases,( fieldwork and laboratory). The phase of fieldwork consisted of: (1) hoist bathymetric, linked to the Research’s Project of the SET PROGRAM/ CT-Hidro that utilized a cartographic base previously digitalized, having like base a satellite image LANDSAT-ETM+7, beyond a digital ecobatymetric and a DGPS (Differential Global Positioning System); (2) records of elevation of the sea level, through the fixation of two digital tide predictors Orphimedes OTT-Hydrometric, located in the Maguary city, where was observed daily values to each 20 minutes during 7 consecutive days with results varying of a minimum of 0,01 m to a maximum one of 5,08 m and of 0,42 to 5,18 in the point situated in the bridge about the hole of the Maguary and in the Bacuriteua city, respectively; and (3) measure the speed of the shackles utilizing a current predictor Falmouth 2D YMCA in a point inside the model, that stayed coupled to the boat during seven consecutive days and that presented values for the currents varying of a minimum of 2,95 cm/s to a maximum one of 154,59 cm/s. In the laboratory’s phase, was carried out the trial of calibration between the facts of the model with the measurements taken in the fieldwork. They were generated simulations of the hydrodynamics conditions during the flood, ebb tide, half tide flood, half tide ebb tide, and the high value of high tide and low tide, and in the neap and spring tides. Through those simulations were generated superficial maps of currents to see the different standards of circulation.
Acesso aberto (Open Access)
Caracterização hidrogeológica em área de agricultura intensiva, na microbacia do iguarapé Cumaru, nordeste do Pará
(Universidade Federal do Pará, 2003-06-30) CHAVES, Luciene Mota de Leão; TANCREDI, Antonio Carlos Felice Nicola Saverio; http://lattes.cnpq.br/3080055631075788
Acesso aberto (Open Access)
Caracterização hidroquímica dos aquíferos freáticos costeiros na cidade de Salinópolis-PA.
(Universidade Federal do Pará, 2016-06-08) RODRIGUES, Érika do Socorro Ferreira; CORRÊA, José Augusto Martins; http://lattes.cnpq.br/6527800269860568
The city of Salinópolis is located in northeast Pará, Bragantina region, on Pará State. The geology of the area is characterized by a sedimentary cover Tertiary represented by Pirabas Formation , Barreiras Group and overlying these rocks may occur sandy-clay sediments to clay-sand the quaternary called Pós -Barreiras sediments. The main hydrogeological systems Salinópolis, in general, are: a) upper aquifer system developed in the Pós-Barreiras, unconfined aquifers; b) aquifer system Barreiras, unconfined aquifers and semi-confined; c) aquifer system Pirabas, deeper confined aquifers, which is an outcropping aquifer in the region. For the study were registered 22 wells of which 17 shallow wells with depths up to 30 m (PT), two dug wells (AM) and 3 sources (FT). The collection of samples was performed at intervals of two months for a full hydrological cycle, May 2014 to March 2015. The main quality parameters investigated were water temperature, pH, electrical conductivity, alkalinity, total dissolved solids and main ions : cations (Na+, K+, NH4+, Ca2+, Mg2+) and anions (F-, Cl-, NO3- and SO42-). Hydrochemical four groups were identified in the Piper diagram: group 1 (SO4-, Cl- and Na+) that resembles the aquifer Barreiras. In the waters of group 3 rich in calcium and bicarbonate is identified with the Pirabas water aquifer (HCO3- and Ca2+) since the water in groups 2 and 4 showed characteristics of group 1 and 3. From Piper diagrams, it was observed that with increasing water recharge the group 2 and 4 water had a water connection behavior, migrating to another group hydrochemical. In Scholler diagram, even identifying the main ions was possible to see that there are mixtures in water of the same hydrochemical group, visualized by the provision in fan. In Diagram Van Wirdum was identified climate and rocks actions on the aquifers hydrochemistry. Range distribution has been observed that with the beginning of the drought wells located in car washes and near gas stations as well as near the beach and estuarine rivers showed an increase of ions dissolved in the water. As well as in natural sources or springs there was a large increase in number of ions, especially the sulfate Climate Influence, rock, ocean waters, estuarine rivers, as well as the contribution of the aquifer Barreiras and Pirabas showed a peculiar hydrochemical composition in the waters of aquifers shallow coastal city in Salinópolis.
