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1
Fleurent, Léonora. "Mécanismes d’enregistrement géochimique liés à des processus cinétiques au moment de la précipitation des travertins." Thesis, Université Paris-Saclay (ComUE), 2015. http://www.theses.fr/2015SACLS204/document.
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Si la relation entre l’enregistrement géochimique au sein de ces travertins et les paramètres environnementaux semble admise, le détail des processus, notamment cinétique et dégazage, ainsi que leur poids respectifs dans les reconstitutions paléoenvironnementales ne sont clairement établis. Afin de mieux contraindre ces processus, un travail minutieux de reconnaissance des mécanismes de précipitation et d’enregistrement de la signature géochimique a été effectué sur les travertins –récents et fossiles- d’une source carbogazeuse située dans le Massif Central (France). Il couple expériences de laboratoire innovantes et travail sérié sur le terrain.Le taux de dégazage du CO2 dans les sources carbogazeuses est l’un des facteurs principaux conduisant aux conditions de précipitation via la modulation du taux de précipitation de la calcite et par conséquent, sa composition en 18O et 13C. Les tests en laboratoire ont été conduits en deux étapes : (1) caractérisation des mécanismes de dégazage seuls, et (2) des expériences combinant dégazage et précipitation pour mieux appréhender les processus cinétiques lors de la précipitation des travertins. En parallèle, un travail de terrain spécifique par pose de plaques de plexiglas le long de différents écoulement de la source, nous a permis de connaitre la résolution de précipitation des travertins et d’obtenir une meilleure estimation des facteurs de fractionnement.Les tests en laboratoire confirment que, lors d’un dégazage important, i.e. conduisant à la précipitation de travertins, la spéciation des espèces du carbone inorganique dissout (CID) et les flux entre ces espèces sont des paramètres primordiaux à considérer. Le facteur de fractionnementεDIC-CO2(g) qui dépend du pH suit alors une distillation de Rayleigh dans un système cinétique. Les évolutions des espèces carbonées en solution ont ainsi pu être modélisées à l’aide d’une équation de diffusion faisant intervenir les paramètres propres à l’expérience.Les résultats de terrain permettent de démontrer que les variations de conditions de précipitation sont principalement dues aux variations de conditions hydrodynamiques et, secondairement, aux variations de température, ce qui a pu être modélisé à l’aide de l’équation définie par Plummer en 1968 et qui a montré la variabilité des conditions de précipitation in-situ. Dans le cas des expériences de précipitation en laboratoire et par comparaison avec les données de terrain, le facteur de fractionnement εCID-calcite va dépendre des concentrations de chaque espèce de CID mais aussi de la partition du carbone entre phase gaz et phase solide. Pour l’oxygène 18, de 0°C à 10°C, les résultats acquis sur les travertins actuels nous ont permis d’utiliser la droite définie récemment par Coplen (2007) pour lier de façon fiable la température au moment de la précipitation et le facteur de fractionnement. Toutefois, pour des températures plus élevées, le facteur de fractionnement est plus important que ce qu’il devrait et confirmant ainsi la non-représentativité des droites de Coplen pour la détermination de la température de précipitation. Lors des expériences de précipitation la tendance est inverse à celle observée pour les travertins confirmant l’influence de la vitesse de dégazage et de l’indice de saturation sur le fractionnement isotopique. Nous avons également confirmé avec les expérimentations, l’impact de la vitesse de précipitation sur les teneurs isotopiques enregistrées dans les travertins.Ce travail a mis en lumière des mécanismes cinétiques complexes et qui ne sont pas complètement contraints par la seule utilisation des outils isotopiques. L’utilisation du partitionnement des éléments traces est un outil primordial pour appuyer l’étude de ces mécanismesThe response of continental groundwater systems to recent climate fluctuations can be reconstructed via the continuous measurement of groundwater level, spring flow and climatic chronicles. When any data exist, recent reconstructions of groundwater dynamics may be reached through various recorders of environmental and hydrological conditions such as travertine. Although the relationship between geochemical records in travertine and environmental parameters seems to be accepted, the details of processes and their respective weight in the paleo-information are not clearly established.Rate of CO2 degassing in CO2-rich spring likely influences calcite precipitation rate and the related δ18O and δ13C composition. Isotopic equilibrium is rarely maintained during travertine deposition and the degassing rate is the main controlling factor of the disequilibrium. Due to the lack of knowledge, fractionation processes, either kinetic or equilibrium, occurring between CO2-rich water, gas and travertine required specific pH and temperature-controlled laboratory tests. These tests were conducted on synthetic water at different pH to focus only on the degassing processes. Other tests were conducted on trace elements partitioning during calcite precipitation, to identify the origin of isotopic signature variability, and to constraint the way of recording past conditions.All these tests confirmed that during a degassing leading to travertine precipitation, the speciation of dissolved inorganic carbon species is a major parameter to be tackled since a linear relationship between εDIC-CO2(g) and pH is observed. Indeed, we highlighted that for a high degassing rate, the isotopic equilibrium is not reached because the reaction greater involves light isotopes than heavy ones. There is thus different reaction rate between the species of dissolved inorganic carbon, the reactions occurring faster in the water than the one between water and gas, the latter being controlled by diffusion
2
Overby, Steven T., and Daniel G. Neary. "Travertine Geomorphology of Fossil Creek." Arizona-Nevada Academy of Science, 1996. http://hdl.handle.net/10150/296999.
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3
HUILLCA, CARLOS ALBERTO LUZA. "EXPERIMENTAL STUDY OF THE GEOMECHANICAL BEHAVIOR OF TRAVERTINE." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2014. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=24637@1.
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PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIROCOORDENAÇÃO DE APERFEIÇOAMENTO DO PESSOAL DE ENSINO SUPERIOR
PROGRAMA DE EXCELENCIA ACADEMICA
O Travertino é uma rocha amplamente usada no mundo como rocha ornamental, mas suas propriedades petrológicas e mecânicas análogas a rochas carbonáticas de reservatório influenciaram em sua escolha para a compreensão do comportamento geomecânico destas formações. Neste sentido, este trabalho procurou analisar o comportamento geomecânico do Travertino Romano mediante um programa experimental que incluiu uma caracterização da petrologia, da estrutura porosa e do comportamento mecânico da rocha. Foi determinada sua estrutura e textura sedimentar, composição química, mineralógica e índices físicos. Além disso, sua complexa estrutura porosa foi caracterizada por análise de imagens 2D e 3D geradas no microscópio óptico e no micro-tomógrafo de raios-X, com a determinação da presença de macro e micro poros, distribuídos aleatoriamente na rocha com uma baixa conectividade, assim mesmo foi também estabelecida uma relação entre a porosidade e a resistência. Analisaram-se também os resultados dos ensaios de resistência mecânica, que tanto para o estado de tensão uniaxial como triaxial mostraram um decréscimo da resistência com o incremento da porosidade, apresentando um comportamento frágil na maioria dos casos.
The Travertine is a rock widely used in the world as an ornamental rock, but their analogous petrological and mechanical properties to carbonate rocks of reservoir influenced his choice to be able to understand the geomechanical behavior of these formations. Thus, this study sought to analyze the geomechanical behavior of Roman Travertine through an experimental program that included a characterization of petrology, the porous structure and mechanical behavior of the rock. Sedimentary structure and texture, chemical, mineralogical composition and physical indexes was determined. Moreover, Its complex porous structure was characterized by analysis of 2D and 3D images generated in the optical microscope and X-Ray micro CT-scanner, with the determination of the presence of macro and micro pores, randomly distributed in the rock with a low connectivity, so it was also established a relationship between the porosity and strength. Also analyzed the test results of mechanical strength, both to the state of uniaxial to triaxial stress showed a decrease in resistance with increasing porosity, with a brittle behavior in most cases.
4
Kamradt, Ivonne. "Die thüringischen Travertine Verbreitung und Genese am Beispiel ausgewählter Vorkommen." Aachen Shaker, 2009. http://d-nb.info/999440195/04.
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Pechová, Riedlová Mária. "RADNICE - VĚC VEŘEJNÁ, Správní centrum městské části Brno-sever." Master's thesis, Vysoké učení technické v Brně. Fakulta architektury, 2015. http://www.nusl.cz/ntk/nusl-216159.
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The aim of the work was to design a town hall for Brno city, burrough Sever. Currently, the location is separated from public life by a high wall. What is more, it does not match the style of surrounding buildings. The proposed town hall design strives to revive the location. It uses one of the three existing buildings built in 1920. The building is proposed to be rennovated and extended by a new modern architectonic object. This way, the whole complex would naturally fit into the original structure. The location of the town hall merges the historic with the modern introducing new values into the place.
6
Kamradt, Ivonne [Verfasser]. "Die thüringischen Travertine : Verbreitung und Genese am Beispiel ausgewählter Vorkommen / Ivonne Kamradt." Aachen : Shaker, 2009. http://d-nb.info/1161300430/34.
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7
Goffredo, Giovanni Battista. "Smart surfaces for architectural heritage: self-cleaning titanium dioxide nano-coatings on travertine." Doctoral thesis, Università Politecnica delle Marche, 2013. http://hdl.handle.net/11566/242745.
