47 resultados para Sistema aquífero da Bacia do Tejo

em Universidade Federal do Rio Grande do Norte(UFRN)


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The study area is within the Pirangi River Basin, eastern sector of Rio Grande do Norte state, where is located of the Parnamirim city. It has an area of approximately 370 km². Urbanization has developed much fast without an appropriate infrastructure, mainly by the lack of sewage systems, with risks of contamination of groundwater that may cause serious damage to the health of the population. The Barreiras Aquifer System groundwater in the area represents the main source of water supply for urban and rural populations. The use of groundwater occurs without adequate planning and therefore, important recharge areas are being occupied. This study was conducted to quantify the use and evaluation of the potential of groundwater, in order to increase good water quality supply and lower risks of being affected by polluting activities. With these objectives, the following activities were carried out: 268 points of water have been registered; characterization of the lithological, thickness and hydrogeological structure of the Barreiras aquifer, based on the correlation of well logs; and evaluation of hydrodynamic parameters of the aquifer, from the interpretation of results well pumping tests. It was found that the saturated thickness increases from west to east towards the sea, with values ranging from 15,47-56,5 m with an average of 32,45 m. The hydrodynamic parameters using Cooper-Jacob method were: average transmissivity of 5,9x10-3 m²/s and average hydraulic conductivity 2,82x10-4 m/s. The effective porosity is of 15%, obtained by applying Biecinski equation. The potentiometric map shows the main direction of groundwater flow, from west to east, and identifies the recharge areas corresponding to the region of the tablelands of the "Barreiras". The river valleys refer to the discharge areas of the aquifer system. The Recharge was estimated at 253 mm/year, which corresponds to the 16.4% rate of infiltration.

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The study area is within the Pirangi River Basin, eastern sector of Rio Grande do Norte state, where is located of the Parnamirim city. It has an area of approximately 370 km². Urbanization has developed much fast without an appropriate infrastructure, mainly by the lack of sewage systems, with risks of contamination of groundwater that may cause serious damage to the health of the population. The Barreiras Aquifer System groundwater in the area represents the main source of water supply for urban and rural populations. The use of groundwater occurs without adequate planning and therefore, important recharge areas are being occupied. This study was conducted to quantify the use and evaluation of the potential of groundwater, in order to increase good water quality supply and lower risks of being affected by polluting activities. With these objectives, the following activities were carried out: 268 points of water have been registered; characterization of the lithological, thickness and hydrogeological structure of the Barreiras aquifer, based on the correlation of well logs; and evaluation of hydrodynamic parameters of the aquifer, from the interpretation of results well pumping tests. It was found that the saturated thickness increases from west to east towards the sea, with values ranging from 15,47-56,5 m with an average of 32,45 m. The hydrodynamic parameters using Cooper-Jacob method were: average transmissivity of 5,9x10-3 m²/s and average hydraulic conductivity 2,82x10-4 m/s. The effective porosity is of 15%, obtained by applying Biecinski equation. The potentiometric map shows the main direction of groundwater flow, from west to east, and identifies the recharge areas corresponding to the region of the tablelands of the "Barreiras". The river valleys refer to the discharge areas of the aquifer system. The Recharge was estimated at 253 mm/year, which corresponds to the 16.4% rate of infiltration.

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The use of chemical fertilization in arable perimeters provides increased productivity, though it can eventually lead to a qualitative depreciation of groundwater sources, especially if such sources are unconfined in nature. In this context, this thesis presents results from an analysis of the level of natural protection of the Barreiras Aquifer in an area located on the eastern coast of the Rio Grande do Norte State - Brazil. Such an aquifer is clastic in nature and has an unconfined hydraulic character, which clearly makes it susceptible to contamination from surface ground loads with contaminants associated with the leaching of excess fertilizers not absorbed by ground vegetation. The methodology used was based on the use of hydro-geophysical data, particularly inverse models of vertical electrical soundings (VES) and information from well profiles, allowing the acquisition of longitudinal conductance cartographies (S), data in mili-Siemens (mS), and the vulnerability of the aquifer. Such maps were prepared with emphasis to the unsaturated overlying zone, highlighting in particular its thickness and occurrence of clay lithologies. Thus, the longitudinal conductance and aquifer vulnerability reveal areas more susceptible to contamination in the northeast and east-central sections of the study area, with values equal to or less than 10mS and greater than or equal to 0,50, respectively. On the other hand, the southwestern section proved to be less susceptible to contamination, whose longitudinal conductance and vulnerability indices are greater than or equal to 30mS and less than or equal to 0,40, respectively.