Acesso aberto (Open Access)
Contribuição ao conhecimento das formações Barreiras Pirabas utilizando-se ferramentas da análise estrutural com vistas à aplicação em hidrogeologia
(Universidade Federal do Pará, 2016-10-17) SILVA, Larissa Silva e; ABREU, Francisco de Assis Matos de; http://lattes.cnpq.br/9626349043103626
The existence of hydraulic connection between Barreiras and Pirabas aquifers systems in the northeast area of the State of Pará, more specifically in the metropolitan region of Belém - RMB has been raised, a few years ago, by different authors from the application of various analytical techniques. This work presents further contribution to this theme, that has been aggregated to the data and to the information obtained from the use of structural analysis tools, to understand the groundwater flow mechanism and recharge conditions, which takes place in area under consideration. The work was performed from the databases on existing wells in private and public agencies. The performed structural analysis considered the geometric-kinematic elements present in the mentioned water systems and it advanced in the knowledge of the tectonic processes that have led to the conformation of the geometric arrangement present in the area, considered essentially as neotectonic. It was found that the development of brittle tectonic structures, especially holes, printed on regional rocks that enclose the water systems, leading to spatial composition of morpho-structural blocks arrangements horsts and grabens limited preferably by the NE and SW discontinuities resulting from the interaction of normal faults with strike-slip faults. The boundaries of these blocks, always marked by failures allow the interconnection of the movement of water from aquifers of different spatial positions systems, sustained by the principle of communicating vessels, the elapsing the mixture of water contained in each one of them individually. So it is impossible to keep the model advocated by several authors in the literature of regional aquifer confinement. On the other hand, the development of potentiometric maps and flow in regions of sedimentary rocks, where it is called homogeneous media, as this case is of the RMB cannot be done without considering the structural analysis, geometry and kinematics, otherwise it would be misunderstood in the preparation of such results and mistaken hydrogeological interpretation. Thus, it is necessary to review the methodologies for the preparation of these important instruments in order to obtain more precise results on the flow mechanisms, recharge and discharge of water systems which has been developed and answered in this work.
Acesso aberto (Open Access)
Fatores controladores do quimismo de águas subterrâneas da região nordeste do Pará
(Universidade Federal do Pará, 1996-11-10) SOUZA, Eliene Lopes de; LIMA, Waterloo Napoleão de; http://lattes.cnpq.br/1229104235556506
This work was carried out in the northeastern region of Pará State with the purpose of studying the factors that control the chemism of both spring and well waters. They are waters of aquifers constituted of alteration products of granites (Tracuateua), metassediments(Santa Luzia), metavolcano-sediments(serra do Piriá) and apatite-hornblendite (ilha de Itacupim). Waters in contact with limestones were also studied. Most of these waters purposes. The are used with local population supply waters were collected in restricted zones covered by Amazonian rainforest, in areas that support second growth vegetation(capoeira) and in jungle clearings. The collect period was 1992 dry season, 1993 dry and rainy seasons, 1994 rainy season and in 1995 dry and rainy season. Petrographic and mineralogical study of alteration products and in some cases of the bedrock, indicate the possible influente of these materials in the water composition. The pedogenetics processes taking place in the studied zones were characterized. The potential of these zones for occupation purposes were also evaluated. In Tracuateua, Santa Luzia and also in the Serra do Piriá saprolitic tone, the aquifers are formed by highly weathered products, constituted basically by quartz, kaolinite and iron oxi-hidroxides. In the metavolcano-sediments/lithomarge or apatite-hornblendite/lithomarge interface, minerals like biotite, albite or apatite are frequents. The upper layer (20 cm deep) of the soils in these areas is poor in bases and displays a pH value of about 5,0. The alteration products of calcareous are base saturated, presenting pH about 8,0 and are constituted of quartz and kaolinite, with calcite in small proportion. The content of organic material in soils, about 12% in preserved areas and less than 3% in degraded areas, reflects the nature of the vegetal coverage. Waters in contact with the most weathered products are chloride and sodium rich, acidic (average pH 4,4), poor in solutes(TDS < 30 ppm), mainly of pluvial origin. Waters in contact with less altered products, derived from metavolcano-sediments and apatite-hornblendite, raise the base, silica or phosphate content, which are derived principally from the hydrolysis of primary minerals. In waters from calcareous areas the relation HCO3:Ca+Mg1 indicates carbonates dissolution. They are calcium and bicarbonate rich, righ in solutes(average TDS 230 ppm), and presents pH value about 7,0. When in contact with clay layers that contains pyrite, waters becomes sodium and sulphate rich and acidic (pH 5,0). Marines aerosols, vegetal detritus and domestic waste waters are localized sources of solutes, while the organic acids, together with the scarcity of bases, are responsible for water acidity. The upper layer of the soils of the degraded areas shows intense eluviation with subsequent relative enrichment in quartz. The use of these lands for agricultural purposes requires nutrient reposition. Where sandy-clay sediments cover limestones, the pH value is about 5, what enables the plants to take more efficiently the marine nutrients which abound in the calcareous sediments.