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Lo sviluppo e l'applicazione di trattamenti auto-pulenti su pietre di valore storico e architettonico possono portare a miglioramenti significativi nella conservazione, la protezione e il mantenimento dei Beni Architettonici.
Il biossido di titanio (TiO2) può essere utilizzato per realizzare rivestimenti auto-pulenti trasparenti sulle pietre, limitando interventi di pulizia e manutenzione, l'insorgere di processi di degradazione e riducendo i costi di mantenimento.
La capacità auto-pulente del biossido di titanio è dovuta alle sue due proprietà foto-indotte attivate dall'irraggiamento ultravioletto della luce solare: fotocatalisi e superidrofilia. Lo scopo di questa ricerca è quello di analizzare questo effetto. Due diversi prodotti a base di titania, ottenuti tramite due processi differenti, sono stati depositati sul travertino (una pietra calcarea porosa usata spesso in edifici storici e monumentali) tramite spray, ottenendo un trattamento a strato unico e uno a tre strati per ogni prodotto. Gli effetti del quantitativo depositato di titania sulle caratteristiche delle superfici trattate sono stati considerati nelle analisi seguenti.
Per verificare l'uso del TiO2 nel campo dei Beni Culturali, la conservazione dell'aspetto delle superfici di travertino è stata monitorata analizzando colore e brillantezza.
I possibili effetti dannosi dell'idrofilia foto-indotta e l'eventuale maggiore assorbimento d'acqua da parte della pietra trattata sono stati valutati mediante analisi dell'assorbimento d'acqua per capillarità, dell'angolo di contatto e dell'assorbimento superficiale prima e dopo la deposizione del TiO2.
Test anti-inquinamento e di rimozione dello sporco sono stati effettuati sotto luce UV per stimare l'efficacia auto-pulente.
I risultati sembrano consentire l'uso di trattamenti a base TiO2 su superfici storiche e architettoniche costituite da travertino. Ulteriori analisi sono necessarie per valutare le caratteristiche dei nano-rivestimenti di TiO2.The development and application of self-cleaning treatments on historical and architectural stone surfaces could lead to significant improvements in conservation, protection and maintenance of Architectural Heritage. Titanium dioxide (TiO2) can be used to realize transparent self-cleaning coatings on stone surfaces as an active and preventive protection system, limiting cleaning and maintenance actions, decreasing the onset of degradation processes and reducing maintenance costs. The self-cleaning ability of titanium dioxide is due to its two photo-induced properties activated by ultraviolet irradiation of solar light: photocatalysis and superhydrophilicity. The aim of this research is to analyse this effect. Two different titania-based products, obtained by two different processes, were deposited on travertine (a porous limestone often used in historical and monumental buildings) by spray coating in two different ways, obtaining a single-layer and a three-layers treatment for each product. The effects of deposited amount of titania on the characteristics of treated surfaces were evaluated in following analyses. In order to verify the potential use of titania in the field of Cultural Heritage, the maintenance of appearance properties of the treated travertine surfaces was monitored by colour and gloss analyses. The potential harmful effects of photo-induced hydrophilicity and eventual greater water absorption by treated stone was evaluated through water absorption by capillarity, static contact angle and surface water absorption analyses before and after the TiO2 deposition. De-pollution and soiling removal tests were carried out under UV-light exposure to evaluate photo-induced effects and self-cleaning efficiency. Results seem to allow the use of TiO2-based treatments on historical and architectural surfaces made up by travertine. Further analyses are necessary to evaluate the multidisciplinary features of TiO2 nano-coatings.
8
Frery, Emanuelle. "Circulation épisodique de fluides réactifs le long de failles de l'échelle de travertins à celle de bassins, sur l'exemple du plateau du Colorado (USA)." Phd thesis, Université de Grenoble, 2012. http://tel.archives-ouvertes.fr/tel-00864036.
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Cette thèse s'attache à caractériser l'évolution dans le temps et l'espace des circulations de fluides le long des failles. Une approche multidisciplinaire et multi-échelle a été mise en place sur un exemple naturel dans la région du plateau du Colorado (Utah): du terrain à la modélisation et de la proche-surface au bassin. L'étude des minéralisations en proche surface et leur lien avec le transfert le long des failles a été effectuée sur des travertins récents. L'analyse isotopique et la datation U/Th des veines de travertins révèle des cycles de circulation de fluides enrichis en CO2 et de précipitation épisodiques de carbonates de calcium (travertin) correspondant à des cycles saisonniers ou climatiques (annuels et centennals) ainsi qu'à des cycles qui s'apparentent à des cycles sismiques de l'ordre du millier d'années. Ces données permettent de calibrer le volume de CO2 qui a fuit par la faille. Des zones de paléo-circulation, témoins de l'activité des failles sur le long-terme, sont observées sous forme de blanchiment chimique ("bleaching") des grès à l'affleurement, et ont été étudiées à l'échelle du bassin. Deux épisodes principaux de circulation de fluides le long des failles ont été distingués : une première circulation durant l'enfouissement maximum puis une seconde circulation le long des réservoirs et des failles, qui est reliée à des phénomènes tectoniques régionaux, compemporains de la remontée du Plateau du Colorado. La dernière circulation s'est découpée en plusieurs pulses avec des circulations de fluides de différente nature (tels que des saumures, des fluides riches en hydrocarbures ou en CO2) au cours du temps et le long des failles.
9
Croci, A. "CARBONATE DEPOSITION IN CONTINENTAL SETTINGS: SPATIAL DISTRIBUTION AND PETROGRAPHY OF LATE MESSINIAN TRAVERTINES IN ALBEGNA BASIN (SOUTHERN TUSCANY) AND LATE PLEISTOCENE TRAVERTINES IN AQUE ALBULE BASIN (TIVOLI, CENTRAL ITALY)." Doctoral thesis, Università degli Studi di Milano, 2016. http://hdl.handle.net/2434/362798.
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The hydrocarbon reservoir discoveries in continental Lower Cretaceous carbonates in the South Atlantic Pre-Salt (offshore Brazil and Angola) have renewed the scientific interest in recent and ancient carbonates developed in lacustrine, hydrothermal and fluvial environments. Outcrop analogues provide key information to improve the understanding of the stratigraphic, sedimentological, diagenetic and petrophysical subsurface reservoir properties and lithofacies spatial distribution. To improve the knowledge about continental carbonates lithofacies types, stratigraphic architecture and diagenesis, this project focuses on two case studies: the Messinian mixed terrigenous-travertine succession of the Albegna Basin (Southern Tuscany, Central Italy) and the Pleistocene Acque Albule Lapis Tiburtinus (Tivoli, Central Italy). In the both studied areas, travertines include facies types precipitated from thermal water through abiotic and biologically influenced processes, ranging from clotted peloidal micrite boundstone, to crystalline dendrites and coated reeds.
The 70 m thick Messinian mixed terrigenous-travertine system, accumulated in the extensional continental Neogene Albegna Basin, was investigated in terms of lithofacies types, depositional environment and their spatial distribution, petrographic analysis, carbon and oxygen stable isotope geochemistry, diagenesis and porosity. The succession recorded three phases of evolution of the depositional system. 1) At the base, a 20 m thick northward prograding hydrothermal travertine terraced slope interfingered in the eastern part with an alluvial plain system prograding northward and westward (Phase I). 2) The continuous travertine succession was interrupted by the deposition of several metres thick alluvial fan breccias intercalated with 2-3 m thick travertine lenses (Phase II). 3) During Phase III, the basin evolved into an alluvial plain with ponds rich in coated reed travertines. Travertine stable isotope signatures during phase I and II confirm the geothermal origin of the precipitating water with 13C value averaging 1.46 ‰ V-PDB, while 18O is -7.50 ‰. Phase III travertines, enriched in coated plants, show lighter 13C values (mean 13C -0.36 ‰; 18O -7.22 ‰) indicative of influence of meteoric water with soil-derived CO2. The paragenetic history of the studied succession shows that it was affected by hydrothermal, meteoric and burial diagenesis. The studied succession was firstly affected by a burial phase, afterwards followed by uplift and exhumation to meteoric diagenesis.
The 20 km2 and 50 m thick Pleistocene travertine succession accumulated in the Acque Albule Basin close to Tivoli village was investigated in terms of lithofacies types, its geometry and architecture, through the analyses and the correlation of six drilled borehole cores. The travertine unit consists of a wedge shape geometry thinning southwards and it is subdivided in a proximal, intermediate and distal part from North to South. The succession recorded four principal units separated by four main unconformities that consist of centimetre to few metres thick intraclastic/extraclastic wackestone to floatstone/rudstone, indicative of periods of non deposition and erosion, due to the temporary interruption of the thermal water out of the springs. The southern part of the wedge is intercalated with conglomerate and sandstone representing palaeo-river channels.