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The use of chemical fertilization in arable perimeters provides increased productivity, though it can eventually lead to a qualitative depreciation of groundwater sources, especially if such sources are unconfined in nature. In this context, this thesis presents results from an analysis of the level of natural protection of the Barreiras Aquifer in an area located on the eastern coast of the Rio Grande do Norte State - Brazil. Such an aquifer is clastic in nature and has an unconfined hydraulic character, which clearly makes it susceptible to contamination from surface ground loads with contaminants associated with the leaching of excess fertilizers not absorbed by ground vegetation. The methodology used was based on the use of hydro-geophysical data, particularly inverse models of vertical electrical soundings (VES) and information from well profiles, allowing the acquisition of longitudinal conductance cartographies (S), data in mili-Siemens (mS), and the vulnerability of the aquifer. Such maps were prepared with emphasis to the unsaturated overlying zone, highlighting in particular its thickness and occurrence of clay lithologies. Thus, the longitudinal conductance and aquifer vulnerability reveal areas more susceptible to contamination in the northeast and east-central sections of the study area, with values equal to or less than 10mS and greater than or equal to 0,50, respectively. On the other hand, the southwestern section proved to be less susceptible to contamination, whose longitudinal conductance and vulnerability indices are greater than or equal to 30mS and less than or equal to 0,40, respectively.

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One of the most important natural resources for sustaining human life, water, has been losing the basic requirements of quality and quantity sufficient enough to attend the population due to water contamination'problems, often caused by human beings themselves. Because of this, the sources of this resource are often located in remote places of the natural environment to ensure the quality of the water. However, when urban expansion began to occupy these areas, which were once regarded as distant, environmental pollution problems began to occur due to occupation of the land without planning. Based on this occurrence, this study aims to propose environmental zoning for the Maxaranguape river watershed in order to protect its water resources. This is important because this river can serve as a source of supply for the metropolitan area of Natal, the capital of Rio Grande do Norte. In accordance to this proposition, the model of natural soil loss vulnerability (CREPANI et al., 2001), the model of aquifer pollution vulnerability (FOSTER et al., 2006), and the legal incompatibility map (CREPANI et al., 2001) were used to delimit the zones. All this was done with Geographic Information System (GIS) and also created a geographic database update of the basin. The results of the first model mentioned indicated that 63.67% of the basin was classified as moderately stable / vulnerable, 35.66% as moderately vulnerable, and 0.67% as vulnerable. The areas with high vulnerability degree correspond with sand dunes and river channels areas. The second model indicated that 2.84% of the basin has low vulnerability, 70.27%) has median vulnerability, and 26.76% and 0.13% has high vulnerability and extreme vulnerability, respectively. The areas with the highest vulnerability values also refer to part of the sand dunes and river channels besides other areas such as Pureza urban area. The legal incompatibility map indicated that the basin has 85.02 km2 of Permanent Protection Area (PPA) and 14.62% of this area has some incongruity of use. Based on these results it was possible to draw three main zones: Protection and Sustainable Use Zone (PSUZ), Protection and Environmental Restoration Zone (PERZ) and Environmental Control Zone, which are divided into A, B and C. The PSUZ refer to the coastal areas of the basin, where the sand dunes are located. These sites should be areas of environmental protection and of sustainable urban expansion. The ZPRA refer to river channels, which are in high need of rehabilitation. The third zone corresponds to the rest of the basin which should have, in general, the mapping of possible sources of contamination for further control on the use and occupation of the river