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.
Acesso aberto (Open Access)
Impacto da urbanização na qualidade das águas subterrâneas nos bairros do Reduto, Nazaré e Umarizal - Belém/PA
(Universidade Federal do Pará, 2004-01-29) CABRAL, Natalina Maria Tinôco; MANOEL FILHO, João
The study evaluates the urban impacts in the groundwater quality of Barreiras aquifer, caused mainly by nitrogen compounds (nitrate and ammonium) from domestic sewage and aromatical composites (benzene, tolueno, ethylbenzeno and xylenes - BTEX), from underground fuel storage tanks of gasoline and diesel. The study was carried out on an area of 15 Km2, in the quarters of the Reduto, Nazaré and Umarizal in city of Belém/PA. The used methods incluided a cadastre of wells, analyses and stratigraphic well log correlations, execution of 9 periods of sampling, chemical analysis of water from and interpretation of results. The unsaturated zone, in the study area, has thickness varying of I to 9m, being conditional to the seasonals variability. Mineralogical studies of sediments collected in drill rig wells had defined a domain of quartz and, of a more subordinated form, caulinite. The grain sized analysis show a predominance of the fractions silte sand, silte arenaceous and silte clay. Test of infiltration indicated value corresponding to a material silte to silte arenaceous. Sediments with these textures, associates to the varied infiltration capacity, mineralogic composition, water levei flat and raised load of contaminants, of mainly septic and casspools, can lead to the contamination of the aquifers of the area. The aquifers ones identified are correlated to the aquifers of the Barreiras Group, having been defined two main ones. First, the most superficial one, was classified as unconfined-leaky, and as the second aquifer one was characterized as confined-leaky. The water level, by diverse reasons, had not been measured during the execution of this work. In this case, the presented measures correspond to those done ones during the time of drilling of the wells, in which had varied of less of lm, in the areas of lower topographical quotas, until 11m in the wells located in the more raised paris. Vulnerability data had established mainly that, to a large extent of the area, the Barreiras Aquifer presents contamination possibility, considering that the studied area is urban and, consequently, concentrate some potentially polluting activities. The interpretation of the directions of groundwater flows, of the studied area, shows that the main lines of preferential flow are guided for the center of the area, containning the quarter of the Reduto and part of the Nazaré. The global behavior of the variables shows that the hydrogeochemical characteristics of studied waters are differentiated, when compared with the regional standard. The main parameters that had marked this differentiation had been the electric conductivity, chloride, sodium, pH, ammonium and nitrate. It is standed out that the grades of ammonium and nitrate are above or very Glose to the limit to potability standards, and that such parameters are the main contamination indicators of waters by effluent domestic sewage. The global analysis showed for nitrate a positive correlations with electric conductivity and a weak correlation with chloride, sodium, calcium, sulphate and hardness. For ammonium one observes a positive correlation with chloride and negative correlation with calcium, sulphate, pH and hardness. This study it allowed to indicate the conductivity, chloride and calcium as good pointers of the contaminations. The effected factorial analyses had come to confirm the main comments gotten in the study of correlations. The statistical study by period of sampling, they indicate that the regional seasonality is influencing only in secondary way in the chemical behavior the studied waters. The slight enrichment, of some components, in the rainy period can be explained because, in this period, the groundwater level is raised until next to the ground , being next to the contamination sources. In the study of correlation by period of sampling, the results can be considered, without exception, similars to the gotten ones in the analysis of correlation made with the global data. The statistical analysis for a series of wells had indicated that the wells, when analyzed individually, they had shown a relatively homogeneous behavior along the periods, but when compared between itself, it was possible to distinguish wells with values always raised from those with the raised values less. In the study of the behaviors for nitrate and