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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Contribui??o da catodoluminesc?ncia para o entendimento da diag?nese da forma??o Janda?ra: ?reas do campo de petr?leo da fazenda Bel?m e Lajedo do Ros?rio

Fernandes Neto, Severino 16 December 2009 (has links)
Made available in DSpace on 2014-12-17T14:08:43Z (GMT). No. of bitstreams: 1 SeverinoFN_DISSERT.pdf: 3869767 bytes, checksum: 945ebd462d1133b15f06af55a2ec4392 (MD5) Previous issue date: 2009-12-16 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico / The general objective of this study was to contribute to the understanding of the chemical evolution of fluids that percolate through carbonate rocks of the Janda?ra Formation. The oxidation and reduction conditions in which grains, source and cement were formed was investigated using the cathodoluminescence technique (CL). The study area is located in the west part of the Potiguar Basin (Fazenda Bel?m field) and Ros?rio Ledge (Felipe Guerra municipality, State of Rio Grande do Norte, Brazil). The analysis of thin sections of carbonate rocks under CL revealed that grains (allochemical or not) and diagenetic products (micritization, dolomitization, neomorphism and cementation) exhibit since absence of luminescence the various luminescence colors (yellow, orange, red, brown, and blue) in a variety of intensities. As pure calcite shows dark blue luminescence, the occurrence of different luminescence colors in calcite crystals suggest one or more punctual crystal defects such as free electron, free space and impurity. The dyeing of thin sections with alizarin and potassium ferrocyanide revealed the absence of ferrous carbonate in the different lithotypes of Janda?ra Formation. Therefore, the different colors and intensities of CL observed in these rocks are probably caused by the presence of ion activators such as Mn2+ and is not an activator/inhibitor combination. In the same way, the absence of luminescence is very probably caused by the absence of activator ions and not due to the low concentration of inhibitor ions such as Fe2+. The incorporation of Mn2+ in the different members of the Janda?ra Formation must have been controlled by the redox state of the depositional environment and diagenesis. Therefore, it is possible that the luminescent members have been formed (e.g.,ooids) or have been modified (gastropod neomorphism) under reduction conditions in the depositional environments, in subsurface during the burial, or, in the case of Rosario Ledge samples , during the post-burial return to surface conditions. As regards the sudden changes from low to moderate and to strong luminescence, these features should indicate the precipitation of a fluid with chemical fluctuations, which formed the frequent zonations in the block cement of the Rosario Ledge samples. This study suggests that the different intensities and colors of CL should be correlated with the Mn2+ and Fe2+ contents, and stable isotopes of samples to determine the salinity, temperature, pH e Eh conditions during deposition / O objetivo geral deste trabalho foi contribuir para a compreens?o da evolu??o qu?mica dos fluidos percolantes atrav?s das rochas carbon?ticas da Forma??o Janda?ra. As condi??es oxidantes e redutoras nas quais gr?os, matriz e cimento foram formadas foi investigada usando a t?cnica da catodoluminesc?ncia (CL). A ?rea de estudo localiza-se a oeste da Bacia Potiguar (Campo da Fazenda Bel?m) e no Lajedo do Ros?rio (Munic?pio de Felipe Guerra, Estado do Rio Grande do Norte, Brasil). As an?lises das l?minas delgadas das rochas carbon?ticas sob CL revelou que gr?os (aloqu?micos ou n?o) e produtos diagen?ticos (micritiza??o, dolomitiza??o, neomorfismo e cimenta??o) exibiu desde aus?ncia de luminesc?ncia ? v?rias cores de luminesc?ncia (amarela, laranja, vermelha, marrom e azul) numa variedade de intensidades . Como a calcita pura mostrou luminesc?ncia azul escuro, a ocorr?ncia de diferentes cores de luminesc?ncia em cristais de calcita sugere um ou mais defeitos pontuais nos cristais tais como el?trons livres, espa?os livres e impurezas. O tingimento das l?minas delgadas com alizarina e ferrocianeto de pot?ssio revelou aus?ncia de carbonatos ferrosos nos diferentes lit?tipos da Forma??o Janda?ra. Portanto, as diferentes cores e intensidades de CL observada nestas rochas s?o provavelmente causadas pela presen?a de ?ons ativadores tais como Mn2+ e n?o uma combina??o ativador / inibidor. Da mesma forma, a aus?ncia de luminesc?ncia ? muito provavelmente causada pela aus?ncia de ?ons ativadores e n?o devido a uma baixa concentra??o de ?ons inibidores tais como Fe2+. A incorpora??o do Mn2+ nos diferentes constituintes da Forma??o Janda?ra deve ter sido controlada atrav?s do estado redox do meio ambiente deposicional e diagen?tico. Portanto ? poss?vel que os constituintes luminescentes tenham se formados (Ex: o?ides) ou tenham sido modificados (Ex: neomorfismo de gastr?podes) sob condi??es redutoras no meio ambiente deposicional, em subsuperf?cie durante o soterramento, ou, no caso das amostras do Lajedo do Ros?rio, durante o p?s-soterramento, no retorno ?s condi??es superficiais. No que diz respeito ?s mudan?as bruscas de luminesc?ncia baixa para moderada e forte, estas caracter?sticas devem indicar a precipita??o de um fluido com flutua??es qu?micas, nas quais formou freq?entes zona??es no cimento blocoso das amostras do Lajedo do Ros?rio. Este estudo sugere que as diferentes intensidades e cores de CL deve ser correlacionado com o conte?dos de Mn2+ e Fe2+ e is?topos est?veis das amostras para determinar a salinidade, temperatura, pH e Eh durante deposi??o
2

