15 resultados para 260114 Geomorphology

em Universidade Federal do Rio Grande do Norte(UFRN)


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The accelerated pressure of use and occupation of Rio Grande do Norte coastline in the last two decades presented the tourism as its main vector, having as a consequence a strong, articulated and growing real estate speculation of this area. In the Natal County there is a Zona Especial de Interesse Turistico II (Special Zone of Tourism Interest II) (ZET-II), consisted of urban beaches with approximately 8.5 km that is an important seashore of the city. The purpose of this research was identification, characterization and assessment of the process of use and occupation of dunes fields emphasizing the role of ZET-II, whereas the specific goals was the analysis of weather, geology and geomorphology, characterization of use and occupation of soil, and elaboration of an environmental diagnosis with identification and description of its mains consequences. The result of this work was the delineation of geologic-geomorphological map of the area with identification of principals units, determining its use and occupation, the measurement of the area already occupied by equipments, besides the description of the environmental impacts on dune fields: devastation, coastline erosion, ocean pollution by sewer and pluvial waters, contamination of groundwater, distribution inadequate of solid residues, landscape degradation, and occupation of seashore through the privatization of public areas. Concluding that the degrading changes occurred in this areas are resulting from the nature of use and urban seashore regulations, which have been diminishing the natural aspect, altering the landscape definitely, compromising the quality of hydro resources and altering its use, privatizing the areas between tides, complicating the population access and obstructing the scenery visualization of dunes and ocean. There is an urgent necessity of improvement of public politics in order to improve the strategies and organization of use and occupation of space urban-coastline

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Provide data and information on watershed becomes important since the knowledge of their physical characteristics, land use, etcetera, allows for better planning and sustainable use of economically, socially and environmentally in this area. The investigation of the physical environment has been commonly given with the use of geoprocessing, which has proved a very efficient tool. Within this context, this research aims at analyzing the river basin Punaú (located in the cities of Touros, Rio do Fogo and Pureza, state of Rio Grande do Norte) in several aspects, using geoprocessing as a tool of work, to provide information about the entire watershed. Specifically, this study aimed to update pre-existing maps, such as geological, geomorphological and land use, generating map of environmental vulnerability, under the aspect of erosion susceptibility of the area, generating map of legal incompatibility, identifying areas that are already being employed in breach of environmental legislation; propose solutions to the occupation of the river basin Punaú, focused on environmental planning. The methodology was based on the use of geoprocessing tools for data analysis and to make maps of legal incompatibility and environmental vulnerability. For the first map was taken into account the environmental legislation regarding the protection of watersheds. For the vulnerability analysis, the generated map was the result of crossing the maps of geology, geomorphology, soils and land use, having been assigned weights to different attributes of thematic maps, generating a map of environmental vulnerability in relation to susceptibility to erosion. The analysis results indicate that agriculture is the most significant activity in the basin, in total occupied area, which confers a high degree of environmental vulnerability in most of the basin, and some agricultural areas eventually develop in a manner inconsistent with Brazilian environmental legislation. It is proposed to consider deploying a measure of revitalization of the watershed in more critical areas and conservation through mitigation measures on the causes of environmental degradation, such as protection of water sources, protection and restoration of riparian vegetation, protection of permanent preservation areas, containment of erosion processes in general, and others listed or not in specific laws, and even the establishment of a committee of basins in the area

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The physical and environmental factors presented by each habitat and the rhythm of behavior patterns strongly influence the ecology and behavior of the all living beings. At same time this factors may provide clues about the structure of a population and its ecological balance. The organizational structure, ecology and behavior of a species appraised in a region if we know be in balance when compared to the same type of appraisal made in a degraded area can provide a clear view of how the anthropogenic influences acted on these species and what steps can be taken in order to mitigate the effects and keep the population. The region where this study was conducted is, like most areas of port, subject to intense physical and environmental degradation. With the emerging interest of change in the quality of these environments also by the companies themselves that use the port services, the proposed study aimed to characterize the use of habitat, the distribution of behavioral activities carried out throughout the day and influence of geomorphology of the bed, depth and variation of tide on the expression of the behavior of Sotalia guianensis in the port of Maceio - Alagoas. From this information will be possible establish parameters for comparison with other populations of S. guianensis and establish conservation measures for the population occurring in the port of Maceio - AL, serving also as a basis for conservation actions future performed in other port regions