ammonium, it was observed that the wells, when analyzed individually, they had homogeneous behaviors. On the other hand, the joint study of the wells it allowed to the classification of 4 main styles of behavior for nitrate and ammonium. Style 1 would correspond the wells with high values of nitrate and low values of ammonium; style 2 would be characterized by high values to nitrate and ammonium; style 3 would correspond the wells with low to intermediate concentrations the nitrate and high the relatively high ammonium grades and, finally, style 4 would be translated by lower grades for ammonium, followed for intermediate nitrate grades. These styles can mean greater or minor distance of active sources of contamination, that would be, therefore, the preponderant factors in the hydrogeochemical characterization of the wells in an urban area as the studied one. In two wells a more detailed water sampling was effected. These samplings had evidenced, one more time, to little influence of the seasonality in the hydrochemical characterization of the studied wells. To identify the main types of waters, representative samples of the registered in cadastre wells had been located in the diagrams of Piper. The results had shown a trend, so that, the samples, independent of the period of sampling, to be concentrated in calcium chloride sulfate, cl sodium chloride and sodium nitrate cloride hydrochemical facies. These behaviors reflect that they are being strong affected for antropogenic factors, in detriment of natural processes. The analysis of the space distribution, of the main parameters, showed that, for nitrate, the more raised grades are located in the central and south portion of the area. The ammonium presented an inverse relation to the one of nitrate, with more raised grade the northwest and northeast of the area, diminishing for the center of the area. The map of electric conductivity coincides, in good part, with the one of nitrate, while that the chloride iso-grade map is, in a general, similar way to the one it ammonium. The iso-grade map of pH did not show any trend of correlation with nitrate. These correspondences had coincided with the comments of the studies of correlations. In the study of water contamination by gasoline/diesel, three critical areas were defined. The study finally sugests that, in regard to water samples with qualitative identification of diesel and or gasoline, the main biodegradation process, bisede the aerobic one, seems to be of nitrate one.
Acesso aberto (Open Access)
Influência da sazonalidade sobre as águas estuarinas dos furos da ilha de Colares (baía do Marajó)
(Universidade Federal do Pará, 2014-12-17) GUIMARÃES, Robledo Hideki Ebata; EL-ROBRINI, Maâmar; http://lattes.cnpq.br/5707365981163429
The characterization of surface and interstitial waters in estuaries is critical to unravel the environmental conditions, environmental quality and seasonal changes, which may occur in smaller space such as the hole in the island of Colares. This work aims to show the influence of seasonality in estuarine waters in the north and south of the mouth of the hole island of Colares and the contribution of pore waters to surface waters. The physical and chemical parameters and nutrients are included: rainfall (IP), temperature, salinity, pH, electrical conductivity, total dissolved solids, suspended particulate matter, dissolved oxygen, Secchi depth, nitrate, nitrite, N-ammonia, phosphate, silicate and sulfate. The determination of these parameters occurred simultaneously in each mouth of the hole necklaces over a tidal cycle (13 hours) in rainy (04/10/2013) and drier (10/05/2013) periods. The results show that seasonality affects abiotic conditions of estuarine waters bore the island of Colares and deduces that P1 is the most important factor to effect the changes of physical and chemical parameters, and especially the higher charge mobility, availability and distribution of dissolved nutrients, which were found in higher concentrations in the rainy season. Although the nutrients nitrate and N-ammonia were considered very high at the mouth North, possibly related to the influence of anthropogenic activities. However were considered within the limits established by CONAMA Resolution 357/05. Mouth occurred in South pH levels outside the standard stipulated by Resolution CONAMA, but the phenomenon was considered natural since in this specific is distant from anthropogenic activities. In less rainy period the N-ammonia was found to be absent in mouth North and South. The mangrove was considered as a source of salinity, silicate and sulfate to surface waters.