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Urban centers in Pitimbu Watershed use significant groundwater sources for public supply. Therefore, studies in Dunas Barreiras aquifer are relevant to expand knowledge about it and help manage water resources in the region. An essential tool for this management is the numerical modeling of groundwater flow. In this work, we developed a groundwater flow model for Pitimbu Watershed, using the Visual Modflow, version 2.7.1., which uses finite difference method for solving the govern equation of the dynamics of groundwater flow. We carried out the numerical simulation of steady-state model for the entire region of the basin. The model was built in the geographical, geomorphological and hydrogeological study of the area, which defined the boundary conditions and the parameters required for the numerical calculation. Owing to unavailability of current data based on monitoring of the aquifer it was not possible to calibrate the model. However, the simulation results showed that the overall water balance approached zero, therefore satisfying the equation for the three-dimensional behavior of the head water in steady state. Variations in aquifer recharge data were made to verify the impact of this contribution on the water balance of the system, especially in the scenario in which recharge due to drains and sinks was removed. According to the results generated by Visual Modflow occurred significantly hydraulic head lowering, ranging from 16,4 to 82 feet of drawdown. With the results obtained, it can be said that modeling is performed as a valid tool for the management of water resources in Pitimbu River Basin, and to support new studies

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The structural knowledge of the western portion of the Potiguar Basin is still in its infancy, especially these related to NW-trending fault systems. This paper analyzes the Poço Verde-Caraúbas Fault System, which was initially recognized in subsurface. The activities involved in this study correspond to remote-sensing analysis and, in particular, to the geometric and kinematic analysis of post-rift sequences of the basin. In addition, the study aimed to determine the stress fields operating in the area. The studies were carried out in an area of 1,000 km², located in the western portion of Potiguar Basin along the Poço Verde-Caraúbas Fault System, Rio Grande do Norte State. The remote sensing imagery indicates a predominance of NW-SE-trending lineaments, consistent with the fault system under study, followed by the NE-SW, N-S and E-W directions. The tectonic structures mapped were analyzed only in outcrops of the Jandaíra Formantion. They are joints (filled or not) in all directions, but with predominance of the NW-trending joints. Faults are usually N-S-trending normal faults and NW-SE and NE-SW-trending strike-slip faults. Geodynamic analysis identified two tectonic stress fields: the first field, "Field 1" is represented by an N-S-trending horizontal compression and E-W-trending horizontal extension. This field affected the Potiguar Basin at least until the Miocene. The second field, "Field 2", is represented by an E-W-trending horizontal compression and N-S-trending horizontal extension. This is the present-day stress field and has affected the Potiguar basin since the Pliocene

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The uncontrolled growth of most Brazilian cities is not accompanied by the development of urban infrastructure. With increasing soil sealing, runoff and decreased infiltration volume, impacts on water resources and on population of the areas affected by urban growth are inevitable. This study aims to evaluate the use and occupation of a watershed and analyze the drainage system in order to control the impact using tools to integrate urban development with the drainage of rainwater in an important watershed in the Natal City, Rio Grande do Norte State. The study involved the characterization of the basin XII.4 on the land use and occupation, for the years 2005 and 2014. With the application of SWMM model was possible to analyze the impacts caused by the urbanization process in the existing drainage system, showing the two years analyzed have their areas very close to percentage saturation of impervious areas. Although the region is still predominantly single family residential, suffers increasing verticalization of mainly commercial buildings. The drainage system is inefficient for the area's needs by the year 2005. The drainage system was also tested for four variations of land use by developing scenarios. Scenario 1 is related to the year 2014, considered current. Scenario 2 was adopted the maximum rate of 80% for land use, allowed for the Natal City. Scenario 3 gives the critical condition of land use, with the area 100% impervious. Scenario 4 is applied to the existence of LID (Low Impact Device). The scenarios analysis showed that all indicate deficiency at some point of the drainage system as a result of the high degree of occupation of the area that generate higher flows than the initial drainage system capacity. With the study it became clear that the adoption of non-structural tools are effective in reducing flooding and improving the drainage system capacity.