This study shows the stratigraphic architecture and sedimentary evolution of these two decametre scale continental sedimentary successions in which hydrothermal activity and travertine precipitation were driven by the extensional and transtensive tectonic regimes, with faults acting as fluid paths for thermal water and creation of accommodation space for terrigenous and travertine deposition. Humid climate might have been instrumental for the aquifer recharge that fed the hydrothermal vents.
This study proposes two different geological models useful for further comparison with other continental basin successions and hydrothermal travertine systems in outcrops and subsurface. It provides useful information for the petrographic, spatial and reservoir characterization of subsurface travertine analogues.
10
Mitchell, Colin Raymond. "Numerical Simulation of Calcium Carbonate Formation." University of Akron / OhioLINK, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=akron1294360826.
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Lopez, Benjamin. "Architecture et distribution des systemes carbonatés se développant autour des sources hydrothermales : cas d’étude du basin de Denizli (Turquie), de la region de Rapolano (Italie) et de Mammoth Hot Springs (Wyoming, USA)." Thesis, Aix-Marseille, 2015. http://www.theses.fr/2015AIXM4326.
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Les carbonates de sources hydrothermales (ou Geothermal Spring Carbonate, GSC) sont des systèmes carbonatés qui se développent autour de sources dont les eaux ont circulé en profondeur et sont remontées le long de failles perméables. Leur développement est contrôlé en tout premier lieu par la nature des eaux souterraines auxquelles ils sont liés. La formation de ces carbonates dépend d’interactions complexes entre les processus hydrologiques, tectoniques et structuraux se produisant avant l’émergence. Par la suite, la sédimentation est régie par de nombreux processus résultant des variations hydrologiques et chimiques de l’eau ainsi que par l’activité biologique. Du fait des interactions complexes entre ces facteurs, la sédimentation est sensible à de faible variations environnementales et il en résulte ainsi un grand nombre d’environnement de dépôts et de lithofacies.Le but de cette étude est d’améliorer les connaissances et les concepts fondamentaux propres au développement des carbonates de sources hydrothermales (GSC). Pour cela, elle s’appuie principalement sur l’examen des faciès que ce soit à petite échelle, comme l’observation des microstructures (microfabrics), ou à grande échelle, comme leur agencement en trois dimensions. De tels examens ont été effectués dans des sites hydrothermaux où ces carbonates se sont développés au cours du Quaternaire (région de Rapolano en Italie, bassin de Denizli en Turquie ou encore le Parc du Yellowstone dans le Wyoming, USA)Geothermal spring carbonate (GSC) corresponds to a complex carbonate system formed around carbonate-rich springs fed by rising groundwaters along permeable fault zones. Their development is mainly controlled by the nature of springwaters emerging above water table. Therefore carbonate deposition is, in this setting, intimately related to complex interactions between hydrological, tectonic and structural processes occurring prior to water emergence. Moreover, carbonate sedimentation from springwater results from sedimentary processes controlled by complex interactions between hydrological, chemical characteristics and biological activity. Such processes are sensitive to slight environmental variations and thus lead to a large spectrum of lithofacies and ecosystems.The aim of this study is to improve knowledge and fundamental concepts regarding development of geothermal spring carbonates. For that purpose, lithofacies investigation, from microfabrics at micro-scale to 3-dimensional configuration at field-scale, is considered as an essential tool. Such investigations had been carried out in sites where Quaternary and actively forming GSCs were abundant (e.g. Rapolano region, Italy, Denizli Basin, Turkey and Yellowstone National Park, Wyoming, USA)
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Richardson, Justin. "Assessing the preservation potential of biogenic features in pre-Neogene tufas and travertines applications to exobiology /." Connect to this title online, 2005. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=bgsu1116873156.
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Main, Joel. "Using Travertine-Cemented Fault Breccias to Understand the Architecture and History of the Gunnison Fault Zone, eastern Basin and Range, Utah." The Ohio State University, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=osu1440176868.
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Sopaci, Evrim. "Geotechnical Characterization And Rock Mass Classification Of The Antalya Karstic Rock Masses." Phd thesis, METU, 2012. http://etd.lib.metu.edu.tr/upload/12615126/index.pdf.
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This thesis identifies the geotechnical parameters of the Antalya karstic foundation rocks
(travertine/tufa), which are highly variable in nature, by means of geological observations,
geotechnical site investigations, and field and laboratory geomechanics tests to examine
karstic (mainly tufa) rock mass behavior. Several geotechnical parameters such as
porosity, seismic wave velocity, uniaxial compressive strength, Young&rsquos modulus, tensile strength, etc. that are thought to have significant influence on rock mass behavior have been tested and statistically analyzed. Principal component analysis and multiple linear and non-linear regression analyses have been carried out in order to reveal correlations between the geotechnical parameters tested. Porosity has been statistically determined to be one of the major parameters governing the strength of the Antalya tufa rock mass. Intact rock failure criteria, among which Bieniawski&rsquo
s criterion has been proven to be more appropriate for each tufa type (phytoherm framestone, phytoherm boundstone, microcrystalline tufa, phytoclast tufa and intraclast tufa) along with the Antalya tufa rock mass have been determined from the experiments. GSI rock mass classification of the Antalya tufa rock mass, whose GSI value was recommended between 20±
5 and 75±
5, has been attempted to be used in engineering design. Furthermore, the depth and dimension of the karstic cavities and fractures have been investigated by the geophysical tests, surface geological survey and subsurface investigations (borings and observation pits).
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Silva, Victor de Albuquerque. "Proposta metodol?gica para o imageamento digital e modelagem virtual 3d de um bloco de rochas travertinas." Universidade Federal do Rio Grande do Norte, 2013. http://repositorio.ufrn.br:8080/jspui/handle/123456789/18836.
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Previous issue date: 2013-05-21In this paper we present the methodological procedures involved in the digital imaging in mesoscale of a block of travertines rock of quaternary age, originating from the city of Acquasanta, located in the Apennines, Italy. This rocky block, called T-Block, was stored in the courtyard of the Laborat?rio Experimental Petr?leo "Kelsen Valente" (LabPetro), of Universidade Estadual de Campinas (UNICAMP), so that from it were performed Scientific studies, mainly for research groups universities and research centers working in brazilian areas of reservoir characterization and 3D digital imaging. The purpose of this work is the development of a Model Solid Digital, from the use of non-invasive techniques of digital 3D imaging of internal and external surfaces of the T-Block. For the imaging of the external surfaces technology has been used LIDAR (Light Detection and Range) and the imaging surface Interior was done using Ground Penetrating Radar (GPR), moreover, profiles were obtained with a Gamma Ray Gamae-spect?metro laptop. The goal of 3D digital imaging involved the identification and parameterization of surface geological and sedimentary facies that could represent heterogeneities depositional mesoscale, based on study of a block rocky with dimensions of approximately 1.60 m x 1.60 m x 2.70 m. The data acquired by means of terrestrial laser scanner made available georeferenced spatial information of the surface of the block (X, Y, Z), and varying the intensity values of the return laser beam and high resolution RGB data (3 mm x 3 mm), total points acquired 28,505,106. This information was used as an aid in the interpretation of radargrams and are ready to be displayed in rooms virtual reality. With the GPR was obtained 15 profiles of 2.3 m and 2 3D grids, each with 24 sections horizontal of 1.3 and 14 m vertical sections of 2.3 m, both the Antenna 900 MHz to about 2600 MHz antenna. Finally, the use of GPR associated with Laser Scanner enabled the identification and 3D mapping of 3 different radarf?cies which were correlated with three sedimentary facies as had been defined at the outset. The 6 profiles showed gamma a low amplitude variation in the values of radioactivity. This is likely due to the fact of the sedimentary layers profiled have the same mineralogical composition, being composed by carbonate sediments, with no clay in siliciclastic pellitic layers or other mineral carrier elements radioactive
Nesse trabalho s?o apresentados os procedimentos metodol?gicos envolvidos no imageamento digital em mesoescala de um bloco de rochas travertinas de idade quatern?ria, oriundas da cidade de Acquasanta, situada na cordilheira dos Apeninos, na It?lia. Esse bloco rochoso, denominado de T-Block, foi armazenado no p?tio do Laborat?rio Experimental de Petr?leo "Kelsen Valente" (LabPetro), da Universidade Estadual de Campinas (UNICAMP) para que a partir dele fossem realizados estudos cient?ficos, principalmente para grupos de pesquisa das universidades e centros de pesquisa brasileiros que atuam nas ?reas de caracteriza??o de reservat?rio e imageamento digital 3D. A proposta deste trabalho consiste na elabora??o de um Modelo de S?lido Digital, a partir da utiliza??o de t?cnicas n?o-invasivas de imageamento digital 3D das superf?cies interna e externa do T-Block. Para o imageamento das superf?cies externas foi utilizada a tecnologia LIDAR (Light Detection and Range) e para o imageamento das superf?cies internas foi feita a utiliza??o do Ground Penetrating Radar (GPR), al?m disso, foram adquiridos perfis de Gamma Ray com um Gamaespect?metro port?til. O objetivo do imageamento digital 3D consistiu na identifica??o e parametriza??o de superf?cies geol?gicas e de f?cies sedimentares que pudessem representar heterogeneidades deposicionais em mesoescala, tomando como base de estudo um bloco rochoso com dimens?es de aproximadamente 1,60m x 1,60m x 2,70 m. Os dados adquiridos por meio do Laser Scanner terrestre disponibilizaram informa??es espaciais georreferenciadas da superf?cie do bloco (X, Y, Z), al?m de valores de varia??o de intensidade de retorno do raio laser e dados RGB com alta resolu??o (3 mm x 3 mm), totalizando 28.505.106 pontos adquiridos. Essas informa??es foram utilizadas como auxilio durante a interpreta??o dos radargramas e est?o prontas para ser exibidas em salas de realidade virtual. Com o GPR, foram adquiridos 15 perfis de 2,3 m e 2 grids 3D, cada um com 24 se??es horizontais de 1,3 m e 14 se??es verticais de 2,3 m, tanto com a antena de 900 MHz quanto com a antena de 2600 MHz. Por fim, o uso do GPR associado ao Laser Scanner possibilitou a identifica??o e mapeamento 3D de 3 radarf?cies distintas as quais foram correlacionadas a 3 f?cies sedimentares j? que j? haviam sido definidas no inicio do trabalho. Os 6 perfis de raios gama mostraram uma baixa varia??o na amplitude dos valores de radioatividade. Provavelmente, isso ocorreu devido ao fato das camadas sedimentares perfiladas possu?rem a mesma composi??o mineral?gica, sendo compostas por sedimentos carbon?ticos, com aus?ncia de argila silicicl?stica nas camadas mais pel?ticas ou de outro mineral portador de elementos radioativos
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Barilaro, F. "THE CHARACTER AND SPATIAL DISTRIBUTION OF HOLOCENE AND PLEISTOCENE HYDROTHERMAL TRAVERTINES IN THE ALBEGNA VALLEY, SOUTHERN TUSCANY (CENTRAL ITALY)." Doctoral thesis, Università degli Studi di Milano, 2013. http://hdl.handle.net/2434/216125.
