Remediação de solos contaminados com óleo diesel utilizando um sistema de lavagem com microemulsão

The underground reservoirs of fuel retailing system represent an environmental threat, because once in bad conservation, these tanks allow fuel leakage and infiltration. For soil contaminated with fuel, such as diesel oil, the present study introduces the microemulsion systems used by the method of washing. In tests carried out in column with a sample of sandy soil artificially contaminated and previously characterized as to its void level to porosity, to permeability which is an important parameter concerning the study of the method of washing. While microemulsions were characterized for their viscosity and wettability, a variation of active matter was also done departing from the original formulation. The hydraulic diffusivity of the microemulsion was studied so as the injection of such fluid in a soil with sandy characteristics. The results of the extractions revealed the excellent performance of these systems which get to remove around 95% of diesel fuel. This proves the efficiency of the microemulsion in the process of removal of diesel fuel from the soil with the advantage of being a system easily obtainable and less aggressive to the environment when compared to organic solvents.

Efeito de doses e tipos de compostos orgânicos na produção de alface em dois solos sob ambiente protegido

Avaliou-se o efeito de três doses de composto orgânico de três composições distintas, aplicados em dois solos [Latossolo Vermelho Escuro, textura arenosa (LE) e Areia Quartzoza (AQ)], na produção e absorção de nutrientes pela planta de alface. Conduziu-se de 02/07 a 27/08/1997 um experimento dentro de túnel plástico, pertencente à UNESP, em Botucatu, em vaso plástico, contendo quatro quilos de solo. Os solos foram corrigidos para atingirem saturação por base de 80% e todos os vasos receberam adubação fosfatada (150 mg de P kg-1 de solo), potássica (100 mg de K kg-1 de solo) e micronutrientes. Os compostos foram misturados aos solos nas quantidades de 60; 120 e 240 g de composto por vaso. Os três compostos foram originados a partir de casca de eucalipto, serragem de madeira e palhada de feijão, misturados com esterco de aves. O experimento foi realizado em delineamento inteiramente casualizado, em três repetições, com vinte tratamentos em esquema fatorial (3 doses x 3 compostos x 2 solos) mais um tratamento testemunha para cada solo (ausência de composto orgânico). O composto de palhada de feijão aumentou a biomassa fresca da parte aérea e a quantidade de N, K, Ca, Mg, B, Cu, Fe e Zn nas plantas de alface. Para o P e Mn o composto de palhada de feijão diferiu significativamente apenas em relação ao composto de casca de eucalipto. em todas as características avaliadas no LE houve melhores respostas da cultura em relação ao AQ. Quanto às dosagens utilizadas, as diferenças foram observadas somente nos tratamentos com palhada de feijão, onde as maiores dosagens propiciaram o aumento de biomassa fresca e seca da parte aérea, e nas quantidades de macro e micronutrientes.

Efeito da aplicação foliar de silício em rúcula cultivada em dois tipos de solos

The rocket is a leafy herbaceous annual, features small size, rapid vegetative growth and short life cycle. Silicon is considered a beneficial element, and despite not having his definition of essential mineral nutrition of plants has been widely used in research. The objective was to assess the effect of foliar fertilization with silicon levels in soils in the cultivation of the rocket. The experiment was conducted in a greenhouse in the DRN / Soil Science, UNESP / FCA, Botucatu-SP, from April 15 to May 20, 2008. The experimental design was randomized blocks in factorial 2x5 (two solos and five doses of silicon). At the end of the experiment, evaluated at the point of harvest to plant height (cm), leaf area (LA), total fresh mass (TFM), total dry matter (TDM), leaf area ratio (LAR), specific weight Leaf (PEF), amount of water in the shoot (AWS) and content and accumulation of silicon in the leaves. It was concluded that silicon had no influence on the agronomic characteristics of the rocket and changes were only to soil type.

