Uso do gpr na caracterização da pluma de contaminação gerada por hidrocarbonetos a partir de um posto de combustível na praia de Búzios/RN

This work is the application of geophysical methods, using the Ground Penetrating Radar (GPR), with the objective of survey in a subsurface plume of contamination caused by a disabled gas station. The gas station is located on the Búzios beach in southern coast of the state to Rio Grande do Norte in an Area of Environmental Protection called Bonfim-Guaraíra. The interest to develop this work was the presence of contaminants (hydrocarbons) in a well located on the desktop, previously used for the abstraction of groundwater for residents living near the site. Were raised 15 geophysical survey lines totaling 775,48 lifting and installed 4 piezometer, to confirm the contamination and prepare a pluviometric map that helped in indicating the direction of local groundwater flow, thus showing the direction of movement of the probably plume of contamination. From the processing of the GPR lines was possible to identify two likely phases of contamination according to the classification proposed by Azambuja et al 2000, which are called phase absorbed and dissolved phase

Caracterização Morfodinâmica e Sedimentologia da Plataforma Continental Rasa na APA Estadual dos Recifes de Corais - RN

This study had to aimed to characterize the sediments of shallow continental shelf and realize the mapping of features visible for satellite images by using remote sensing techniques, digital image processing and analysis of bathymetry between Maxaranguape and Touros - RN. The study s area is located in the continental shallow shelf of Rio Grande do Norte, Brazil, and is part of the Environmental Protection Area (APA) of Coral Reefs. A total of 1186 sediment samples were collected using a dredge type van veen and positioning of the vessel was made out with the aid of a Garmin 520s. The samples were treated In the laboratory to analyze particle size of the sediment, concentration of calcium carbonate and biogenic composition. The digital images from the Landsat-5 TM were used to mapping of features. This stage was used the band 1 (0,45-1,52 μm) where the image were georeferenced, and then adjusting the histogram, giving a better view of feature bottom and contacts between different types of bottom. The results obtained from analysis of the sediment showed that the sediments of the continental shelf east of RN have a dominance of carbonate facies and a sand-gravelly bottom because the region is dominated by biogenic sediments, that are made mainly of calcareous algae. The bedform types identified and morphological features found were validated by bathymetric data and sediment samples examined. From the results obtained a division for the shelf under study is suggested, these regions being subdivided, in well characterized: (1) Turbid Zone, (2) Coral Patch Reefs Zone, (3) Mixed Sediments Carbonates Zone, ( 4) Algae Fouling Zone, (5) Alignment Rocky Zone, (6) Sand Waves Field (7) Deposit siliciclastic sands

Caracterização geomorfológica e modelagem de dados espaciais na plataforma continental rasa do RN nos limites da folha Touros

This work focuses the geomorphological characterization and spatial data modeling in the shallow continental shelf within the Folha Touros limits (SB-25-CV-II), based on bathymetric data analysis and remote sensing products interpretation. The Rio Grande do Norte state is located in northeastern Brazil and the work area is located at the transition region between the eastern and northern portions of their coast. The bathymetric surveys were conduced between march and may 2009, using a 10 meters long vessel and 0.70 meters draught, equipped with global positioning system and echo sounder (dual beam, 200KHz , 14°). The fieldwork resulted in 44 bathymetric profiles espaced 1.5 km and 30 km average length. The bathymetric data amount were 111,200 points and were navigated 1395.7 km within na area about 1,850 km2. The bathymetric data were corrected for the tide level, vessel draught and were subsequently entered into a geographic information system for further processing. Analysis of remote sensing products was carried out using Landsat 7/ETM + band 1, from november 1999. The image was used for visualization and mapping submerged features. The results showed the presence of geomorphological features within the study area. Were observed, from the analysis of local bathymetry and satellite image, seven types of geomorphological features. The channels, with two longitudinals channels (e. g. San Roque and Cioba channels) and other perpendicular to the coast (e. g. Touros, Pititinga and Barretas). Coastal reef formations (Maracajaú, Rio do Fogo and Cioba). Longitudinal waves, described in the literature as longitudinal dunes. The occurrence of a transverse dune field. Another feature observed was the oceanic reefs, an rock alignment parallel to the coast. Were identified four riscas , from north to south: risca do Liso, Gameleira, Zumbi, Pititinga (the latter being described for the first time). Finally, an oceanic terrace was observed in the deepest area of study. Image interpretation corroborated with the in situ results, enabling visualization and description for all features in the region. The results were analysed in an integrating method (using the diferent methodologies applied in this work) and it was essential to describe all features in the area. This method allowed us to evaluate which methods generated better results to describe certain features. From these results was possible to prove the existence of submerged features in the eastern shallow continental shelf of Rio Grande do Norte. In this way, the conclusions was (1) this study contributed to the provision of new information about the area in question, particularly with regard to data collection in situ depths, (2) the method of data collection and interpretation proves to be effective because, through this, it was possible to visualize and interpret the features present in the study area and (3) the interpretation and discussion of results in an integrated method, using different methodologies, can provide better results