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The semi-arid Northeast region are coming through changes since its formation causing changes in the landscape and increased degradation. The economic dynamics which was established at the Potiguar semiarid had for a long time settled in livestock, subsistence agriculture and cotton, however, these economies decline from the year 1970. Thus, the Potiguar spaces are undergoing by a process of space reordering marked by the growth of agricultural activities and the process of urbanization. In the Potiguar western region these changes weaken significantly transform the landscape. In these areas, the process of urbanization and agricultural activities have caused changes in the hinterland landscape changing the natural dynamics of the caatinga biome that has been subject to negative interference with the indiscriminate removal of vegetation. In this case, the specific study area of the watershed of Cajazeiras Creek located in the cities of Pau dos Ferros, Água Nova, Encanto and Rafael Fernandes, changes in the landscape has led to degradation and environmental fragility. From this perspective, the research objective is to assess the dynamics of the landscape of the watershed of Cajazeiras Creek, semiarid region of the state of Rio Grande do Norte, identifying the degrading factors, the most degraded areas and/or susceptible to degradation and environmental fragility. The research investigated the phenomena of light geosystems theory that emphasizes the integration of elements in shaping the landscape. During this reporting period, it was carried out exploratory and bibliographical research, and geoprocessing techniques to assess the social and environmental conditions of the researched area and its environmental fragility. To do so, first, it was made an multitemporal analisis on the basis of the years 1984, 1996 and 2009 demonstrating that the dynamics of use and land cover in the watershed of Cajazeiras Creek showed a significant change in the landscape, especially in the caatinga vegetation. This has been recovering in various areas of the watershed, especially in its upper course in the mountains of Bom Sera, in Encanto city. The analysis showed the need to develop policies and programs for the maintenance, restoration and preservation of the caatinga vegetation of the river network and of water bodies. In addition, it was identified the most degraded areas of the watershed, environmental fragility and potential emerging that take into account the landscape components such as climate, topography, geology, pedology, geomorphology and the use and occupation of the soil in an integrated manner. The results show that the landscape of the watershed has medium and high environmental fragility throughout its area, especially on the banks of the river network provided by the use and occupation of the soil in an inadequate way with the environmental conditions of the watershed

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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.

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Numerous studies have indicated that the Potiguar Basin is affected by Cenozoic tectonics. The reactivation of Cretaceous fault systems affect the post-rift units, witch include Neogene and overlying Quaternary sediments. In this context, the objectives of this thesis are the followings: (1) to characterize the effects of post-rift tectonics in the morphology of Apodi Mossoró-river valley located in the central portion of the Potiguar, (2) to characterize the drainage of the Apodi Mossoró river valley and investigate the behavior of their channels across active faults, and (3) to propose a geologic-geomorphological evolutionary model for the study area. This study used a geological and geomorphological mapping of the central part of the basin, with emphasis on the Quaternary record, luminescence dating of sediments, and geoelectric profiles of the area. The results reveal by maps of structural lineaments and drainage channels of the rivers form valleys that are affected by faults and folds. In Apodi-Mossoró valley, anomalies of channel morphology are associated with the deformation of the post-rift basin. These anomalies show the reactivation of major fault systems in the Potiguar Basin in Cenozoic. On a regional scale, can be seen through the vertical electric profiles that the Cenozoic tectonics is responsible for the elevation of a macro dome NE-SE-trending 70-km long and 50km wide and up to 270 above sea level. In this sector, the vertical electric profiles data show that the contact between the Cretaceous and Neogene rise more than 100m. This Is an important feature of inversion data obtained in this work showed that the deposits that cover the macro dome (Serra do Mel) have ages of 119 ka to 43 ka. In the river valley and surrounding areas Apodi-Mossoró ages vary between 319 ka and 2.7 ka. From these data it was possible to establish the correct geochronological posiconamento paleodepósitos of distinguishing them from the fluvial deposits of the Neogene (Barreiras Formation)