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Characterization of Pleistocene hydrothermal travertine deposits in the Albegna Valley, Southern Tuscany, Central Italy.
A Pleistocene travertine body, cropping out on the Pianetti Terrace, central-eastward area of the Neogene Albegna Basin (Southern Tuscany, central Italy) was investigated: 1) to define the geometry of the sedimentary body and depositional environments, including their lateral and vertical evolution; 2) to characterize the varieties of hydrothermal travertine carbonate fabrics; 3) to improve the understanding of the abiotic and microbially mediated processes that control calcium carbonate precipitation in hot-spring settings; 4) to establish the link between fabric types and travertine depositional environments. The Pianetti travertine body, well exposed within an active quarry, exhibits a wedge shape differentiated into three decametre scale travertine units. Exposure surfaces represented by claystone layers separate the deposit in three travertine units and constitute the travertine sequence boundaries, suggesting an intermittent accretion of the travertine system. Different architectural patterns including clinoforms, stepped and sub-horizontal layers corresponding to smooth slope, terraced slope and pond depositional environments, respectively, were individuated within the travertine units. The geometry and the relative depositional systems of each unit are controlled by different factors such as the location, typology and activity (water supply, hydrostatic pressure of the spring) of the hydrothermal vents, roughness of pre-existing surface and topography along which hydrothermal water flew and mixing with meteoric water. A large variety of fabric types characterize the Pianetti travertine body. Eight main categories of fabric types and the relative sub-categories can be essentially classified into three classes: 1) travertine boundstone and cementstone s.l. in which the original components are directly precipitated from hydrothermal thermal water; 2) encrusted travertine in which original components (acting as substrate) are directly encrusted by carbonate precipitated by flowing hydrothermal water; 3) carbonate grains packstone/grainstone to floatstone/rudstone formed by fragments of already lithified travertine precipitates (intraclasts) and other lithoclasts.
Pore structure (ranging from depositional to secondary porosity) is an important component of travertine fabrics. Porosity and permeability investigations (Helium techniques, microCT scanning and image analysis software AVIZO) shows that travertines display a wide range in porosity and permeability that is a direct function of: 1) primary fabric orientation; 2) diagenesis; 3) travertine fabric.
The distinguished fabric types reflect the precipitation processes due to an interplay of abiotic and biotic processes (biologically induced by microbial metabolic process or simply influenced by nucleation on microbial biofilm substrate) and subsequent diagenesis. The physical-chemical and biological interaction is also registered in travertine isotopic geochemistry. Organic matter remains and organomineral nano-globules within the Pianetti travertine suggest that for some precipitates the biologic influence is fundamental. However, even for the biologically induced mineralization, abiotic processes and physical-chemical characteristic of the precipitating thermal water are necessary for travertine formation. A relationship between fabric types and velocity/turbulence and discharged volumes of the flowing water is suggested. In addition, fabrics occurring in low energy areas might be more biologically influenced than fabrics occurring in fast flowing dipping surface for which the abiotic processes of physical degassing might prevail. Many fabrics seem to represent transitional forms of a continuum between the two end-members of purely abiotic and microbially mediated (influenced/induced) precipitates.
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Šobich, Vladimír. "Hudba jako veřejný prostor – Nový koncept brněnské Filharmonie." Master's thesis, Vysoké učení technické v Brně. Fakulta architektury, 2015. http://www.nusl.cz/ntk/nusl-216173.
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The building structure of new philharmonic orchestra is a longstanding dream of concert hall, whose level is comparable to state-of -the-art concert halls in the world. Where should be the new building located was one of the demands of my assignment. How to involve contemporary architecture to historical context or to urban context in a way that the location of the building will agree with its place in the society, but in a way that it will still respect the heritage of contemporary philharmonic orchestra and heritage of Teofil Hansen? The main aim of the design was to find out the most appropriate location and to design the building structure of new philharmonic orchestra that would meet all contemporary acoustic and personal requirements and would take into consideration all development trends.
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Curie, Julien. "Les travertins anthropiques, entre histoire, archéologie et environnement : étude geoarchéologique du site antique de Jebel Oust (Tunisie)." Thesis, Dijon, 2013. http://www.theses.fr/2013DIJOL032/document.
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Le travertin, connu sous le terme de lapis tiburtinus dans l’Antiquité romaine, est une roche issue de la précipitation du carbonate dissous dans les eaux de sources chaudes (travertins) ou froides (tufs calcaires), sous l’influence de processus physico-chimiques et/ou biologiques. Ce phénomène est décrit dès l’époque gréco-romaine par les auteurs antiques (Strabon, Pline l’Ancien, Vitruve), qui témoignent d’une roche qui se forme sous leurs yeux, qui dessine le paysage et qui est largement exploitée pour la construction (p. ex. le Colisée à Rome, le Temple grec de Ségeste en Sicile). Abondamment répartis à la surface de la Terre et caractérisés par une certaine diversité morphologique, les travertins représentent d’excellents enregistreurs des conditions climatiques et hydrologiques de leur dépôt, offrant un potentiel très fiable d’archives sédimentaires utilisées au sein de problématiques paléoenvironnementales. La notion de travertins anthropiques définie ici prend en compte l’influence de l’Homme sur ces formations sédimentaires et les eaux qui leur sont associées. Elle est illustrée par une approche géoarchéologique des dépôts de travertins préservés sur le site antique de Jebel Oust, en Tunisie, où l’exploitation d’une source chaude est attestée depuis le début de notre ère jusqu’à son tarissement dès la fin de l’Antiquité tardive. La source thermale surgissant sur le versant oriental de la montagne fut l’objet d’un culte aux époques romaine puis paléochrétienne et alimentait en eau chaude, par le biais d’un aqueduc, un édifice thermal localisé en aval. Notre approche géoarchéologique met en lumière l’anthropisation du versant qui se traduit par un contrôle du fonctionnement de la source chaude et des dynamiques sédimentaires associées. En parallèle, l’analyse des travertins préservés au sein des structures antiques révèle des informations primordiales sur les conditions de déroulement du culte et sur les pratiques balnéaires (fonction des salles thermales, gestion de l’eau, phases de réfection, états d’abandon). Une vision plus générale d’une géoarchéologie des travertins anthropiques propose une nouvelle approche des problématiques liées à l’eau, en insistant sur la gestion plus ou moins complexe d’une source carbonatée, chaude ou froide, et en précisant le degré d’impact humain sur le développement des travertinsTravertine, known as lapis tiburtinus during Roman times, are continental limestones precipitated in calcareous environments from thermal waters of hot springs (travertine) or cool waters of karstic springs (calcareous tufa). This phenomenon is well-known during Classical Antiquity and had been described by several ancient authors (Strabo, Pliny the Elder, Vitruvius) who depicted a stone that forms extremely rapidly, a stone that outlines the landscape and which is largely used for construction (e.g. The Colosseum in Roma, the Greek temple at Segesta in Sicily). These deposits are widespread on Earth’s surface showing various morphologies and are great sedimentary records of climatic and hydrologic conditions. Thus they represent valuable proxies for palaeoenvironmental studies. The notion of anthropogenic travertine takes into consideration human impact on these deposits and on travertine-depositing waters. It is documented by the study of the roman site of Jebel Oust, Tunisia, where the exploitation of a hot spring is attested from the first century A.D. to the end of Late Antiquity. The site is characterized by a temple settled around the spring’s vent associated with Roman baths located downstream and supplied with hot water via an aqueduct. Our geoarchaeological approach brings to light the anthropization of the regional geosystem expressed by an entire control over the hot spring and its associated deposits. Furthermore the study of travertines preserved in the archaeological structures reveals precious and original information about water cult and bathing practices during Antiquity (thermal rooms function, water management, repair phases, states of neglect and decay). Moreover, geoarchaeology of anthropogenic travertine intends to offer a new approach of research‘s problematic dealing with water managements and integrating human impact on travertine’s development
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Hoffmann, Frédéric. "Les tufs et travertins en Périgord-Quercy /." [Pessac] : [Presses universitaires de Bordeaux], 2005. http://catalogue.bnf.fr/ark:/12148/cb40117766d.