Československé hudební elity na přelomu osmdesátých a devadesátých let 20. století / Czechoslovak musical elite in the late eighties and early nineties of the 20th century

Matějíček, František January 2012 (has links)
At the turn of the eighties' and nineties' of the 20th century, correspondingly to the whole social scale, significant changes happened on the domestic music scene. The musical and the creative elite were confronted with the Anglo-American production, and were forced, in a number of cases, to come up with the alternative ways of expressing themselves under the new circumstances. The goal of this thesis is to compare and contrast the situation on the domestic scene during the period right before the November 1989 and the period to follow; based on the various testimonies of popular Czechoslovakian musicians. The research aims to collect the information regarding contemporary popularity of the Czechoslovakian modern music and authors from the eighties'. I'm trying to verify if the critique perspective of one part of the public experts on the allegiance of the musical elite and the ideology of the pre-November regime is justified or not. At the same time, the thesis follows the fortune of the music stars in relation to the changing social order and, in addition to it, establish the basis for the study of the further research in the field.
3

How individuals engaged in social work in Bali perceive their room for action when working with jandas : A qualitative study on social work with socially vulnerable women in Bali / Hur individer som är engagerade inom socialt arbete på Bali upplever sitt handlingsutrymme i sitt arbete med jandas : En kvalitativ studie om socialt arbete med socialt utsatta kvinnor på Bali

Johansson, Camilla, Rosenblad, Elin January 2023 (has links)
The main purpose of this study is to investigate how individuals engaged in social work with socially vulnerable women in Bali perceive their room for action. Our participants' clients are widows, divorced women, unmarried women, or women with children born out of wedlock. In our thesis, we refer to these women as jandas. In an environment influenced by cultural and patriarchal norms, we explore in this essay how they perceive their professional roles in terms of roomfor action, challenges, motivational drivers, and approaches to promoting empowerment. Our aim is to enrich the understanding of the diverse spectrum within which our participants operate. This inquiry aims to uncover the motivating factors influencing our interview subjects, to discern the hurdles they encounter concerning agency in the context of Bali, and to illuminate their strategies for facilitating empowerment. Employing a qualitative methodology, the research has been conducted through semi-structured interviews involving six seasoned respondents with extensive experience in the field of social work in Bali. Drawing upon prior scholarship concerning Bali's cultural and historical milieu, coupled with theoretical frameworks of socio-legal paradigms and empowerment, we have meticulously analyzed the collected data. The findings from the study reveal that religious and spiritual awakenings significantly underpin the dedication of our participants. Furthermore, it emerges that informal norms rooted in religious customs and patriarchal traditions often wield more influence than formal legal statutes, thereby intricately complicating the landscape of social work. Additionally, the study underscores the prominence of varied approaches to empowerment, which our respondents identify as the most effective means of providing support in the Bali context.
4

Cria??o de zonas de alta permeabilidade em fraturas: modelagem num?rica do Lajedo de Soledade, Forma??o Janda?ra, Bacia Potiguar