Variação da qualidade da água do escoamento superficial de duas bacias de drenagem de Natal/RN - Brasil

The urban drainage is one of the powers of environmental sanitation and its scope is the quantitative and qualitative aspects. In decision making of managers and the engineering aspects of design are almost always taken into account only the quantitative aspects. However, the waters of the runoff have the highest concentrations of pollutants at the beginning of precipitation. Thus, if the plot pollution removed, the remaining portion can be used for other purposes. This work has aimed to present the variation of water quality of two drainage basins in the city of Natal / RN-Brazil to support the implementation of drainage to consider the qualitative aspect, and identify potential for the use of water. The basins (M and C) are analyzed closed-type, are in the urban area, are predominantly residential occupation and its waters are used for detention ponds and infiltration. The samples were divided into three phases, the first two direct to final points in a basin and the third in traps distributed over the surface drainage. The parameters had been analyzed were pH, conductivity, dissolved oxygen, Color, Turbidity, COD, Ammonia, nitrite, nitrate, total phosphorus, orthophosphate, Sediments solids, total solids, chloride, sulfate, alkalinity, calcium, magnesium, sodium, potassium, Heavy Metals (Chromium, Cadmium, Lead, Zinc and Copper), Eschichia coli and total coliforms. The parameters studied showed high initial pollution load, events and located in different proportions, except nitrite, heavy metals and biological indicators. The size of the surface drainage and topographic its features influence the quality of water. However, the form of sampling is crucial in the qualitative study in the basin. The samplers developed at work, were generated economic and representative results. The urban rainwater presents organic faecal indicators. The runoff of water from both basins shows no risk of salinity and sodicity for use in irrigation, should be noted the content of chloride in the choice of method of irrigation

Calibração de um equipamento de TDR para medida de umidade de solos

Este estudo visou à obtenção das curvas de calibração de um equipamento de TDR (Time Domain Reflectometry) em cinco solos da região de Piracicaba, SP, e testou a adequação da calibração interna do equipamento e das curvas genéricas de calibração. As curvas ajustadas, em cada solo separadamente, apresentaram coeficientes de determinação (R²) da ordem de 0,99, e a curva ajustada para o conjunto de dados dos cinco solos apresentou R² = 0,976. A análise de erros-padrão de estimativa mostrou que as curvas genéricas não se prestam às aplicações mais sensíveis, tais como na determinação absoluta do conteúdo de água do solo. Os testes de comparação entre as curvas ajustadas, a curva genérica e a curva embutida no equipamento mostraram que a primeira é superior às demais. O estudo mostrou, também, que a curva de calibração embutida no equipamento é inadequada para as determinações de umidade nos cinco solos estudados.

Estudos in silico da proteína AlkB e prospecção de bactérias alcanotróficas em solos da bacia petrolífera potiguar

Some microorganisms from virgin ecosystems are able to use petroleum it as source of carbon and energy. The knowledge of microbial biodiversity can help to reveal new metabolic systems for utilization alkanes with biotechnological importance. The aim of this study is: i) Accomplish an in silico study of the AlkB protein aimed to understand the probable mechanism involved on selectivity of alkanes in Gram positive and Gram negative bactéria. ii) prospect and analyze the response of the microbial alkanotrophics communities in soil and mangrove sediments of BPP RN and soil of Atlantic forest in the Horto Dois Irmãos Reserve area/PE using the molecular biomarker, gene alkB; with the PCR and PCR-DGGE approach

Atributos químicos, produção e qualidade do capim braquiária em solos corrigidos com calcário e escória silicatada

As pastagens constituem a base dos sistemas de produção de bovinos, o que evidencia sua importância e a necessidade de outras práticas de manejo que resultem em maior eficiência desses sistemas. Assim, este trabalho teve como objetivo avaliar os atributos químicos do solo (pH, Ca, Mg e H+Al), o potencial produtivo e a composição química do capim braquiária (Brachiaria decumbens Stapf) em solo corrigido com diferentes doses de calcário e escória silicatada. O experimento foi conduzido em ambiente protegido no período de 2006/2007, na UNESP de Ilha Solteira. Foram testadas cinco doses de calcário e escória silicatada, 0,0; 0,5; 1,0; 1,5; 2,0 vezes a dose recomendada. O delineamento experimental foi inteiramente casualizado, com quatro repetições. Avaliou-se a composição química do solo após incubação dos corretivos, o perfilhamento, a matéria seca, proteína, FDN (fibra em detergente neutro) e FDA (fibra em detergente ácido). Ambos os corretivos proporcionaram ao solo efeito positivo em relação ao pH e teores de cálcio e magnésio. As variáveis matéria seca e FDA não foram influenciadas significativamente pelos tipos e doses de corretivos.