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Chalmers, Rhona Mary Lindsay. "Neotectonic fracturing associated with Quaternary Travertines." Thesis, University of Bristol, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.265417.
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Hoffmann, Frédéric. "Les tufs et travertins en Périgord-Quercy : étude de la dynamique passée et du fonctionnement actuel de dépôts carbonatés exokarstiques : géomorphologie, sédimentologie, hydrochimie, anthropisation." Bordeaux 3, 1998. http://www.theses.fr/1998BOR30066.
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Les travertins, depots carbonates karstiques, sont de tres bons enregistreurs et indicateurs des destabilisations du milieu naturel dans trois domaines. Tout d'abord, ces depots correlent les periodes d'ameliorations climatiques. D'importantes masses de travertins se mettent en place notamment au dernier interglaciaire. Les indicateurs paleoenvironnementaux contenus dans ces depots permettent de mieux preciser ces periodes, completes par un important travail de datation. A partir de l'holocene, l'implication de l'homme devient de plus en plus grande dans l'evolution du milieu naturel. Les calcimetries fines precisent la composition des sediments et soulignent le role joue par les bio-organismes incrustants. Cette biocarbonatogenese est a relier avec le milieu physico-chimique qui fourni ces carbonates. L'homme intervient dans les processus de depot depuis 7000 ans. Cette pression anthropique, tres forte aujourd'hui, prend des formes plus insidieuses (polluants). L'homme interrompt actuellement l'incidence du climat sur ces processus, dans une periode favorable a la travertinisation. Il rompt une formidable chaine d'enregistrement d'informations environnementales, a l'interface exokarst-endokarst. Les relations travertinisation-endokarst expliquent la dynamique de depot actuelle et passee, notamment par l'explication du fonctionnement en concentration des eaux. Le ruissellement, l'impact des dilutions expliquent pourquoi certains systemes precipitent des carbonates, sans constater de depot important. Cette influence du karst concerne egalement l'hydrodynamique des eaux de surface. Les travertins sont correlatifs d'un fonctionnement karstique ou l'homme intervient. Ils apparaissent comme des marqueurs d'une sequence "karstoanthropique". L'age recent des depots souligne la jeunesse de ce karst actif, inferieur a 200 000 ans. Le perigord-quercy est un remarquable champ d'etude, d'une tres grande diversite de formes et de fonctionnements karstiquesTravertines are karstic carbonated deposits, and are well recording the evolution of passed climates and natural environnement. First, these deposits are related with the period of improved climate, more precisely, in the last interglacial period. In this period, big deposits of travertines appeared. They contained several kinds of informations concerned passed environnements, which are dating. Since the holocene period, the human interference became more and more important. Fine calcimetry can precise the composition of carbonates sediments and the biological processes. The travertines are influenced by the human interference since 7000 years. Nowdays, this human pressure is very strong and break the natural process of deposition, which resulted of karstic and biological influences. The endokarst and its hydrochemistry can explain the actual dynamic of deposition, in relation with hydrodynamic of spring and river. The dilution of karstic water can explain the absence of big deposits of travertines. In fine, this deposit resulted of the karstic dynamic and the human interference. They appeared like "karsto-anthropic" forms. These deposits are very recent, under 200000 years, in the perigord-quercy area
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Omoto, Kunio, and 久仁夫 小元. "南極から美ら海まで : 14C年代測定をはじめて45年." 名古屋大学年代測定資料研究センター, 2011. http://hdl.handle.net/2237/16509.
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Rodriguez, Pumayauri William Vitaliano, and Quispe Robert Alonso Pareja. "Propuesta de una arquitectura empresarial para una empresa manufacturera de travertino." Bachelor's thesis, Universidad Peruana de Ciencias Aplicadas (UPC), 2018. http://hdl.handle.net/10757/625260.
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El presente trabajo es una propuesta de arquitectura empresarial, para una empresa manufacturera de travertinos, utilizando el marco de trabajo TOGAF. En los tiempos modernos las empresas necesitan estrategias para ser competitivas, estas estrategias deben ser soportadas por los procesos de negocio y la tecnología de información. La arquitectura empresarial es la encargada de alinear los procesos y tecnología de la información a la estrategia, buscando la máxima eficiencia para la organización. El objetivo es analizar el proceso de negocio estratégico “mejora continua & innovación” para identificar los proyectos que agreguen valor a la empresa. El trabajo está dividido en cuatro capítulos. El primer capítulo, contiene la definición de la propuesta donde se describe a la empresa, los objetivos y beneficios del presente trabajo. En el segundo capítulo, se recopilan antecedentes, investigaciones previas y consideraciones teóricas que nos permitirán la interpretación de resultados y formulación de conclusiones. En el tercer capítulo se analiza el proceso de negocio estratégico “Mejora continua & innovación”, donde se muestra la arquitectura actual, arquitectura propuesta, las brechas identificadas y cartera de proyectos. En el último capítulo, se desarrolla el proyecto seleccionado utilizando el marco de trabajo scrum. Se demuestra como la arquitectura empresarial logra alinear los proyectos de tecnología de información a los objetivos estratégicos de la empresa de una manera simple y trazable.The present document is an enterprise architecture proposal for a manufacturing company of travertines, using the TOGAF framework. Today’s businesses need strategies to be competitive. These strategies need to be supported by both business processes and information technology. Enterprise architecture is a means of aligning the processes and information technology with business strategies, always with an eye towards maximizing the efficiency of the organization. The aim is to analyze the strategic business process of “continuous improvement and innovation” to identify the projects that add value to the company. The present proposal is divided into four chapters. The first chapter contains the proposal outline, in which we describe the company and delimit the aims and benefits of the present work. In the second chapter, we collect a series of precedents, previous investigations, and theoretical considerations that will allow us to interpret our results and to draw conclusions. In the third chapter, we analyze the strategic business process of “continuous improvement and innovation”, in which we show the current architecture, the proposed architecture, the identified gaps, and the project portfolio. In the last chapter, we develop the selected project by applying a framework scrum. We demonstrate how enterprise architecture succeeds in aligning information-technology projects with the strategic aims of the company in a simple, traceable way.
Tesis
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El, Bouch Abdellatif. "Les travertins du Sai͏̈s de Fès et du Causse d'Imouzzère (Maroc nord central ) : paléoenvironnements quaternaires et anthropisation." Aix-Marseille 1, 1994. http://www.theses.fr/1996AIX10032.
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Trois sites travertinaux ont ete etudies dans le maroc nord central (imouzzere,el gada ait sbaa et fes). Trois formation travertineuses emboitees ont ete distinguees* la plus ancienne,vraisemblablement du pleistocene inferieur,forme un entablement perche. Cette formation induree a subi des modifications diagenetiques; la formation ii probablement du pleistocene moyen-superieur,bien distincte a fes, ou elle montre trois unites: la formation iii forme la basse formation travertineuse,fossilisant le fond de la vallee. Cette formation consideree avant comme wurmienne s'est averee holocene d'apres une datation 14c de 5660 90bp dans les travertins d'imouzzere. D'un ensemble a l'autre,l'enchainement vertical des facies travertineux presente de grandes analogies avec de bas en haut et d'amont en aval, un pole detritique a la base suivi par un role carbonate biochimique (sables oncolitiques, des travertins lamines stromatolihiques, des limons), il peut se terminer par des colluvions fines. A travers divers etudes sedimentologiques, on constate que cet enchainement se correle bien avec les variations de l'environnement. Dans la formation holocene, l'etude sedimentologique des facies a montre d'importants niveaux detritiques. Ces niveaux sont dus en partie au type alluvial des travertins. Il y a une recurrence entre les depots detritiques et les travertins s. S. L'existence des temoins d'occupations humaines dans cette formation peuvent expliquer en partie le detrisme dans les membres superieurs et la degradation des systemes travertineux.
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Altunel, Erhan. "Active tectonics and the evolution of Quaternary travertines at Pamukkale, western Turkey." Thesis, University of Bristol, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.238871.