Rabelo, Juliana Gomes 06 October 2014 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2016-07-08T21:26:33Z No. of bitstreams: 1 JulianaGomesRabelo_DISSERT.pdf: 6918558 bytes, checksum: 49052116e94f4eb616610a9e4ad69145 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2016-07-12T21:45:11Z (GMT) No. of bitstreams: 1 JulianaGomesRabelo_DISSERT.pdf: 6918558 bytes, checksum: 49052116e94f4eb616610a9e4ad69145 (MD5) / Made available in DSpace on 2016-07-12T21:45:11Z (GMT). No. of bitstreams: 1 JulianaGomesRabelo_DISSERT.pdf: 6918558 bytes, checksum: 49052116e94f4eb616610a9e4ad69145 (MD5) Previous issue date: 2014-10-06 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / O fraturamento em rochas carbon?ticas vem atra?ndo aten??o devido as novas descobertas de petr?leo em reservat?rios carbon?ticos. Este estudo investiga como fraturas (falhas e juntas) submetidas a diferentes campos de tens?es se comportam e como seu comportamento pode estar associado ? gera??o de carste e, consequentemente, ao aumento da porosidade secund?ria em carbonatos. Neste estudo usei imagens de sat?lite e imagens de ve?culos a?reos n?o tripulado, al?m de dados de campo para identificar e mapear falhas e juntas no lajedo de rochas carbon?ticas, que considero ser um bom an?logo para reservat?rio carbonat?co. O lajedo est? localizado na Forma??o Janda?ra, Bacia Potiguar. Os dados de campo foram modelados utilizando o software TECTOS, que usa an?lise de elementos finitos para fraturas 2D. Formam identificados tr?s sets de juntas NS, EW e NW-SE, que foram reativadas como falhas. Os maiores valores de Ratio of Failure by Stress (RFS) obtido na modelagem representam o qu?o perto a rocha est? de tocar a envolt?ria Mohr-Coulomb, que indica a concentra??o da tens?o. Os resultados indicam que as tens?es tect?nicas est?o concentradas em zonas estruturais preferenciais, que s?o locais ideais para a gera??o de dissolu??o nos carbonatos. Observei dissolu??o ao longo de fraturas e planos de estratifica??o em todo o lajedo. No entanto, concluo que os maiores valores de RFS ocorrem no cruzamento e termina??es das fraturas. Estes s?o lugares de concentra??o do carste. Finalmente sugiro que existe uma rela??o direta entre a concentra??o da tens?o e a localiza??o da dissolu??o em rochas carbon?ticas. ABSTRACT The fracturing in carbonate rocks has been attracting increasing attention. This study investigates how the fractures (faults and joints) behaves subjected to the stress field and how their behavior may be associated with the generation of karst and consequently to increased secondary porosity in these rocks. We use satellite imagery and VANT image and field data to identify and map the faults and joints, analogous outcrop carbonate rock reservoir in the Janda?ra Formation, Potiguar Basin. Then, we modeled our data using the TECTOS software, which uses finite element analysis for 2D fractures. The results indicate that the tectonic stresses are concentrated in preferred structural zones, which are ideal places for the generation of dissolution in carbonates. The highest values of Ratio of Failure by Stress (RFS) obtained in modeling represents how close the rock is touching the envelopment Morh-Coulomb. We conclude that the highest values of RFS occur at the intersection of fractures and termination thereof. These sites are places of concentration of karst. From the data collected in the field there were three sets of fractures with NS, EW and NW-SE directions. In all cases, the regular pattern of fractures indicates that the system of lineaments 80 ? and 340 ? direction are sets of joints that were reactivated as faults. The joints and faults are shown consistent with the extracted lineaments in the GoogleEarth image. However, it is observed that, in marioria cases, both sets are reactivated as strike-slip faults. Tectonic stylolites occur mainly found in Lajedo showing shortening parallel to the joints (stylolites NS direction), formed in the same tectonic event. In every part of the flagstone we observed dissolution along fractures and bedding planes of the rock. Combining field data with numerical modeling we suggest that there is a direct relationship between stress concentration and location of dissolution. / The fracturing in carbonate rocks has been attracting increasingly attention due to new oil discoveries in carbonate reservoirs. This study investigates how the fractures (faults and joints) behave when subjected to different stress fields and how their behavior may be associated with the generation of karst and consequently to increased secondary porosity in these rocks. In this study I used satellite imagery and unmanned aerial vehicle UAV images and field data to identify and map faults and joints in a carbonate outcrop, which I consider a good analogue of carbonate reservoir. The outcrop comprises rocks of the Janda?ra Formation, Potiguar Basin. Field data were modeled using the TECTOS software, which uses finite element analysis for 2D fracture modeling. I identified three sets of fractures were identified: NS, EW and NW-SE. They correspond to faults that reactivate joint sets. The Ratio of Failure by Stress (RFS) represents stress concentration and how close the rock is to failure and reach the Mohr-Coulomb envelopment. The results indicate that the tectonic stresses are concentrated in preferred structural zones, which are ideal places for carbonate dissolution. Dissolution was observed along sedimentary bedding and fractures throughout the outcrop. However, I observed that the highest values of RFS occur in fracture intersections and terminations. These are site of karst concentration. I finally suggest that there is a relationship between stress concentration and location of karst dissolution in carbonate rocks.
5