Remediação de solos contaminados com diesel por lavagem com solução de tensoativos

Combating pollution of soils is a challenge that has concerned researchers from different areas and motivated the search for technologies that aim the recovery of degraded soils. Literature shows numerous processes that have been proposed with the intent of remediating soils contaminated by oils and other by-products of the oil industry, considering that the processes available have, generally, high operating costs, this work proposes a costeffective alternative to the treatment of Diesel-contaminated soils. The washing solutions were prepared using water as aqueous phase, the saponified coconut oil (OCS) as surfactant and n-butanol as co-surfactant. In this study, the soil was characterized by physical and chemical analyses. The study of diesel desorption from the soil was held in bath, using hexane and washing solutions, which had 10 and 20 wt.% active matter (AM - co-surfactant/surfactants) respectively. The study of the influence of active matter concentration and temperature in bath agitated used an experimental planning. The experiment also developed a system of percolation in bed to wash the soil and studied the influence of the concentration of active substance and volume of washing solution using an experimental planning. The optimal times to achieve hexane extraction were 30 and 180 min, while the best results using a 10% AM was 60 min and using a 20% AM was 120 min. The results of the experimental planning on bath showed that the maximum diesel removal was obtained when at a 20 wt.% of AM and under 50 °C, removing 99.92% of the oil. As for experiments in the system of percolation soil bed, the maximum diesel removal was high when the volume of the washing solution was of 5 L and the concentration of 20% AM. This experiment concluded that the concentration of AM and the temperature were vital to bath experiments for diesel removal, while in the system of percolation soil bed only concentration of AM influenced the soil remediation

Detecção de metamidofós em solos por métodos ecotoxicológico e cromatografia líquida acoplada à espectrometria de massas sequencial (LC-MS/MS)

Soil contamination by pesticides is an environmental problem that needs to be monitored and avoided. However, the lack of fast, accurate and low cost analytical methods for discovering residual pesticide in complex matrices, such as soil, is a problem still unresolved. This problem needs to be solved before we are able to assess the quality of environmental samples. The intensive use of pesticides has increased since the 60s, because the dependence of their use, causing biological imbalances and promoting resistance and recurrence of high populations of pests and pathogens (upwelling). This has contributed to the appearance of new pests that were previously under natural control. To develop analytical methods that are able to quantify residues pesticide in complex environment. It is still a challenge for many laboratories. The integration of two analytical methods one ecotoxicological and another chemical demonstrates the potential for environmental analysis of methamidophos. The aim of this study was to evaluate an ecotoxicological method as "screening" analytical methamidophos in the soil and perform analytical confirmation in the samples of the concentration of the analyte by chemical method LC-MS/MS In this work we tested two soils: a clayey and sandy, both in contact with the kinetic methamidophos model followed pseudo-second order. The clay soil showed higher absorption of methamidophos and followed the Freundlich model, while the sandy, the Langmuir model. The chemical method was validated LC-MS/MS satisfactory, showing all parameters of linearity, range, precision, accuracy, and sensitivity adequate. In chronic ecotoxicological tests with C. dubia, the NOEC was 4.93 and 3.24 for ng L-1 of methamidophos to elutriate assays of sandy and clay soils, respectively. The method for ecotoxicological levels was more sensitive than LC-MS/MS detection of methamidophos, loamy and sandy soils. However, decreasing the concentration of the standard for analytical methamidophos and adjusting for the validation conditions chemical acquires a limit of quantification (LOQ) in ng L-1, consistent with the provisions of ecotoxicological test. The methods described should be used as an analytical tool for methamidophos in soil, and the ecotoxicological analysis can be used as a "screening" and LC-MS/MS as confirmatory analysis of the analyte molecule, confirming the objectives of this work