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Mezrhab, Abdelhamid. "Croûtes calcaires, travertins et paléoenvironnements quaternaires dans le Bni-Iznassen (Maroc nord-oriental)." Aix-Marseille 1, 1994. http://www.theses.fr/1994AIX10050.
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L'enquete menee sur les travertins des bni iznassen (maroc nordoriental) dans cette these a fait l'objet de descriptions et d'analyses de coupes, choisies pour essayer de comprendre des problemes paleoenvironementaux. Ce travail, conprend 3 parties : la premiere partie a ete reservee au cadre physique du contexte; la deuxieme comporte les descriptions et les analyses de coupes parmi lesuelles deux sont des sequences laterales, et une est verticale. Dans le premier cas, nous avons decrit les edifices travertineux de la vallee septentrionale de bou ghriba. Nous avons date et analyse en detail des facies travertineux de detritiques les plus recents. Le rapport croute-travertin, a ete analyse avec plus d'interet. Sur une autre sequence, levee au sud, nous avons etudie les croute de bled eddir et de la plaine occidentale des bessara. Nous ous somme appuye dans cette etude, essentiellement sur l'analyse micromorphologique des facies. Dans le second cas, nous avons decrit et analyse un systeme de croutes zonaires developpees par phenomene de dissolutionprecipitation dans des formations caillouteuse de l'oued sefrou: la troisieme partie concerne l'interpretation generale des formations carbonatees des bni iznassen et le probleme de l'accumulation actuelle du calcaireThe study carried out on the tufa and calcretes of bni iznassen region (north-east of morroco) in this research aimed to describe and to analyse the section chosen in order to understand the palaeoenvironmental problems it contains 3 parts : the first is reserved for the physical framework; the second contains the description and analysis of three sections. Two of them are lateral sequences. The third is a certica sequence. In the first case, the travertine edifices of the septentrional sequence in the bou ghriba valley were desribed. The travertine facies and the most recent detritic in this section were described and analysed in detail. The relationship between calcrete and tufa was analysed with more interest. In the southern sequence, the carcrete of the bled eddir and the western plain of bessara were studied; here the study was based essentially on the mocromorphological analysis of the facies. On the third section, taken from the oues sefrou, a system of laminar calcrete, due to a dissolution-precipitation phonomenon into stony depositis, was analysed ; the third part concerns a general interpretation of the carbonate formation in the bni iznassen and the problem of the present day carbonate accumulation
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CORREA, RODRIGO DOS SANTOS MAIA. "MODELLING THE STRESS-STRAIN BEHAVIOUR OF FAULT ZONES IN TRAVERTINES USING FINITE ELEMENT METHOD." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2016. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=29625@1.
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PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIROCOORDENAÇÃO DE APERFEIÇOAMENTO DO PESSOAL DE ENSINO SUPERIOR
PROGRAMA DE EXCELENCIA ACADEMICA
A partir da amostragem de blocos de travertino cisalhados contendo materiais representativos de zona de dano e/ou núcleo de falhas geológicas, corpos-de-prova cilíndricos constituídos tanto por rocha intacta como por rocha de falha, foram submetidos a ensaios triaxiais multi-estágios com medição de permeabilidade na direção axial, com confinamentos efetivos variáveis de 2, 5, 11, 19 e 29 MPa. O presente trabalho avalia a adequação do modelo Mohr-Coulomb com endurecimento em representar o comportamento tensão-deformação de materiais de zona de falha em travertino observado nos ensaios de laboratório e determina os parâmetros que melhor representam o comportamento experimental, além de analisar a variação da permeabilidade. Para isso, é utilizado o método de elementos finitos, através do software ABAQUS, para modelar os corpos-de-prova e simular o comportamento tensão-deformação de dois dos ensaios triaxiais realizados. Ao final do estudo são determinados os parâmetros de rocha de falha que melhor ajustam aos dados experimentais. Além disso, são determinados fatores multiplicadores de permeabilidade que representam as variações de permeabilidade esperadas a partir das deformações volumétricas nesses materiais. Esse conhecimento tem importante contribuição na previsibilidade do comportamento hidromecânico de falhas geológicas, cujo equilíbrio é alterado com a explotação de reservatórios de petróleo.
From sheared travertine blocks, containing both damage zone and/or gouge representative materials, cylindrical plugs were obtained containing both intact rock and fault materials, and were submitted to triaxial tests with axial permeability measurements in effective confinement pressures of 2, 5, 11, 19 e 29 MPa. This work assess the suitability of Mohr-Coulomb hardening model to represent stress-strain behaviour of travertine fault zone materials observed in laboratory measurements and determines the parameters that best fit the experimental behavior. Furthermore, a permeability variation analysis is conducted. For this, finite element method is used through ABAQUS software, to model the plugs and to simulate the stress-strain behaviour of three triaxial tests. It is possible after all, to determine rock parameters that adjust to experimental results. Besides that, permeability multipliers are determined to adjust permeability changes due to volumetric deformations in these materials. This knowledge is an important contribution to forecast hidromechanical behavior of geological faults that may have stability altered by hydrocarbon exploitation in petroleum reservoirs.
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Sýkorová, Alexandra. "Architektura šedesátých let na Slovensku." Master's thesis, Vysoké učení technické v Brně. Fakulta architektury, 2017. http://www.nusl.cz/ntk/nusl-316307.
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Povojnová architektúra na Slovensku tvorí veľkú časť stavebného fondu a predstavuje obdobie, kedy sa architektúra u nás vyšvihla na svetovú úroveň, obzvlášť v období uvoľnenia. Centrálne plánovanie a ekonomická prosperita štátu dávala príležitosti realizovať veľké stavebné úlohy. Mestské regulatívy sa otvorili a bolo možné stavať vysoko podlažné, veľkoplošné i technologicky náročnejšie komplexy budov. Podporil sa tak povojnový rozvoj priemyslu aj politický marketing expresívnych monumentov. Architektúra obchodných domov Ivana Matušíka na čele s obchodným domom Prior a hotelom Kyjev na kamennom námestí sa k takejto architektúre radí tiež. V očiach laickej, no často i odbornej verejnosti je poznačená rúškom odporu a nevôle k pochopeniu kvôli dobovému kontextu, v ktorom vznikala. Neschopnosť oceniť ju sa v 90. rokoch podpísal na niektorých stavbách ich veľmi necitlivou rekonštrukciou a nenávratnou stratou ( najviac viditeľné je to na stavbe obchodného domu Slimák v Bratislave). Už k tak pokrivenému obrazu, budovám škodí aj starnutie, neadekvátna údržba, zlá interpretácia využitia ich priestorového konceptu a iné stavebné nánosy, ktoré sa usadzujú v jej blízkosti a vo verejnom priestore. Cieľom práce je prehodnotiť postavenie a funkčnú náplň týchto budov a ich verejného priestoru v centre hlavného mesta, oceniť ich výtvarný aj architektonický prínos, no súčasne sa kriticky pozrieť aj na ich tienisté stránky objektívne. V diplomovej práci sa chcem sústrediť len na obchodný dom so spojovacou budovu a hotelom Kyjev na Kamennom námestí. Rekonštrukcia tejto časti Bratislavy je nevyhnutná a mojim záujmom je rešpektovať hodnotné objekty zo 60. rokov tak, aby sa centrum vyvíjalo postupným vrstvením.
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Mallick, Ronzon. "Entwicklung einer Mikrobeprobung zur Th-U-Datierung und Anwendung an quartären Travertinen aus dem Thüringer Becken." [S.l. : s.n.], 2000. http://deposit.ddb.de/cgi-bin/dokserv?idn=961465956.
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Burnside, Neil Murray. "U-Th dating of travertines on the Colorado Plateau : implications for the leakage of geologically stored CO2." Thesis, University of Glasgow, 2010. http://theses.gla.ac.uk/1988/.
