Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2017-04-03T21:15:21Z No. of bitstreams: 1 RenanDaCostaOliveira_DISSERT.pdf: 7111395 bytes, checksum: 623f2ac2cda2fc27ac0ceda280b46337 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2017-04-07T22:14:15Z (GMT) No. of bitstreams: 1 RenanDaCostaOliveira_DISSERT.pdf: 7111395 bytes, checksum: 623f2ac2cda2fc27ac0ceda280b46337 (MD5) / Made available in DSpace on 2017-04-07T22:14:15Z (GMT). No. of bitstreams: 1 RenanDaCostaOliveira_DISSERT.pdf: 7111395 bytes, checksum: 623f2ac2cda2fc27ac0ceda280b46337 (MD5) Previous issue date: 2016-08-29 / A ?rea de estudo localiza-se na regi?o do munic?pio de Bara?na-RN, extremo oeste do Estado do Rio Grande do Norte. Abrange uma superf?cie de 675 Km?, incluindo o Munic?pio de Bara?na, e parte dos munic?pios de Quixer?-CE e Mossor?-RN. O aqu?fero Janda?ra constitui a unidade hidrogeol?gica objeto deste trabalho. Trata-se de um aqu?fero de rochas carbon?ticas utilizado no suprimento h?drico da popula??o urbana (Bara?na) e rural, principalmente da fruticultura irrigada. O objetivo do trabalho ? avaliar o comportamento hidrogeol?gico do aq??fero c?rstico Janda?ra, verificar suas condi??es de utiliza??o, avaliar o car?ter de fluxo subterr?neo, propor o modelo conceitual, al?m de responder a questionamentos sobre o rebaixamento dos n?veis de ?gua. Para isso, foi realizado o levantamento dos dados existentes para a ?rea, a elabora??o de mapas e interpreta??o de imagens, a elabora??o de perfis de po?os, o levantamento de par?metros hidrodin?micos, a avalia??o do fluxo subterr?neo, a avalia??o de recarga e gera??o do modelo conceitual esquem?tico. Com base em dados existentes, a ?rea foi subdividida em tr?s zoneamentos quanto a carstifica??o e identificados por m?todos geof?sicos e esquematizado no modelo conceitual com o auxilio de mapas de estruturas, perfis de po?os e identifica??o de carstes na regi?o. A ?rea possui forte explota??o das ?guas do aqu?fero Janda?ra com utiliza??o principalmente na fruticultura irrigada como mostrou o estudo de utiliza??o das ?guas na regi?o. Tamb?m foram elaboradas as estimativas de reservas com base na varia??o de n?vel da ?gua em po?os selecionados. Os estudos referentes ao fluxo subterr?neo mostraram uma tend?ncia natural de fluxo na dire??o SW-NE, por?m a forte influ?ncia da explota??o das ?guas provocou uma converg?ncia para o setor central da ?rea. A constru??o do modelo conceitual esquem?tico visou identificar as diferentes estruturas apresentadas pelo aqu?fero na regi?o, mostrando a varia??o no desenvolvimento c?rstico. O c?lculo de recarga mostrou o alto potencial do aqu?fero Janda?ra, com rendimento m?dio de 45%, a an?lise dos registros de chuvas e n?veis est?ticos mostrou que a causa para o rebaixamento das ?guas subterr?neas possui dois fatores importantes: a forte explota??o das ?guas aliada as secas prolongadas. / The study area is located in the region of Bara?na-RN city, extreme West of the State of Rio Grande do Norte. It covers an area of 675 square kilometers, including the Municipality of Bara?na, and part of the municipalities of Quixer?-CE and Mossoro-RN. The Janda?ra aquifer constitutes the hydrogeological unit and it is the object of this work. It is an aquifer of carbonate rocks used in the water supply of urban and rural population, mainly of the irrigated fruit-growing. The objective of this work is to evaluate the hydrogeological behavior of the Janda?ra karst aquifer, to verify its conditions of use, to evaluate the underground flow character, to propose the conceptual model, and to answer questions about the lowering of water levels. For this, was performed the survey of the existing data for the area, the elaboration of maps and interpretation of images, the elaboration of well profiles, the hydrodynamic parameters survey, the underground flow evaluation, the recharge evaluation and generation of the model conceptual schematic. Based on existing data, the area was subdivided into three zoning for karstfication and identified by geophysical methods and schematized in the conceptual model with the aid of structure maps, well profiles and identification of karst in the region. The area has strong exploitation of the water of the Janda?ra aquifer with use mainly in irrigated fruit-growing as shown by the study of water use in the region. Also were prepared the reserves estimates based on the water level variation in selected wells. The related studies to underground flow showed a natural flow tendency in the SW-NE direction, but the strong influence of the water exploitation caused a convergence for the central sector of the area. The construction of the conceptual schematic model aimed to identify the different structures presented by the aquifer in the region, showing the variation in karstic development. The recharge calculation showed the high potential of the Janda?ra aquifer, with an average yield of 45%, the analysis of rainfall records and static levels showed that the cause for groundwater retraction has two important factors: The strong exploitation of the waters combined with the prolonged droughts.

Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2017-04-03T21:15:21Z No. of bitstreams: 1 OrildoDeLimaESilva_DISSERT.pdf: 10653683 bytes, checksum: a0aad2b3ae9ff3382f46da744b549427 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2017-04-07T22:08:14Z (GMT) No. of bitstreams: 1 OrildoDeLimaESilva_DISSERT.pdf: 10653683 bytes, checksum: a0aad2b3ae9ff3382f46da744b549427 (MD5) / Made available in DSpace on 2017-04-07T22:08:14Z (GMT). No. of bitstreams: 1 OrildoDeLimaESilva_DISSERT.pdf: 10653683 bytes, checksum: a0aad2b3ae9ff3382f46da744b549427 (MD5) Previous issue date: 2016-08-23 / Este estudo teve seu foco em dados de superf?cie e sub-superf?cie rasa, permitindo a caracteriza??o da evolu??o recente do carste epig?nico em quatro est?gios. Durante o Est?gio 1 as fraturas foram abertas pelo processo de dissolu??o, as quais formaram caminhos verticais em escala centim?trica ? m?trica. O conjunto mais abrangente de fraturas concentra a dissolu??o. Ao longo de camadas horizontais intersectadas pelas fraturas tamb?m se observa dissolu??o intraestratal e interestratal. Este sistema de canaliza??o forneceu os caminhos para o fluxo de ?gua, gerando avan?ada lixivia??o. A expans?o alargamento desses condutos em sub-superf?cie ocasiona no Est?gio 2 a queda de blocos, gera??o de dolinas e cavernas. Durante o Est?gio 3, a propaga??o da dissolu??o horizontal e vertical ao longo de fraturas e camadas causam coalesc?ncia de dolinas e captura de pequenos riachos que evoluem para vales incisos e canyons, como pode ser observado no Riacho do Livramento, afluente do rio Apodi-Mossor?, descrito na ?rea III deste estudo. Processos fluviais dominam a dissolu??o do carste durante o Est?gio 4, onde os sedimentos aluviais que recobrem a superf?cie c?rstica carbon?tica, resultando no preenchimento e posterior soterramento de cavernas e dolinas ao longo do vale. Observou-se assim que a influ?ncia do controle tect?nico e do acamamento sedimentar ocorre em todas as fases de evolu??o do carste, resultando nas diversas estruturas e formas de relevo coexistentes espacialmente e que se sucedem, temporalmente, durante os diversos est?gios descritos. Os dados aqui apresentados corroboram os resultados obtidos em outros estudos utilizando dados de GPR, po?os e levantamentos s?smicos, tanto na Bacia Potiguar como em outras bacias sedimentares que evidenciaram que tais estruturas podem ser preservadas ap?s o soterramento. / This research analyzes different types of karst landforms and their relationships with fracture systems, sedimentary bedding, and fluvial processes. We mapped karst features in Cretaceous carbonates of the Janda?ra Formation in the Potiguar Basin, Brazil. The study area is a semi-arid region, with low annual rainfall (600mm) and high evaporation (2000mm). We used high-resolution digital elevation models acquired by Light Detection and Ranging (LiDAR) and aerial ortophotographs acquired by unmanned aerial vehicle (UAV). This study focuses on surface and near surface process and grouped karst evolution into four stages. Fractures were opened by dissolution, which form vertical fluid pathways during stage 1 in a centimetric to metric scale. The most pervasive set of fracture concentrates the dissolution. Coeval intrastratal and interstratal dissolution occurred along horizontal layers, which bound dissolved fractures. This conduit system acted as pathways for water flow, which caused advanced leaching. The enlargement of conduits in subsurface contributed to the collapse of blocks, generation of sinkholes, and caves expansion in stage 2. During stage 3, propagation of horizontal and vertical dissolution along fractures and layers cause coalescence of sinkholes and capture of small streams. Fluvial processes dominate karst dissolution during stage 4, where alluvial sediments that caps the carbonate karst surface and fill caves and sinkholes along the valley. Tectonic and sedimentary bedding control all stages of karst evolution and resulting structures and landforms formed during these stages coexist. Comparisons with GPR, borehole and seismic surveys in sedimentary basins indicate that these structures are preserved after burial.