Potencialidade à degradação na microbacia Riacho Passagem/RN

A degradação dos recursos naturais é talvez o principal problema da região do semiárido brasileiro, e essa degradação é principalmente resultante das perdas de solo, decorrente do processo erosivo. Na busca de melhor conhecer esta problemática vem sendo empregado o processo de modelagem ambiental, cujo objetivo é identificar e propor soluções para a degradação dos solos. Nesse sentido, o trabalho aplica o modelo da Equação Universal de Perda de Solos (EUPS), desenvolvido nos Estados Unidos ao longo da década de 1950, agregado as ferramentas de geoprocessamento, informações de sensoriamento remoto e Sistemas de Informações Geográficas (SIGs). A área de estudo é a Microbacia Riacho Passagem localizada na região oeste do Estado do Rio Grande do Norte, a microbacia tem uma área de 221,7Km² e esta inserida no semiárido, região Nordeste do Brasil. A metodologia utilizada consiste: em agrupar as variáveis da EUPS no ambiente SIG utilizando imagens de satélite, levantamentos bibliográficos e trabalhos de campo. Para determinação das extensões das vertentes foi empregado o Modelo RAMPA, e para adequar a EUPS as condições da área de estudo, foram realizados ajuste através de modelos estatísticos, aperfeiçoando o trabalho e os resultados gerados pelo modelo. Ao fim do processo foi desenvolvida uma pseudo linguagem no aplicativo Linguagem Espacial para Geoprocessamento Algébrico (LEGAL) disponível no software SPRING versão 5.1.2 servindo de suporte para o processamento das informações contidas no banco de dados, base da EUPS. Os resultados demonstram que inicialmente é necessário delimitar com precisão o período seco e chuvoso, informação fundamental para a EUPS, uma vez que o trabalho busca identificar a perda de solo por erosão hídrica. O modelo RAMPA apresentou-se satisfatório e com elevado potencial de aplicação na determinação dos comprimentos de vertentes utilizando imagens de radar. Quanto ao comportamento das extensões de vertentes, na microbacia, o mesmo apresentou uma pequena variação na porção leste, maiores vertentes, área próxima a desembocadura. Após a aplicação do modelo o valor máximo de perda de solo foi 88 ton/ha.ano com núcleos localizados no NEOSSOLOS LITÓLICOS e o mínimo 0,01 ton/ha.ano localizado no domínio dos LATOSSOLOS e NEOSSOLOS FLÚVICOS. A erosão provoca diminuição do perfil de solo, principalmente nos NEOSSOLOS LITÓLICOS, resultando em alteração no balanço hídrico e conseqüentemente aumento da temperatura do solo, podendo desencadear a desertificação. Os resultados e a metodologia do presente trabalho poderão ser aplicados na busca pelo desenvolvimento sustentável, na região do semiárido brasileiro, auxiliando na compreensão do binômio uso do solo e capacidade de suporte do meio natural.

Caracterização tectono-estratigráfica da sequência transicional na sub-bacia de Sergipe