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In order to avoid the damaging climatic consequences of rising atmospheric CO2, and reduce current atmospheric CO2 concentrations to pre-industrial levels, anthropogenic CO2 emissions must be mitigated by capturing CO2 at power plants and storing it for thousands of years. Underground storage within deep geological formations, such as depleted gas and oil fields or deep saline aquifers, is the best understood solution for storage of CO2. In order for this method to gain more public and political acceptance it is important to characterise the potential causes, quantities and rates of CO2 release that could result if leakage were to occur from anthropogenic storage projects. This study examines two sites in the Colorado Plateau where faulted and actively leaking CO2 reservoirs provide natural analogues for failed anthropogenic storage sites. The two sites in question, the Little Grand Wash and northern Salt Wash graben faults are situated at the northern end of the Paradox Basin in Utah and represent classic three way traps due to juxtaposition of the shallow, north plunging Green River anticline against a set of east-west trending normal faults. In addition to active leakage sites in each area there are numerous fossilised travertine deposits. Along the Little Grand Wash fault the ancient mounds are restricted to the fault trace whereas ancient travertine mounds associated with the northern fault of the Salt Wash graben are far more numerous and occur up to ~530 m into the footwall of the fault. This more diffuse pattern of flow is due to the outcropping of unconfined aquifer units at the surface. A total of 45 U-Th dates from the majority of these travertine mounds provides a unique data set. The oldest deposits from the Little Grand Wash and northern Salt Wash graben faults produced ages of 113,912 ± 604 and 413,474 ± 15,127 years respectively. Repeat ages show reasonable reproducibility and analytical errors on results are of the order of 1% of the ages. The coupling of travertine elevation measurements with their radiometric ages gives an incision rate for each site. A rate of 0.342 m/ka for the Little Grand Wash fault relates directly to Green River incision and agrees with previous work on the Colorado Plateau, providing a further data point for characterisation of uplift of the province. For the northern fault of the Salt Wash graben a rate of 0.168 m/ka for the tributaries running through the area gives a robust method with which to estimate ages for un-dated mounds. The results of radiometric dating and incision rate age estimation of travertine mounds shows that leakage can last for timescales of 100,000’s of years, while high resolution U-Th dating of an individual mound demonstrated that leakage from a single point can last for a minimum of ~11,000 years. A range of travertine ages show that leakage to the surface has constantly switched location through time, while the presence of three mounds of distinct age at one location demonstrate that pathways can become repeatedly re-used over periods of ~45,000 years. There is no evidence of temporal periodicity in travertine deposition but there is a distinct spatial pattern of leakage as shown by localised similarities in the initial uranium chemistries of travertine mounds. Initial leakage is proximally located to the axial trace of the Green River anticline and subsequent leakage spreads from this central point along the fault plane in both east and west directions. The switching of fluid flow pathways to the surface can be explained by three main mechanisms: mineralisation, 3-phase interference of CO2 related fluid flow and seismically triggered alteration in dynamic strain acting upon the hydrology of the faults. These mechanisms have differing influences in each area - demonstrating that the behaviour of fluid flow switching in a system confined to damage zone fractures (Little Grand Wash fault) is different to a system leaking through an unconfined aquifer (northern fault of the Salt Wash graben). Coupling of travertine ages with estimates of their volumes provided a total worse case scenario for quantity of CO2 leakage of 6.2 x 10^6 ± 1.7 x 10^6 tonnes for the Little Grand Wash fault and 7.4 x 10^6 ± 2 x 10^6 tonnes for the northern fault of the Salt Wash graben. From these totals time averaged leakage rates of 55 ± 15 and 47 ± 13 tonnes/year were estimated for each fault. The leakage rate for the actively precipitating Crystal Geyser travertine (which is the result of anthropogenic exploration drilling) is estimated to be 3,153 ± 851 tonnes/year. These total and modern rates provide analogues for leakage via caprock failure and catastrophic wellbore failure. Applying them to large scale storage sites such as Weyburn and Gorgon revealed that for caprock failure complete leakage of these reservoirs will take place over timescales of 10^5-10^6 years, while for catastrophic failure of a single well complete leakage of these reservoirs could occur over as little as 10^3 – 10^4 years. This finding has important implications for the successful monitoring of anthropogenic storage sites.
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Anselmo, Miranda Aldo Nicolás. "Génesis de travertinos en Baños Colina y Baños Morales, Cajón del Maipo, Región Metropolitana." Tesis, Universidad de Chile, 2017. http://repositorio.uchile.cl/handle/2250/145985.
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GeólogoLa presente investigación tiene por objetivo establecer un modelo genético para los travertinos que se encuentran en Baños Morales y en el Valle de Colina en el Cajón del Maipo, Chile. Para esto se caracterizó la morfología, petrografía y mineralogía de los depósitos con el fin de determinar las condiciones en las cuales se formaron, cuáles fueron los factores principales que controlaron este proceso y una posible relación con la presencia de sistemas geotermales. Se plantea un modelo de formación para los distintos depósitos. El trabajo consistió en tres campañas de terreno para la descripción morfológica de los cuerpos, obtención de precipitado actual y muestras de roca, a las cuales posteriormente se les realizó cortes transparentes, difracción de rayos X y se observaron en el microscopio electrónico de barrido, para determinar las texturas y mineralogía presentes. Se describieron siete cuerpos de travertinos (1) Morales Poniente y (2) Morales Oriente que corresponden a laderas cubiertas por carbonatos, (3) Cascada Baños Morales, que es un depósito activo bajo las termas del mismo nombre, en el Valle de Colina se estudiaron las (4) Terrazas Baños Colina, atracción turística de la zona debido a sus termas, los fissure ridge (5) El Domo, (6) Domo Menor y finalmente (7) La Grieta, un canal autoconstruido de rumbo N40W formado por travertinos bandeados. La mineralogía de los cuerpos varía entre aragonito y calcita según la morfología. Para los travertinos en capas de los fissure ridge se obtuvo mayoritariamente calcita (>90%), mientras que para las Terrazas Colina y La Grieta el porcentaje de aragonito era mayor con un 64% y 90% respectivamente. En los depósitos consolidados de Baños Morales nuevamente se tiene calcita como polimorfo dominante y solo en el precipitado actual ambos minerales presentan un porcentaje similar y se le atribuye a un control por actividad orgánica. En Baños Colina la formación de los depósitos está controlada por la infiltración de aguas meteóricas a través de fallas que facilitan el transporte de fluidos hacia zonas profundas aumentando su temperatura y que ayuda también en el ascenso rápido, por lo tanto, se propone que estos son travertinos termometeógenos precipitados debido a la exsolución de dióxido de carbono desde los fluidos formadores y evidencian un sistema geotermal tectónico ubicado en la zona de estudio. Los travertinos de Baños Morales también de carácter termometeógeno, que han sido formados por aguas meteóricas que al infiltrar calizas y evaporitas obtienen parte de los componentes necesarios para la formación de carbonatos y luego al aflorar estas aguas subterráneas precipitan, pero que a diferencia de Baños Colina los fluidos no logran mantener altas temperaturas (>40°C) al momento de aflorar. No se encontró evidencia en los travertinos de un control estructural para estos depósitos, sin embargo, no se descarta que estén presentes estos factores también.
Este trabajo ha sido financiado por el Centro de Excelencia en Geotermia de Los Andes (CEGA). Proyecto FONDAP CONICYT 15090013
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Dabkowski, Julie. "Analyse géochimique des tufs calcaires en domaine fluviatile ouest européen : reconstitution de variations des paléotempératures et des paléoprécipitations au cours des interglaciaires des stades 11 et 5." Paris, Muséum national d'histoire naturelle, 2011. http://www.theses.fr/2011MNHN0014.
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Cette thèse propose de reconstituer les variations climatiques interglaciaires pléistocènes en contexte fluviatile ouest européen, en développant des marqueurs géochimiques sur les tufs calcaires. L’étude des isotopes stables et des éléments traces de la calcite de tufs pléistocènes montre que ces formations carbonatées sont le support privilégié de reconstitutions des variations de température et de précipitation au cours des interglaciaires. Les premières courbes obtenues à Caours (Somme, SIM 5e), La Celle (Seine-et-Marne, SIM 11) et Condat (Dordogne, SIM 5) ont été comparées avec les informations fournies par la détermination en lame mince d’algues et bactéries à l’origine de la précipitation du tuf et par la malacofaune, ainsi qu’avec d’autres enregistrements continentaux et marins. La synthèse de ces données et de celles du tuf de Saint-Germain-le-Vasson (Normandie) permet aussi la comparaison des conditions climatiques des stades isotopiques 5 et 11 à celles de l’HolocèneThe thesis aims to reconstruct Pleistocene interglacial climate variations in North-western Europe fluvial area, by development of geochemical proxies on calcareous tufas. Calcite stable isotope and trace element investigations from Pleistocene tufa sequences show that these formations are key-deposits for palaeoenvironmental studies and reconstructions of palaeotemperature and palaeorainfall relative variations during the interglacials. The first curves of climatic variations from Caours (Somme, MIS 5e), La Celle (Seine-et-Marne, MIS 11) and Condat (Dordogne, MIS 5) have been compared to palaeoenvironmental data from the determination in thin section of algae and bacteria precipitating tufa and from malacological assemblages, and to other continental and marine records. Moreover, synthesis of these data and those obtained for the Saint-Germain-le-Vasson tufa allows comparison between climatic conditions prevailing during MIS 5 and 11, and during the first half of the Holocene
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Barbosa, Troncoso Carla Valentina. "Mineralogía y geoquímica de travertinos andinos: Caso de estudio Baños Azules, Cajón del Maipo, Chile." Tesis, Universidad de Chile, 2018. http://repositorio.uchile.cl/handle/2250/170031.