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This paper presents models of parameters of Sea Surface Layer (SSL), such as chlorophyll-a, sea surface temperature (SST), Primary Productivity (PP) and Total Suspended Matter (TSM) for the region adjacent to the continental shelf of Rio Grande do Norte (RN), Brazil. Concentrations of these parameters measured in situ were compared in time quasi-synchronous with images AQUA-MODIS between the years 2003 to 2011. Determination coefficients between samples in situ and bands reflectance sensor AQUA-MODIS were representative. From that, concentrations of SSL parameters were acquired for the continental shelf of the RN (eastern and northern) analyzing the geographic distribution of variation of these parameters between the years 2009-2012. Geographical and seasonal variations mainly influenced by global climate phenomena such as El Niño and La Niña, were found through the analysis of AQUA-MODIS images by Principal Components Analysis (PCA). Images show qualitatively the variance and availability of TSM in the regions, as well as their relationship with coastal erosion hotspots, monitored along the coast of the RN. In one of the areas identified as being of limited availability of TSM, we developed a methodology for assessment and evaluation of Digital Elevation Models (DEM) of beach surfaces (emerged and submerged sections) from the integration of topographic and bathymetric data measured in situ and accurately georeferenced compatible to studies of geomorphology and coastal dynamics of short duration. The methodology consisted of surveys with GNSS positioning operated in cinematic relative mode involved in topographic and bathymetric executed in relation to the stations of the geodetic network of the study area, which provided geodetic link to the Brazilian Geodetic System (GBS), univocal , fixed, and relatively stable over time. In this study Ponta Negra Beach, Natal / RN, was identified as a region with low variance and availability of MPS in the region off, as characterized by intense human occupation and intense coastal erosion in recent decades, which presents potential of the proposed methodology for accuracy and productivity, and the progress achieved in relation to the classical methods of surveying beach profiles

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The study area islocated in the northern cost of Rio Grande do Norte State, preciselyin a west zone of Apodi-Mossoró River, inclunding Tibau City, Grossos City and part of Mossoró City. Geologicaly, this area is composed by rokcs of Potiguar basin, represented by Cretaceous, Tertiary and Quaternary sediments. This area is characterizer by the intense action of cosatal processes (eolic and costal tranports, generalized erosion, alteration in the sediments balance and coast modification), reponsable for it´s morfological instability, also the antropic interference, where the iol industry is located, next Mossoró City, and also the salt exploration industry and the tendency of expantion of shrimp cultivation. This report had as objective the multitemporalgeoenvorimentalmonitoring of the region by recognizingin the field and analizingimages of orbital sensors of diferents years of last four decades. This analisys was achieved by Digital Images Procesing (DIP) thecnics, com subsidized, in a GIS, the preparion of Thematic Maps of natural resources (Geology, Geomorphology and Use & Ocupatios of Earth) and the Envorimental Sensivity to Oil Spilling, main objective os this project. Such technics constitute important tools of envoriment monitoring and maneging, indicating tendencies of antropic of natural growing, making possible the apropiated planning of development of the region, where the steps can be indicated minimized possibles envorimental impacts caused by antropics interferencies on the region, mainly those related to industrial activities, and oil industry above all. Researchs of this nature are very important to the analisys and ordered manegements of use and ocupation of coastal places