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The uncontrolled growth of most Brazilian cities is not accompanied by the development of urban infrastructure. With increasing soil sealing, runoff and decreased infiltration volume, impacts on water resources and on population of the areas affected by urban growth are inevitable. This study aims to evaluate the use and occupation of a watershed and analyze the drainage system in order to control the impact using tools to integrate urban development with the drainage of rainwater in an important watershed in the Natal City, Rio Grande do Norte State. The study involved the characterization of the basin XII.4 on the land use and occupation, for the years 2005 and 2014. With the application of SWMM model was possible to analyze the impacts caused by the urbanization process in the existing drainage system, showing the two years analyzed have their areas very close to percentage saturation of impervious areas. Although the region is still predominantly single family residential, suffers increasing verticalization of mainly commercial buildings. The drainage system is inefficient for the area's needs by the year 2005. The drainage system was also tested for four variations of land use by developing scenarios. Scenario 1 is related to the year 2014, considered current. Scenario 2 was adopted the maximum rate of 80% for land use, allowed for the Natal City. Scenario 3 gives the critical condition of land use, with the area 100% impervious. Scenario 4 is applied to the existence of LID (Low Impact Device). The scenarios analysis showed that all indicate deficiency at some point of the drainage system as a result of the high degree of occupation of the area that generate higher flows than the initial drainage system capacity. With the study it became clear that the adoption of non-structural tools are effective in reducing flooding and improving the drainage system capacity.

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The behavior of the fluid flux in oil fields is influenced by different factors and it has a big impact on the recovery of hydrocarbons. There is a need of evaluating and adapting the actual technology to the worldwide reservoirs reality, not only on the exploration (reservoir discovers) but also on the development of those that were already discovered, however not yet produced. The in situ combustion (ISC) is a suitable technique for these recovery of hydrocarbons, although it remains complex to be implemented. The main objective of this research was to study the application of the ISC as an advanced oil recovery technique through a parametric analysis of the process using vertical wells within a semi synthetic reservoir that had the characteristics from the brazilian northwest, in order to determine which of those parameters could influence the process, verifying the technical and economical viability of the method on the oil industry. For that analysis, a commercial reservoir simulation program for thermal processes was used, called steam thermal and advanced processes reservoir simulator (STARS) from the computer modeling group (CMG). This study aims, through the numerical analysis, find results that help improve mainly the interpretation and comprehension of the main problems related to the ISC method, which are not yet dominated. From the results obtained, it was proved that the mediation promoted by the thermal process ISC over the oil recovery is very important, with rates and cumulated production positively influenced by the method application. It was seen that the application of the method improves the oil mobility as a function of the heating when the combustion front forms inside the reservoir. Among all the analyzed parameters, the activation energy presented the bigger influence, it means, the lower the activation energy the bigger the fraction of recovered oil, as a function of the chemical reactions speed rise. It was also verified that the higher the enthalpy of the reaction, the bigger the fraction of recovered oil, due to a bigger amount of released energy inside the system, helping the ISC. The reservoir parameters: porosity and permeability showed to have lower influence on the ISC. Among the operational parameters that were analyzed, the injection rate was the one that showed a stronger influence on the ISC method, because, the higher the value of the injection rate, the higher was the result obtained, mainly due to maintaining the combustion front. In connection with the oxygen concentration, an increase of the percentage of this parameter translates into a higher fraction of recovered oil, because the quantity of fuel, helping the advance and the maintenance of the combustion front for a longer period of time. About the economic analysis, the ISC method showed to be economically feasible when evaluated through the net present value (NPV), considering the injection rates: the higher the injection rate, the higher the financial incomes of the final project