This thesis deals with the tectonic-stratigraphic evolution of the Transitional Sequence in the Sergipe Sub-basin (the southern segment of the Sergipe-Alagoas Basin, Northeast Brazil), deposited in the time interval of the upper Alagoas/Aptian stage. Sequence boundaries and higher order internal sequences were identified, as well as the structures that affect or control its deposition. This integrated approach aimed to characterize the geodynamic setting and processes active during deposition of the Transitional Sequence, and its relations with the evolutionary tectonic stages recognized in the East Brazilian Margin basins. This subject addresses more general questions discussed in the literature, regarding the evolution from the Rift to the Drift stages, the expression and significance of the breakup unconformity, the relationships between sedimentation and tectonics at extensional settings, as well as the control on subsidence processes during this time interval. The tectonic-stratigraphic analysis of the Transitional Sequence was based on seismic sections and well logs, distributed along the Sergipe Sub-basin (SBSE). Geoseismic sections and seismic facies analysis, stratigraphic profiles and sections, were compiled through the main structural blocks of this sub-basin. These products support the depositional and tectonic-stratigraphic evolutionary models built for this sequence. The structural analysis highlighted similarities in deformation styles and kinematics during deposition of the Rift and Transitional sequences, pointing to continuing lithospheric extensional processes along a NW trend (X strain axis) until the end of deposition of the latter sequence was finished by the end of late Aptian. The late stage of extension/rifting was marked by (i) continuous (or as pulses) fault activity along the basin, controling subsidence and creation of depositional space, thereby characterizing upper crustal thinning and (ii) sagstyle deposition of the Transitional Sequence at a larger scale, reflecting the ductile stretching and thinnning of lower and sub crustal layers combined with an increasing importance of the thermal subsidence regime. Besides the late increments of rift tectonics, the Transitional Sequence is also affected by reactivation of the border faults of SBSE, during and after deposition of the Riachuelo Formation (lower section of the Transgressive Marine Sequence, of Albian age). It is possible that this reactivation reflects (through stress propagation along the newlycreated continental margin) the rifting processes still active further north, between the Alagoas Sub-basin and the Pernambuco-Paraíba Basin. The evaporitic beds of the Transitional Sequence contributed to the development of post-rift structures related to halokinesis and the continental margin collapse, affecting strata of the overlying marine sequences during the Middle Albian to the Maastrichtian, or even the Paleogene time interval. The stratigraphic analysis evidenced 5 depositional sequences of higher order, whose vertical succession indicates an upward increase of the base level, marked by deposition of continental siliciclastic systems overlain by lagunar-evaporitic and restricted marine systems, indicating that the Transitional Sequence was deposited during relative increase of the eustatic sea level. At a 2nd order cycle, the Transitional Sequence may represent the initial deposition of a Transgressive Systems Tract, whose passage to a Marine Transgressive Sequence would also be marked by the drowning of the depositional systems. At a 3rd order cycle, the sequence boundary corresponds to a local unconformity that laterally grades to a widespread correlative conformity. This boundary surface corresponds to a breakup unconformity , being equivalent to the Pre-Albian Unconformity at the SBSE and contrasting with the outstanding Pre-upper Alagoas Unconformity at the base of the Transitional Sequence; the latter is alternatively referred, in the literature, as the breakup unconformity. This Thesis supports the Pre-Albian Unconformity as marker of a major change in the (Rift-Drift) depositional and tectonic setting at SBSE, with equivalent but also diachronous boundary surfaces in other basins of the Atlantic margin. The Pre-upper Alagoas Unconformity developed due to astenosphere uplift (heating under high lithospheric extension rates) and post-dates the last major fault pulse and subsequent extensive block erosion. Later on, the number and net slip of active faults significantly decrease. At deep to ultra deep water basin segments, seaward-dipping reflectors (SDRs) are unconformably overlain by the seismic horizons correlated to the Transitional Sequence. The SDRs volcanic rocks overly (at least in part) continental crust and are tentatively ascribed to melting by adiabatic decompression of the rising astenospheric mantle. Even though being a major feature of SBSE (and possibly of other basins), the Pre-upper Alagoas Unconformity do not correspond to the end of lithospheric extension processes and beginning of seafloor spreading, as shown by the crustal-scale extensional structures that post-date the Transitional Sequence. Based on this whole context, deposition of the Transitional Sequence is better placed at a late interval of the Rift Stage, with the advance of an epicontinental sea over a crustal segment still undergoing extension. Along this segment, sedimentation was controled by a combination of thermal and mechanical subsidence. In continuation, the creation of oceanic lithosphere led to a decline in the mechanical subsidence component, extension was transferred to the mesoceanic ridge and the newly-formed continental margin (and the corresponding Marine Sequence) began to be controlled exclusively by the thermal subsidence component. Classical concepts, multidisciplinary data and new architectural and evolutionary crustal models can be reconciled and better understood under these lines

Avaliação de impacto ambiental e gestão dos recursos natuarias no estuário Apodi Mossoró, nordeste do Brasil