Avalia??o do aqu?fero c?rstico Janda?ra na regi?o de Bara?na, Rio Grande do Norte

Oliveira, Renan da Costa 29 August 2016 (has links)
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.
6

Posouzení významu strečinku u hráček florbalu a jeho dopad na zkrácené svaly / Assesmddent the importance of stretching in florball players and its impact on muscle shortening

Kubátová, Adéla January 2021 (has links)
Title: Assessing the importance of stretching among women floorball players and its impact on shortened muscles Objectives: The main goal of the diploma thesis was to determine the functional state of the muscular system and the rate of shortened muscles in a selected group of women in the age range from 18 to 34 years old in the floorball club Banes Florbal Soběslav playing the 1st woman's league. Based on the examination, a set of specific stretching exercises was created and subsequently their effect was verified. The partial goal was to find out the level of stretching before and after the training unit or match using an online questionnaire for players playing in the 1st woman's league. Methods: The diploma thesis was processed as an experimental study. The research involved 16 probands who have been actively involved in floorball for at least 5 years. The research group was equally divided into experimental and contol groups. To obtain the data, a standardized test of shortened muscles according to Janda and palpation examination of trigger points were used. Entrance and exit tests of both groups were performed at intervals of 3 months. During this period the experimental group completed an intervention program. There was no intervention in the control group. An online questionnaire sent via...
7

Posouzení významu strečinku u hráček florbalu a jeho dopad na zkrácené svaly / Assesmddent the importance of stretching in florball players and its impact on muscle shortening

Kubátová, Adéla January 2021 (has links)
Title: Assessing the importance of stretching among women floorball players and its impact on shortened muscles Objectives: The main goal of the diploma thesis was to determine the functional state of the muscular system and the rate of shortened muscles in a selected group of women in the age range from 18 to 34 years old in the floorball club Banes Florbal Soběslav playing the 1st woman's league. Based on the examination, a set of specific stretching exercises was created and subsequently their effect was verified. The partial goal was to find out the level of stretching before and after the training unit or match using an online questionnaire for players playing in the 1st woman's league. Methods: The diploma thesis was processed as an experimental study. The research involved 16 probands who have been actively involved in floorball for at least 5 years. The research group was equally divided into experimental and contol groups. To obtain the data, a standardized test of shortened muscles according to Janda and palpation examination of trigger points were used. Entrance and exit tests of both groups were performed at intervals of 3 months. During this period the experimental group completed an intervention program. There was no intervention in the control group. An online questionnaire sent via...
8

Terapeutická intervence bolesti dolní části zad - porovnání dvou fyzioterapeutických přístupů / Therapeutic intervention of low back pain - comparing of two therapeutic approaches

Pešlová, Veronika January 2014 (has links)
Title: Therapeutic intervention of low back pain - comparing of two therapeutic approaches Objectives: The main objective of this experimental study was to compare two therapeutic approaches: Sensorimotor stimulation by Janda Vávrová and Proprioceptive neuromuscular facilitation in patients with low back pain. Methods: Experimental comparative study aimed at comparing the effect of Proprioceptive neuromuscular facilitation method of Kabat and Sensorimotor stimulation by Jandy and Vávrová in patients with chronic low back pain. The probands were selected from among patients of private healthcare facilities Medi-centre Skalka s.r.o. The assessment of pain, we used a standardized questionnaire Oswestry. The data will be processed using statistical method Mann-Whitney U test. Results: The study showed no significant difference in treatment effect low back pain between Sensorimotor stimulation method by Janda and Vávrová and Proprioceptive neuromuscular facilitation. Keywords: Proprioceptive neuromuscular facilitation, Sensorimotor stimulation by Janda Vávrová, low back pain.
9

Evolu??o dos processos de carstifica??o da forma??o Janda?ra, Bacia Potiguar, utilizando dados obtidos por LiDAR e VANT

Silva, Orildo de Lima e 23 August 2016 (has links)
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.

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