Acesso aberto (Open Access)
Recursos hídricos subterrâneos de Santarém: fundamentos para uso e proteção
(Universidade Federal do Pará, 1996-10-10) TANCREDI, Antonio Carlos Felice Nicola Savério; REBOUÇAS, Aldo da Cunha; http://lattes.cnpq.br/7322958772719317
Investigations carried out in the region of Santarém, in an area of 900 km2, outlined the hydrogeological conditions, and the technical and economic aspects for a wise use of groundwater The region within equatorial humid climate has a mean annual precipitation of 1,911.2 mm. The mean annual discharge of São Brás stream in 147.78 km2 of drainage area was 2.17 m3/s and the base flow has the annual volume of 37.0 x 106 m3. The aquifers consist of Quaternary alluvial sands of little areal distribution, and of Cretaceous sands, sandstones, and gravel of the Alter do Chão Formation, which are widely distributed in the whole area. The thickness of the hydrogeological system of the Alter do Chão Formation is 600 m. In the upper part the aquifer is unconfined, with an average thickness of 50 m, and underlying it, confined aquifers with a total thicknesses of 430 m, interbeded with aquicludes and/or aquitards. The hydraulic characteristics have been determined through pumping tests. The hydrodinamic parameters reveals that the transmissivity values range from 130 to 790 m2/day, showing large capacity of groundwater yield. The groundwater quality has shown very low concentrations of chemical constituents in solution, within the standards of potability; whereas the hydrogeochemical characterization classifies the waters into sodium-chloride type, and no dominant type, both for cations and anions. The concentration of the main ionic species in solution show the following relationship: rNa>rCa>rMg and rCL>rHCO3>rSO4. The vulnerability of groundwater range generally from moderate to low, being the lowest values found in the southern part of the area, in the plateau. The groundwater reserves are significant, 226 x 106 m3 as renewable reserves, and 86 500 x 106 m3 as permanent reserves. Besides the magnitude of the reserves, the exploitable resources bear a high potential for induced recharging. The unitary cost of groundwater exploitation in the Santarém region indicates that they decrease with the wells depth in the unconfined and confined aquifers, ranging from R$ 0.0657/m3 to R$ 0.0727/m3, for wells down to 300 m. A comparison between exploitation costs shows that the Santarém groundwater cost ranges from 38.4 % to 42.5 % of the cost for Manaus superficial water, and from 64.5 % to 71.3 % for that in Oriximiná. The confined aquifers are naturally well protected, with excellent conditions for a public water system. There are no restrictions as for the location of wells in urban areas, and no large wellhead protection areas are necessary. The wells must be adequately isolated with upper part of the annular space cemented down to the confining layer. Even considering the favorable superficial water exploitation conditions, the initial expenditures and time spent for the building of the facilities in groundwater exploitation, are much lower. Another advantage of groundwater use is that as the water demand increases the system can be adjusted accordingly to that demand.
Acesso aberto (Open Access)
O valor econômico e estratégico das águas da Amazônia
(Universidade Federal do Pará, 2006-03-22) DUARTE, André Augusto Azevedo Montenegro; RIBEIRO, Mário Ramos; http://lattes.cnpq.br/4314158355862373; ABREU, Francisco de Assis Matos de; http://lattes.cnpq.br/9626349043103626
Water is, in itself, a natural resource that is indispensable for life, extremely important for metabolism and socioeconomic processes and vital for balancing and maintaining climatic conditions and the environment in general. The asset “water” in its ontological aspect, that is, as a substance in itself, as well as a socioeconomic entity, and the waters of Amazonia in particular, may have their ECONOMIC VALUE measured or calculated, to be expressed in monetary units, guided by the principle that these waters are a STRATEGIC ASSET. This thesis does not restrict the condition of water’s existence only to the physical liquid state of the substance, nor to the principles that the value of this asset originates or is derived from economic/financial costs of obtaining, treating, storing or distributing it, nor yet to that which is obtained under the focus of scarcity. “The Value of Non-Use” or “of the Existence” of the object of this study is the principle focus of this thesis. The Amazon region possesses the largest reserves of freshwater, tropical forest and biodiversity on the planet. The complex system resulting from this interaction, in the dynamic and functional, as well as static (stocks) aspects, is generated and its maintenance will only be possible if there is no significant alteration in the regional hydrological cycle, which is vitally important to the Earth’s climatic equilibrium, through carrying heat and humidity, and, more specifically, when it is expressed as support for productive activities in the Brazilian territory that are of great economic relevance. Thus, it is important that strategies be identified, mechanisms be created and parameters be established for managing this immense natural resource, with compensatory mechanisms and policies being presented, including the transfer of financial resources that can promote socioeconomic development for the region. The research that informed the development of this thesis has a theoretical, conceptual and multidisciplinary character, involving knowledge of geosciences (geology, meteorology, hydrology), economics, engineering, public policies, ecology and sociology, with two principal lines of thinking: hydrological and economic.

Navegar

Navegando Programa de Pós-Graduação em Geologia e Geoquímica - PPGG/IG por CNPq "CNPQ::CIENCIAS EXATAS E DA TERRA::GEOCIENCIAS::GEOLOGIA::HIDROGEOLOGIA"