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The Rio do Peixe Basin represents a main basin of northeastern Brazil and pioneering work positioned the rocks of this basin in the Early Cretaceous. However, a recent study, based on integrated pollen analysis from three wells, found an unprecedented siliciclastic sedimentary section, in the region, of early Devonian age. Therefore, the present study aims a detailed petrographic and petrological analysis of this devonian section, in the Rio do Peixe Basin and proposes a diagenetic evolution, to understand the characteristics of the porous system, identify the main reservoir petrofacies with the main factors impacting on the quality of these rocks as reservoirs and a quick study on the provenance of this section. The petrographic study was based on samples obtained from subsurface and surface. The diagenetic evolution of petrofacies and its identification were based only on subsurface samples and the study of provenance was based on surface samples. The thin sections were prepared from sandstones, pelites and sandstones intercalated with pelites. The original detrital composition for this section is arcosean and the main diagenetic processes that affected these rocks occur in various depths and different conditions, which resulted in extensive diagenetic variety. The following processes were identified: early fracture and healing of grains; albitization of K-feldspar and plagioclase; siderite; precipitation of silica and feldspar; mechanical infiltration of clay and its transformation to illite/esmectite and illite; autigenesis of analcime; dissolution; autigenesis of chlorite; dolomite/ferrous dolomite/anquerite; apatite; calcite; pyrite; titanium minerals and iron oxide-hidroxide. The occurrence of a recently discovered volcanism, in the Rio do Peixe Basin, may have influenced the diagenetic evolution of this section. Three diagenetic stages affected the Devonian section: eo, meso and telodiagenesis. This section is compositionally quite feldspathic, indicating provenance from continental blocks, between transitional continental and uplift of the basement. From this study, we observed a wide heterogeneity in the role of the studied sandstones as reservoirs. Seven petrofacies were identified, taking into account the main diagenetic constituent responsible for the reduction of porosity. It is possible that the loss of original porosity was influenced by intense diagenesis in these rocks, where the main constituent for the loss of porosity are clays minerals, oxides and carbonate cement (calcite and dolomite)

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The objective of this Doctoral Thesis was monitoring, in trimestral scale, the coastal morphology of the Northeastern coast sections of Rio Grande do Norte State, in Brazil, which is an area of Potiguar Basin influenced by the oil industry activities. The studied sections compose coastal areas with intense sedimentary erosion and high environmental sensitivity to the oil spill. In order to achieve the general objective of this study, the work has been systematized in four steps. The first one refers to the evaluation of the geomorphological data acquisition methodologies used on Digital Elevation Model (DEM) of sandy beaches. The data has been obtained from Soledade beach, located on the Northeastern coast of Rio Grande Norte. The second step has been centered on the increasing of the reference geodetic infrastructure to accomplish the geodetic survey of the studied area by implanting a station in Corta Cachorro Barrier Island and by conducting monitoring geodetic surveys to understand the beach system based on the Coastline (CL) and on DEM multitemporal analysis. The third phase has been related to the usage of the methodology developed by Santos; Amaro (2011) and Santos et al. (2012) for the surveying, processing, representation, integration and analysis of Coastlines from sandy coast, which have been obtained through geodetic techniques of positioning, morphological change analysis and sediment transport. The fourth stage represents the innovation of surveys in coastal environment by using the Terrestrial Laser Scanning (TLS), based on Light Detection and Ranging (LiDAR), to evaluate a highly eroded section on Soledade beach where the oil industry structures are located. The evaluation has been achieved through high-precision DEM and accuracy during the modeling of the coast morphology changes. The result analysis of the integrated study about the spatial and temporal interrelations of the intense coastal processes in areas of building cycles and destruction of beaches has allowed identifying the causes and consequences of the intense coastal erosion in exposed beach sections and in barrier islands