Caracterização morfológica e sedimentar do talude continental (foz do Amazonas)

Created on 3 december 1997, the REMPLAC (Program for Assessment of Mineral Potencial of the Continental Shelf), this porgram aimed to make the basic survey, systematic geological and geophysical continental shelf, detail, at an appropriate scale, sites geo-economic, and perform the analysis and evaluation of mineral deposits. The REMPLAC should continue the efforts of Global Recognition Program of the Brazilian Continental Margin REMAC closed in 1978, the operations Geophysical Sea (GEOMAR) developed by the Directorate of Hydrography and Navigation and the various initiatives of the Program of Marine Geology and Geophysics (PGGM). Despite the high interest on the Amazon platform, there is little information o their morphology and sediment characterization, and in order to fill this gap, the present work samples sedimentological point followed by seismic acquisition. And the studies were to characterize the possible area of interest as being directly influence by tides, which sediments are reworked throughout the platform featuring grain angle with sharp corners, and the carbonate content increases as it approaches the breakdown the platform, and the bodies found outside the foraminifera and mollusks. However, diverging with organic matter that reduces its concentration as it moves away from the coast. The seismic profiles do not get satisfactory results because of low visibility, however, to correlate with the spot samples, of sediment were possible morphological characterization of the area.

Caracterização multi-escalar de bandas de deformação nas tectonossequências paleozóica, pré- e sin-rifte da Bacia do Araripe, Nordeste do Brasil

Deformation bands are structures, developed in porous sandstones, that has small offsets and they are not shown on seismic section. The deformation bands of the pre and synrift sandstones of Araripe Basin were studied in outcrop, macroscopic and microscopic scales. The hierarchical, cinematic and spatial-geometric characteristics, and also the deformational mechanisms acting during its structural evolution were established too. In general, the mesoscopic scale observation allowed to discriminate deformation bands as singles or clusters in three main sets: NNE-SSW dextral; NE-SW normal (sometimes with strike-slip offset); and E-W sinistral; further a bed-parallel deformation bands as a local set. The microscopic characterization allowed to recognize the shearing and cataclastic character of such structures. Through the multi-scale study done in this work we verified that deformation bands analyzed were preferentially developed when sandstones under advanced stage of lithification. We also infer that the geometrical-spatial complexity of these bands, together with the presence of cataclastic matrix, can difficult the migration of fluids in reservoir rocks, resulting on their compartmentalization. Therefore, the study of deformation bands can aid researches about the structural evolution of sedimentary basin, as well as collaborate to understand the hydrodynamic behavior of reservoirs compartmented by these deformational structures

Caracterização de reservatórios siliciclásticos neoaptianos: um estudo do membro carmópolis no campo de Camorim, sub-bacia de Sergipe, Brasil

The Camorim Oilfield, discovered in 1970 in the shallow water domain of the Sergipe Sub-basin, produces hydrocarbons from the Carmópolis Member of the Muribeca Formation, the main reservoir interval, interpreted as siliciclastics deposited in an alluvial-fluvial-deltaic context during a late rifting phase of Neoaptian age, in the Sergipe-Alagoas Basin. The structural setting of the field defines different production blocks, being associated to the evolution of the Atalaia High during the rift stage and subsequent reactivations, encompassing NE-SW trending major normal faults and NWEW trending secondary faults. The complexity of this field is related to the strong facies variation due to the interaction between continental and coastal depositional environments, coupled with strata juxtaposition along fault blocks. This study aims to geologically characterize its reservoirs, to provide new insights to well drilling locations in order to increase the recovery factor of the field. Facies analysis based on drill cores and geophysical logs and the 3D interpretation of a seismic volume, provide a high resolution stratigraphic analysis approach to be applied in this geodynamic transitional context between the rift and drift evolutionary stages of the basin. The objective was to define spatial and time relations between production zones and the preferential directions of fluid flow, using isochore maps that represent the external geometry of the deposits and facies distribution maps to characterize the internal heterogeneities of these intervals, identified in a 4th order stratigraphic zoning. This work methodology, integrated in a 3D geological modelling process, will help to optimize well drilling and hydrocarbons production. This methodology may be applied in other reservoirs in tectonic and depositional contexts similar to the one observed at Camorim, for example, the oil fields in the Aracaju High, Sergipe Sub-basin, which together represent the largest volume of oil in place in onshore Brazilian basins