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The North Paraíba River Estuary, located in the eastern portion of the Paraíba State, Northeast Brazil, on coordinates 34º50 00 -34º57 30 S and 6º55 00 -7º7 30 W, constitutes a fluvio-marine plain formed by the North Paraíba River and its tributaries Sanhauá, Paroeira, Mandacaru, Tiriri, Tambiá, Ribeira and Guia. This estuary comprises an area of about 260 km2. Increasing human demands on the estuary area and inadequate environment managing have generated conflicts. The present work main purpose is to evaluate the geodynamic evolution of the North Paraíba River Estuary in the period from 1969 to 2001, using digital image processing techniques, thematic digital cartography and multitemporal data integration, combined to geological-geophysical field surveys. The SUDENE cartographic database, converted to digital format were, used to obtain occupation and topographic maps from 1969 and to generate a Digital Elevation Model (DEM). Digital Landsat 7 ETM+ and Spot HRVIR-PAN satellite images interpretation allowed the environmental characterization of the estuary. The most important digital processing results were achieved color composites RGB 5-4-3, 5-3-1, 5-2-NDWI and band ratio 7/4-5/3-4/2, 5/7-3/1-5/4). In addition the fusion image technique RGBI was used by the inclusion of the Spot HRVRI and Landsat 7 ETM+ panchromatic band on I layer with RGB triplets 5-4-3, 5-3-1 and 5/7-3/1-5/4. The DEM and digital images integration allowed the identification of seven geomorphological units: coastal tableland, flowing tray, tide plain, fluvial terrace, submerged dune, beach plain and beach). Both Side Scan Sonar and Echosound were used to analyse underwater surface and bedforms of the estuarine channel, sand predominance (fine to very fine) and 2D dune features 5 m wide and 0.5 m height. This investigation characterized the estuary as an environment dominated by regimen of average flow. The channel depth varies between 1 m and 11 m, being this last quota reached in the area of Porto de Cabedelo. The chanel estuary is relatively shallow, with erosion evidences mainly on its superior portion, attested by sand banks exposed during the low tide. Multitemporal digital maps from 1969 and 2001 integration were obtained through geoprocessing techniques, resulting the geodynamic evolution of the estuary based on landuse, DEM geomorphology and bathymetric maps

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The area between Galinhos and São Bento do Norte beaches, located in the northern coast of the Rio Grande do Norte State is submitted to intense and constant processes of littoral and aeolian transport, causing erosion, alterations in the sediments balance and modifications in the shoreline. Beyond these natural factors, the human interference is huge in the surroundings due to the Guamaré Petroliferous Pole nearby, the greater terrestrial oil producing in Brazil. Before all these characteristics had been organized MAMBMARE and MARPETRO projects with the main objective to execute the geo-environmental monitoring of coastal areas on the northern portion of RN. There is a bulky amount of database from the study area such as geologic and geophysical multitemporal data, hydrodynamic measurements, remote sensing multitemporal images, thematic maps, among others; it is of extreme importance to elaborate a Geographic Database (GD), one of the main components of a Geographic Information System (GIS), to store this amount of information, allowing the access to researchers and users. The first part of this work consisted to elaborate a GD to store the data of the area between Galinhos and São Bento do Norte cities. The main goal was to use the potentiality of the GIS as a tool to support decisions in the environmental monitoring of this region, a valuable target for oil exploration, salt companies and shrimp farms. The collected data was stored as a virtual library to assist men decisions from the results presented as digital thematic maps, tables and reports, useful as source of data in the preventive planning and as guidelines to the future research themes both on regional and local context. The second stage of this work consisted on elaborate the Oil-Spill Environmental Sensitivity Maps. These maps based on the Environmental Sensitivity Index Maps to Oil Spill developed by the Ministry of Environment are cartographic products that supply full information to the decision making, contingency planning and assessment in case of an oil spilling incident in any area. They represent the sensitivity of the areas related to oil spilling, through basic data such as geology, geomorphology, oceanographic, social-economic and biology. Some parameters, as hydrodynamic data, sampling data, coastal type, declivity of the beach face, types of resources in risk (biologic, economic, human or cultural) and the land use of the area are some of the essential information used on the environmental sensitivity maps elaboration. Thus using the available data were possible to develop sensitivity maps of the study area on different dates (June/2000 and December/2000) and to perceive that there was a difference on the sensitivity index generated. The area on December presented more sensible to the oil than the June one because hydrodynamic data (wave and tide energy) allowed a faster natural cleaning on June. The use of the GIS on sensitivity maps showed to be a powerful tool, since it was possible to manipulate geographic data with correctness and to elaborate more accurate maps with a higher level of detail to the study area. This presented an medium index (3 to 4) to the long shore and a high index (10) to the mangrove areas highly vulnerable to oil spill

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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