The aim of this study is to investigate the eco-environmental vulnerability, its changes, and its causes to develop a management system for application of eco-environmental vulnerability and risk assessment in the Apodi-Mossory estuary, Northeast Brazil. This analysis is focused on the interference of the landscape conditions, and its changes, due to the following factors: the oil and natural gas industry, tropical fruits industry, shrimp farms, marine salt industry, occupation of the sensitive areas; demand for land, vegetation degradation, siltation in rivers, severe flooding, sea level rise (SLR), coastal dynamics, low and flat topography, high ecological value and tourism in the region and the rapid growth of urbanization. Conventional and remote sensing data were analyzed using modeling techniques based on ArcGIS, ER-Mapper, ERDAS Imagine and ENVI software. Digital images were initially processed by Principal Component Analysis and transformation of the maximum fraction of noise, and then all bands were normalized to reduce errors caused by bands of different sizes. They were integrated in a Geographic Information System analysis to detect changes, to generate digital elevation models, geomorphic indices and other variables of the study area. A three band color combination of multispectral bands was used to monitor changes of land and vegetation cover from 1986 to 2009. This task also included the analysis of various secondary data, such as field data, socioeconomic data, environmental data and prospects growth. The main objective of this study was to improve our understanding of eco-environmental vulnerability and risk assessment; it´s causes basically show the intensity, its distribution and human-environment effect on the ecosystem, and identify the high and low sensitive areas and area of inundation due to future SLR, and the loss of land due to coastal erosion in the Apodi-Mossoró estuary in order to establish a strategy for sustainable land use. The developed model includes some basic factors such as geology, geomorphology, soils, land use / land cover, vegetation cover, slope, topography and hydrology. The numerical results indicate that 9.86% of total study area was under very high vulnerability, 29.12% high vulnerability, 52.90% moderate vulnerability and 2.23% were in the category of very low vulnerability. The analysis indicates that 216.1 km² and 362.8 km² area flooded on 1m and 10m in sea levels respectively. The sectors most affected were residential, industrial and recreational areas, agricultural land, and ecosystems of high environmental sensitivity. The results showed that changes in eco-environmental vulnerability have a significant impact on the sustainable development of the RN state, since the indicator is a function of sensitivity, exposure and status in relation to a level of damage. The model were presented as a tool to assist in indexing vulnerability in order to optimize actions and assess the implications of decisions makers and policies regarding the management of coastal and estuarine areas. In this context aspects such as population growth, degradation of vegetation, land use / land cover, amount and type of industrialization, SLR and government policies for environmental protection were considered the main factors that affect the eco-environmental changes over the last three decades in the Apodi-Mossoró estuary.

Análise de risco à erosão costeira na região de Tibau do Sul/RN através de mapeamento geoambiental e análise morfodinâmica

The research area is located on the county of Tibau do Sul, in the east coast of Rio Grande do Norte State, about 80km south of the capital Natal. The tourism represents the main income activity and Pipa beach is the most visited beach in the city, annually receives a large influx of domestic and foreign tourists. Some recent studies have reported the occurrence of coastal erosion in this littoral, being the main objective of the research, analyze the existing coastal erosion, through two methodologies, the geoenvironmental mapping and beach morphodynamics. The geoenvironmental mapping was done from oblique aerial photographs and field visits, which sought to carry out first the geomorphological mapping, with the purpose of analyzing features that suggest susceptible areas to erosion, as areas without protection of natural dunes, marine terraces, or sandstones (beach-rocks and ferruginous sandstones), areas with the presence of gullies and stretches where the sea-cliffs were in direct contact with the action of the sea, representing the beginning of the beach profile. In the morphodynamic study sought to carry out the survey of the physical and morphological characteristics, the analysis of sediment grain of the beaches and finally the analysis of the morphodynamic parameters to generate a table of risk to erosion by sector of the beach. The morphodynamic parameters were defined by the methodology proposed by Short (2006), in which considers different patterns of dynamism on beaches with characteristics favorable and unfavorable to erosive profiles. The maps indicated different levels of risk to the segments of the beaches analyzed, suggesting risk to erosion low and low to moderate only in areas north and northwest of the beaches of Madeiro and Curral, and levels of moderate and high risk sectors in the south and southeast of these beaches . The beach of Pipa showed moderate levels of risk and moderate to high at the ends and high risk to erosion in the central portion. The study of the coastal environment, its morphological evolution, and areas with problems of erosion, are of fundamental importance to assist coastal management policies, giving grants for planning activities undertaken in these regions