Caracterização geológica, geoquímica e geocronológica da suíte plutônica enoproterozóica da região de Serrinha, porção centro-leste do maciço São José de Campestre, sudeste do RN

The of Serrinha plutonic suite, northeastern portion of the Borborema Province (NE Brazil), is characterized by a voluminous and diversified magmatism of Neoproterozoic age, intrusive in the Archean to Paleoproterozoic gneissic-migmatitic basement of the São José de Campestre massif. Field relations and petrographic and geochemical data allowed us to individualize different lithologic types among this plutonic suite, which is represented by intermediate to mafic enclaves, porphyritic diorites, porphyritic granitoids, porphyritic granodiorites, microporphyritic granites and dykes/sheets of microgranite. The intermediate-to-mafic enclaves occur associated with porphyritic granitoids, showing mixture textures. The porphyrytic diorites occur as isolated bodies, generally associated with intermediate-to-mafic enclaves and locally as enclaves within porphyritic granites. The granodiorites represent mixing between an intermediate to mafic magma with an acidic one. The micropophyritic granites occur as isolated small bodies, generally deformed, while the microgranite dykes/sheets crosscut all the previous granitoids. A U-Pb zircon age of 576 + 3 Ma was obtained for the Serrinha granite. This age is interpreted as age of the peak of the regional ductile deformational event (D3) and of the associated the E-W Rio Jacu shear zone, which control the emplacement of the Neoproterozoic syntectonic plutons. The porphyrytic granitoids show monzogranitic composition, transitional between peraluminous and metaluminous types, typically of the high potassium subalkaline-calc-alkaline series. The intermediate-to-mafic enclaves present vary from quartz diorite to tonalite/granodiorite, with metaluminous, shoshonitic affinity. The diorites are generally quartz-monzodiorite in composition, with metaluminous, subalkaline affinity. They display coarse-grained, inequigranular, porphyrytic texture, with predominance of plagioclase phenocrystals immersed in a matrix composed of biotite and pyroxenes. The microporphyrytic granites are essentially monzogranites of fine- to medium-grained texture, whereas microgranite dikes/sheets varying from monzogranites to syenogranites, with fine to media texture, equigranular. The diversified magmatism occurring at a relatively small surface associated with shear zones, suggests lithospheric dimensions for such structures, with magma extractions from different depths within the lower crust and upper mantle. The geological, geochemical and geochronological characteristics of the Serrinha plutonic suite suggest a pos-collisional geodynamic context for the Neoproterozoic magmatism. Thermobarometric data show emplacement conditions in the range 5-6 kbar (AlTamphibole) and 730-740°C (plagioclase-amphibole) for the porphyrytic granitoids (Serrinha body) and the intermediate-to-mafic enclaves

Caracterização e análise do talude continental adjacente à bacia potiguar, NE Brasil

This work presents the results of the first imaging of continental slope adjacent to Potiguar Basin, in the equatorial Brazilian margin (NE Brazil). Swath bathymetry provided a complete coverage of seafloor between the upper and middle slope (100-1,300 m). Fifteen submarine canyons were mapped. The shape of the slope reflects in distinct spatial distribution of the canyons. The western area displays convex profiles which implied a greater amount of incisions by canyons. Some of them have gradient walls higher than 35°. They were classified according to location and morphology. The canyons with heads indenting shelf edge, association with a incised valley and a large fluvial system, high sinuosities, V shape, terraces along margins, further erosive features such as landslide and gullies allow to deduce a sandy-gravelly sedimentation. These canyons are associated with deposition of submarine fan systems that have been considered permeable hydrocarbon reservoirs. The presence of gullies, furrows and dunes demonstrates the role of bottom currents in the shaping of the slope. The enlargement of canyons and the change in the course when they cross the border fault imply that tectonic has also influenced in the morphology of deep waters environments of Potiguar Basin. The current sedimentation of continental slope is considered mixed because the sediments are composed of siliciclastics and bioclasts. Predominant siliciclastics are calcite, dolomite, quartz, and clay minerals. The presence of stable minerals (zircon, tourmaline and rutile), and fragmented bioclasts implies the contributions of Rivers Açu and Apodi