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This work presents a study on the environmental vulnerability of the coastal region of Pititinga, Rio do Fogo/RN. The coastal erosion of Pititinga beach was analyzed and considerated as one more process that produces environmental vulnerability in the area of study, taking into account its human and natural environment and establishing the relation between them, to understand the arrangement that produced its spatial configuration. The natural environment was expressed by thematics maps with geology, geomorphology, vegetation and soil themes, while the human environment was expressed by the use and occupation of the soil map. The coastal erosion was put in an erosion vulnerability map. The methodological procedure to generate the thematics maps, vulnerability maps and of the erosion coastal involved the bibliographic research, field visits with check-list form fill, collect and analysis of sediment sample, photo-interpretation techniques, integration of the information in a database, data store and spatial analysis in a Geographic Information System (GIS) ambient. The natural vulnerability map shows a predominancy of environments with low (29,6%) or medium (42,4%) vulnerability, pointed the frontal and mobile dune as the areas with the highest vulnerability. The environmental vulnerability map, presents a predominancy of environments with low vulnerability (53,8%), with the high vulnerability concentrated on Pititinga community. The coastal erosion vulnerability presented distinct behaviors on three sections among the coastal line according each one characteristics. Where there are frontal and transgressive dunes, vulnerability are, generally, medium or low, respectively, and in the absence of them, as what occurs in Pititinga community, the vulnerability is predominately very high

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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

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In the shallow continental shelf in Northeastern Rio Grande do Norte - Brazil, important underwater geomorphological features can be found 6km from the coastline. They are coral reefs, locally known as “parrachos”. The present study aims to characterize and analyze the geomorphological feature as well as the ones of the benthic surface, and the distribution of biogenic sediments found in parrachos at Rio do Fogo and associated shallow platforms, by using remote sensing products and in situ data collections. This was made possible due to sedimentological, bathymetric and geomorphological maps elaborated from composite bands of images from the satellite sensors ETM+/Landsat-7, OLI/Landsat-8, MS/GeoEye and PAN/WordView-1, and analysis of bottom sediments samples. These maps were analyzed, integrally interpreted and validated in fieldwork, thus permitting the generation of a new geomorphological zoning of the shallow shelf in study and a geoenvironmental map of the Parrachos in Rio do Fogo. The images used were subject to Digital Image Processing techniques. All obtained data and information were stored in a Geographic Information System (GIS) and can become available to the scientific community. This shallow platform has a carbonate bottom composed mostly by algae. Collected and analyzed sediment samples can be classified as biogenic carbonatic sands, as they are composed 75% by calcareous algae, according to the found samples. The most abundant classes are green algae, red algae, nonbiogenic sediments (mineral grains), ancient algae and molluscs. At the parrachos the following was mapped: Barreta Channel, intertidal reefs, submerged reefs, the spur and grooves, the pools, the sandy bank, the bank of algae, sea grass, submerged roads and Rio do Fogo Channel. This work presents new information about geomorphology and evolution in the study area, and will be guiding future decision making in the handling and environmental management of the region

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The Cacimbinha and Madeiro beaches are located in the eastern coast of Rio Grande do Norte state, in the municipality of Tibau do Sul. Given the indicative of erosion in the coast of this district and the coastal processes acting on the beaches, the global aim of this project is comprehend the evolution of depositional environment on the Cacimbinha beach, moreover, the project seeks to characterize deposits from the Cacimbinha and Madeiro beaches, according to the geomorphologic compartments identified on these beaches; distinguish the coastal features which possibly interact with the Cacimbinha beach; identify the potential relationship between the sediments from the coastal features and the deposits from Cacimbinha beach; understand which depositional processes that prevail at each facies deposited on the beach; and identify the probable sedimentary environments and its energy of deposition through of the materials recorded on the Cacimbinha beach. This study was based on previous bibliographic and field research, both guided by academic works, laws, concepts and theories concerning the physical geography, geomorphology of the quaternary, sedimentary geology and stratigraphy. Thus, the methodology was divided in three steps: Prefield step: office work was performed; Field step: Sampling of facies of sedimentation; PosField step: analysis and integration of data obtained during the research period. Thus, the results showed deposicional facies with distinguished energy in the relief compartments, beach and terrace. After the sedimentary analysis and its interpretation linked to the architecture of the mounted sections based on drilling, it became possible to trace the evolutionary history of this stretch of beach. Therefore, it can be stated that studies performed on coastal areas are of great importance, as long as, around the world, the most part of urban zones are seated on deposits of quaternary age and, then this work improve the knowledge regarding the sedimentary dynamics of this beach, becoming scientific support for management and planning of this area which focus on, mainly, the foreign tourism