Evolução estrutural e termocronológica meso-cenozóica da Zona de Cisalhamento Portalegre, Nordeste do Brasil

The Portalegre shear zone (ZCPa), which is located in the Rio Grande do Norte and Paraíba states (Northeastern Brazil), is na important right-lateral, northeast-trending lineament formed during the Brazilian Orogenic Cicle). The ZCPa experienced na important brittle reactivation from the Mesozoic until the present. This reactivation led to the formation of the Gangorra, Pau dos Ferros, Coronel João Pessoa, Icozinho and Rio do Peixe basins. The reactivation northern parto f the ZCPa that marks the boundary of the Potiguar Basin is denominated Carnaubais Fault. Several fracture patterns were mapped along the ZCPa. Samples were collected in Neoproterozoic granite outcrops, along the ZCPa. These samples yielded AFT ages from 86±13 to 376±57 Ma, and the mean track length from 10.9±0.8 to 12.9±1.5 mm. Samples from the East block yielded mean ages of 103 Ma, mean track lengtn 12,1mm, and mean altitude 250m, whereas samples from West block yielded mean ages of 150 Ma, which reach 345 Ma and 220 Ma in the Pau dos Ferros and Coronel João Pessoa basins, respectively. Thermal history models were sorted out for each crustal block. Samples from West block recorded a thermal history from Carboniferous Period until the Permiano, when the block experienced gradual uplift until the Cretaceous, when it underwent downfaulting and heating until the Tertiary, and it eventually experienced a rapid uplift movement until recent times. Samples from the East block presented the same cooling and heating events, but at they occurred different times. The East block thermal record started ~140 Ma, when this block experienced cooling until ~75 Ma. Both blocks show a denundacion/erosional history more similar in the Tertiary. The AFT data indicate an important tectonic event ~140 Ma, when the West block experienced downfaulting and the East block experienced uplift. This tectonic process led to the generation of several sedimentary basins in the region, including the Potiguar basin. This tectonic event is also interpreted as a rift process caused by an E-W-trending extension. It the Tertiary, some heating events can be tentatively attributed to the macau volcanic event

A erosão costeira e sua influência sobre a atividade petrolífera: alternativas sustentáveis na mitigação de impactos ambientais

The study area consist in high sensitivity environments located on the northern coast of Rio Grande do Norte, Northeast Brazil. The barrier island are the main geomorphological features on the coastal landscape, being naturally instable and surrounded by industrial activities like oil fields, salt industry, shrimp farms and urban areas sometimes installed parallel to the coast, combined with coast engineering interventions. High energy hydrodynamic process are responsible for the morphological instability of the coast. The study was based on remote sensing data obtained between 1954 and 2007 which consist in orbital images from Landsat, CBERS and Ikonos satellites and aerial photos. With all data integrated on GIS environment it was possible to update thematic maps of geology, geomorphology, vegetation, soil and landuse and development of multitemporal maps pointing areas with erosion and depositions of sediments, defining the critical erosion process on this region. The bigger morphological changes are related to changes on wind patterns during the year, terrestrial and sea breezes during the day, with spits and barrier island migration, opening and closing of channels like the one parallel to the coast on the area of Serra and Macau oil fields. These factors combined with the significant reduction on sediment budgets due to the loss of natural spaces to sediment reworking contribute to the low resilience which tends to be growing on the area of Serra and Macau oil fields. In front of such scenery a detailed monitoring was done in order to find technological possibilities for coastal restoration. A pilot area was defined to start the project of mangrove restore together with beach nourishment in order to minimize the effect of the erosion caused by the channel parallel to the coast, contributing to stabilize the northeast channel as the main one. It s expected that such methodology will aid the coastal environments restoration and the balance between industrial activities and coastal erosion