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The Pirangi beach is located in the eastern coastline of Rio Grande do Norte state, in the municipality of Parnamirim and Nísia Floresta. In it flow into Pirangi Watershed (PW), whose water receives large amounts of pollutants, mainly domestic and industrial sewage from districts where pass the rivers that consist it, compromising, thus, the bathing water quality of the Pirangi beach. Bearing in mind the importance of water sanitary quality to ensure an environment that no present risk to the bathers s health, this work had as main objective to assess the influence of the PW s waters in the bathing water quality of the Pirangi beaches. To that end, were made collections of water in the beaches and in the rivers with the intention of quantify the fecal contamination indicators thermotolerant coliforms and enterococci, to then classify the conditions of bathing water quality according with the CONAMA Resolution number 274 of 2000. For the purposes greater knowledge about the health conditions of the Beaches Pirangi and about the influence the PW s waters exert on it, was done parallely to the study of the water quality, an investigation of the sand sanitary quality. Furthermore, it was made an evaluation of the PW s Water Quality through Water Quality Index (WQI). Starting from the results obtained in the research present was possible to verify, among other aspects, that the entry of the PW s waters in the Pirangi beaches exerts direct influence in the bathing water quality of the same ones, being the North Pirangi beach (point tracking PA-02) the most influenced. There was noticed also a significant reduction in the conditions of bathing water quality of the beaches in the rainy season. However, the precariousness do sewerage system of the Natal metropolitan region and the absence of a right system of treatment an final disposal of domestic sewage and industrial are the main factors responsi le for deterioration of the PW s Water Quality, and as a consequence, compromising the bathing water quality of the Pirangi beaches

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The growing accumulation of people in urban centers caused chronic problems of the cities to begin to take an increasingly unsustainable. Primarily related to lack of infrastructure coupled with sanitation and lack of investment in critical sectors such as health, education, housing and transportation, these problems start to deteriorate markedly the quality of life of city dwellers and put into test management policies of the spaces urbanized. To reverse this situation, shows is essential to the use of tools (highlighting this harvest rates and environmental indicators) that help in assessing the current conditions and may assist in predicting future scenarios. From the information listed above, now put the research seeks to present an index called ISBA Environmental (Sanitation Index) which looks at the four urban systems (water, sewer, solid waste and urban drainage) from the viewpoint of application in a geographical cutout specific - in this case the Drainage Basin XII, defined by the Plan of Urban Drainage Stormwater in the city of Natal, capital of Rio Grande do Norte. This index, together with analysis of other factors sought to trace the current conditions of the basin and thus, assist in proposing the best solutions. For the preparation of the index was applied a questionnaire with a sample of 384 (three hundred eighty-four) households that aimed to study two variables: access to services and satisfaction of the population in relation to these. The ISBA has shown that the system is the most deficient collection and disposal of effluents (ICE = 47.66%), followed by the drainage of rainwater (IDAP = 54.17%), water supply (AAI = 61, 36) and solid waste collection (IRS = 78.28). With the ISBA was possible to verify that the qualitative data shows whose subjectivity is evident (as is the case of user satisfaction) can be of great importance when an assessment, since we obtained the correlation coefficient between the variables "Access" and " Satisfaction "equal to 0.8234, showing a strong correlation between the existence / quality of service offered and the impressions of the population that receives them

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The accelerated growth of urban regions have produced relevant effects on water resources. Urban regions need an adequate institutional structure that can be able to face environmental demands and the adverse effects of land use on water resources. This study aims at analysing land use effects on heavy metals concentration in sediments and water, as well as making a comparative analysis involving water physical-chemical parameters. Applied methodology included both in loco water parameters measurement and water and bed sediment sampling at 8 sections along the fluvial system. Sample analysis was performed in laboratory in order to measure heavy metal concentrations. It was measured metal concentrations of Al, Cu, Pb, Cd, Fe, Ni and Zn. Once the samples were subjected to acid digestion (method 3050B), concentration values were measured by using atomic absorption spectrometry by flame (ICP-FLAA). The analysis results were compared with normative reference, these standards is intended to assess the risks of toxic substances in sediment and water management programs. The normative reference used in this work were: a) Ontario Ministry of the Environment and Energy (OMEE, 1993) b) Normative Netherlands (VROM, 2000); c) Normative Canadian (CCME, 1999); d) United States Environmental Protection Agency (USEPA, 1977), e) CONAMA Resolution No. 344/2004; f) CONAMA Resolution No. 357/2005. The high concentrations of iron (38,750 mg.g-1), Lead (1100 mg.g-1), Nickel (100 μg.g-1) and zinc (180 μg.g-1) detected sediments confirm the state of degradation of the aquatic system. Iron concentrations (1.08 mg.L-1), Aluminum (0.6 mg.L-1) and phosphorus (0.05 mg.L-1) present in the water are outside the established standards for human consumption