Gerenciamento ambiental das fazendas de camarão do Rio Grande do Norte

The present dissertação had as objective to study the ambient management in the Farms Saint Rita, Tahim Agropesca and Agropesca Rigomoleiro, in the Great River of the North. For this we use as theoretical tool some fundantes concepts of geographic science, the space, and as concepts auxiliary of ambient management, of estuaries as the half natural one and of manguezais as ecosystem. The study if it gave taking in consideration a model of flow of activities of a typical farm following the way of the residues produced since the beginning until its final destination, in a suitable script of SCHERER (1999). The considered flow established a sequence activities where it is identified the material of entrance, the process of management, the residues of exit and the destination of the residues to the long one of the phase of culture of the shrimp. From it was there had been elaborated a series of managemental pictures with the data raised in the three farms, of different transports and concludes that the ambient management of these farms does not follow the formal standards of a system of typical ambient management. Collating with the system of considered by norm ISO14000 the study it disclosed that all the companies are in a situation of not conformity and that the impacts on the environment continue being many significant ones. However, it is possible to implant norm ISO14000 because some procedures implanted for the farms are correct of the point of view of the ambient management

Fragilidade ambiental da bacia hidrográfica do Rio Punaú (RN) e área litorânea adjacente

Hydrographic basins always exercised a big fascination over humankind that attracted for its scenery beauty or for its richness in natural resources, had been acting in order to modify these important ecosystems without, therefore, considering the possible consequences of these changes. The attributed importance to the coast ecosystems, in eminence to the hydrographic basin of Punaú river and adjacent areas, is had when it s verified the diversity of the ecosystems that contemplate it. Hydrographic basin in evidence in Rio Grande do Norte state, occupies an area of nearly 652.71 km², being it sited in the homogeneous micro-region Litoral Nordeste, with a regional population estimated in nearly 75,188 inhabitants, according to the Anuário Estatístico do Rio Grande do Norte 2004. The region of the researched basin is formed by seven municipal districts related as it follows: Maxaranguape, Pedra Grande, Pureza, Rio do Fogo, São Miguel de Touros, Taipu and Touros, but Maxaranguape, Rio do Fogo, Touros and Pureza have a direct participation in the basin. Basin in study have it lands evaluated according to the agriculturist aptitude by the conventionally methodology practiced in the country, having as objective, then, a compara-tive analysis between the ambient unities, Aeolian littoral and coast tray, identified in the researched area. From the characterization of the physic way of the area in study and owning the kept data, it was proceeded the integrated analysis of the structural elements of the landscape which were evidenced that the fragile areas are associated with the areas of agriculture cultivation, such as the ones of irregular occupation. About the degradation, the ambient diagnostic of the basin indicated that the equivalent to the Aeolian Littoral Ambient Unit correspond to the bigger pledging of the ambient quality, in other words, high ambient fragility, being this result due to the use and occupation of the soil, propitiating this way, vulnerability in the vegetal cover of the area, despite it disposes of a low agriculture cultivation percentage. Already in the Coast Ambient Tray, is emphasized the medium ambient fragility, despite of the high index of cultivated area. In a general way, the total area of the hydrographic basin of Punaú river and adjacent areas presented ambient impacts over the tolerance limit, indicating the necessity of a review of the practices of use and handling of the soil, reforesting of the water courses edges, control of erosion and contamination of the aqueous in the perspective to reduce the effects of the impacts due to the use and occupation of the basin in regard. The present search evaluated the ambient impacts diagnosised in the hydrographic basin of Punaú river and adjacent areas, pointing the causes and the probable consequences of the damages caused by these impacts to the basin ambient. From the analysis of these data, if was possible to become explicit how they are fundamental as key elements in the process of decision taking in the ambient questions