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Memoria para optar al título de GeólogaEn este Trabajo de Título se presenta una caracterización morfológica, textural, mineralógica y geoquímica de los depósitos de travertino de Baños Azules, La Cueva y Río Agua Blanca, formados desde las vertientes termales de Baños Azules (BA) y otras surgencias cercanas. El objetivo es comprender los procesos que llevan a la formación de estos depósitos mediante la hidrogeoquímica de los fluidos parentales y el estudio de sus morfologías, texturas, mineralogía y geoquímica. Para esto se realizó una campaña de terreno de tres días en la que se describieron morfológicamente los depósitos y se tomaron muestras de travertino y agua. Las muestras de roca fueron descritas texturalmente con microscopía óptica y microscopía electrónica de barrido (SEM) y luego sometidas a difracción de rayos X (DRX) con el objetivo de determinar su mineralogía. Mediante análisis de espectrometría de masa de razones isotópicas (IRMS) realizados en el Instituto Andaluz de Ciencias de la Tierra, se obtuvieron las composiciones isotópicas de carbono y oxígeno. Las muestras de agua fueron sometidas a análisis composicionales de cationes, aniones y elementos traza en el laboratorio de geoquímica del Centro de Excelencia en Geotermia de los Andes y a análisis isotópicos de deuterio, oxígeno y carbono. BA se encuentra en la ladera norte del Cerro del Museo, en la confluencia de los esteros del Museo y del Azufre y está compuesto por grandes depósitos de ladera, morfología de terrazas y travertino fósil en capas. Unos 300 metros al poniente se ubica La Cueva, una cavidad de 5 m de profundidad con microterrazas y espeleotemas. El tercer depósito se dispone a lo largo del último kilómetro del Río Agua Blanca como una corteza fluvial. La mineralogía de todos estos depósitos está compuesta por calcita y cantidades menores de cuarzo y aragonito. Se encontró también yeso en dos puntos de precipitación activa de carbonato de calcio. Microscópicamente predominan la calcita dendrítica, granos cubiertos por esparita prismática columnar y parches de calcita microesparítica. Imágenes SEM evidencian la actividad de algas y bacterias en depósitos activos. Los fluidos parentales son aguas termales sulfatadas cálcicas de origen meteórico, a excepción de los aportes del Río que podrían estar influenciados por una fuente magmática. Isótopos de carbono en travertinos permiten clasificarlos como termógenos donde el aporte de CO2 provendría de fluidos magmáticos y/o de reacciones metamórficas de decarbonatación. Esta caracterización conduce a plantear que los travertinos del Sector Baños Azules se forman por la infiltración de aguas meteóricas a través de fallas y fracturas a niveles profundos, donde reciben aportes adicionales de CO2 y luego disuelven secuencias calcáreas y de yeso para enriquecerse en calcio y especies carbonatadas. Estos fluidos ascienden a la superficie a través de estructuras, proceso en el cual se produce la pérdida de CO2 a la atmósfera y una consecuente precipitación de carbonato de calcio.
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Aguilar, García Dayana Sihara. "Optimización de los procesos de transformación productiva del mármol travertino mediante la filosofía Kaisen en el Instituto Regional del Mármol." Bachelor's thesis, Universidad Continental, 2019. http://repositorio.continental.edu.pe/handle/continental/5807.
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La presente investigación tiene como objetivo determinar cómo es la optimización de los procesos de transformación productiva del mármol travertino mediante la filosofía Kaizen en el Instituto Regional del Mármol en el periodo 2017-2018 ubicado en el distrito de Sicaya, provincia de Huancayo. El tipo de investigación es aplicada, el nivel de investigación es explicativo y el diseño pre experimental con el uso del pre-test y post-test a un solo grupo. La población considera todos los procesos del Instituto del mármol y la muestra son los procesos de transformación productiva del mármol del Instituto Regional del Mármol para la obtención de baldosas de 40x40 cm.
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Jeandel, Elodie. "Monitoring géochimique par couplage entre les gaz rares et les isotopes du carbon : étude d'un réservoir naturel." Paris 11, 2008. http://www.theses.fr/2008PA112318.
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Dans un objectif de limitation des émissions de gaz à effet de serre dans l'atmosphère, la séquestration géologique du CO2 apparait comme une solution incontournable pour lutter contre le changement climatique. Le développement d’outils de surveillance fiables pour s’assurer de la pérennité et de la sécurité des stockages est un préalable à la mise en œuvre des tels sites. Dans ce cadre, une méthodologie de monitoring géochimique combinant la géochimie des gaz rares et des isotopes du carbone a été testée sur des analogues naturels et industriels. Sur les analogues naturels de contextes géologiques variés, des comportements systématiques des paramètres géochimiques en fonction du confinement des sites ont pu être révélés, attestant de l’efficacité de ces outils en termes de détection des fuites et en tant que traceurs du comportement du CO2 dans les futurs sites de stockage. De plus, une expérience de traçage géochimique sur un stockage de gaz naturel a démontré qu’il est possible d’identifier les processus physico-chimiques se déroulant dans le réservoir à l’échelle humaine, renforçant l’intérêt pour l’outil proposé et apportant des informations méthodologiques sur son utilisationTo limit emissions of greenhouse gases in the atmosphere, CO2 geological sequestration appears as a solution in the fight against climate change. The development of reliable monitoring tools to ensure the sustainability and the safety of geological storage is a prerequisite for the implementation of such sites. In this framework, a geochemical method using noble gas and carbon isotopes geochemistry has been tested on natural and industrial analogues. The study of natural analogues from different geological settings showed systematic behaviours of the geochemical parameters, depending on the containment sites, and proving the effectiveness of these tools in terms of leak detection and as tracers of the behaviour of CO2. Moreover, an experience of geochemical tracing on a natural gas storage has demonstrated that it is possible to identify the physical-chemical processes taking place in the reservoir to a human time scale, increasing interest in the proposed tool and providing general informations on its use
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Zamagni, Lisa, Chiara Bartolini, and Mariotti Rondoni Marco Santos. "Novae Latomie Veteres. Il paesaggio tra sottrazione e addizione: studi per la riconversione delle cave di travertino nella piana del medio Aniene a Tivoli." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2019. http://amslaurea.unibo.it/18207/.
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NOVAE LATOMIE VETERES
IL PAESAGGIO TRA SOTTRAZIONE E ADDIZIONE
STUDI PER LA RICONVERSIONE DELLE CAVE DI TRAVERTINO NELLA PIANA DEL MEDIO ANIENE A TIVOLI
Nell’area del giacimento dei travertini che, attualmente ricopre circa 20 km quadrati, sono visibili sempre più frequentemente nuove cave dismesse o in via di esaurimento. A questo punto, quindi, è bene porre all’attenzione di tutti il delicato problema della riqualificazione e della valorizzazione di un intero territorio, effettuato attraverso un risanamento ambientale e un intervento di restauro paesaggistico. La salvaguardia della “Natura” dei luoghi, ossia la riscoperta del Genius Loci, che l’ambiente riassume in sé. Un rapporto complesso quindi, quello tra uomo e natura che può e, anzi, deve trovare un punto di dialogo e di raccordo.
Per questo motivo solo l’accurata conoscenza del sito e il rispetto per il lavoro e la storia delle comunità possono portare alla formulazione di un linguaggio atto all’individuazione di possibilità di sviluppo per il futuro, salvaguardando gli aspetti caratteristici.
Inoltre, la coscienza delle proprietà peculiari di questo luogo, potrà maturare una proposta di intervento volto a definire il paesaggio funzionale a rievocare le sensazioni e suggestioni, in una forma del tutto rinnovata, di quel quadro naturale tanto caro ai viaggiatori del passato.
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Ali, Ahmed Adam. "Les systèmes travertineux holocènes et la caractérisation des paléopaysages méditerranéens et subalpins (France) : une approche géobotanique séquentielle à haute résolution spatiale." Montpellier 2, 2003. http://www.theses.fr/2003MON20094.
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Verasani, Beatrice. "Studio e caratterizzazione dei materiali di rivestimento e del loro degrado ai fini del restauro dell'ex-Casa del Fascio di Predappio (FC)." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2021.
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La ex-Casa del Fascio di Predappio (FC) è uno dei monumenti simbolo dell’architettura razionalista italiana, portatrice non solo dei caratteri fondamentali di uno stile architettonico, ma anche della cultura del tempo e delle tecniche costruttive degli inizi del Novecento. È dunque chiaro il motivo per il quale il restauro di tale monumento richieda attenzione per ogni singolo dettaglio, oltre a rappresentare un importante momento di ricerca nell’ambito della conservazione degli edifici del ventesimo secolo. Lo stato di abbandono in cui versa l’edificio perdura da quasi trent’anni ed ha portato ad un inesorabile avanzamento dei fenomeni di degrado in atto. I rivestimenti esterni dell’edificio consistono nell’accostamento di un materiale tipico della tradizione architettonica italiana, ovvero il travertino, e di un materiale innovativo brevettato pochi anni prima della costruzione stessa della ex-Casa del Fascio, ossia l’Italklinker. Nell’ambito di questo elaborato è stata sviluppata una ricerca mediante indagini di laboratorio per stabilire lo stato di avanzamento del degrado di tali rivestimenti, con lo scopo di fornire informazioni utili al gruppo di progettisti incaricati del restauro. I risultati ottenuti hanno evidenziato come per i materiali di finitura sia interni che esterni siano necessari ingenti interventi di restauro volti a bloccare i processi di degrado in corso, da integrare in un apposito progetto. In particolare, gli interventi risultano essere particolarmente complessi per i rivestimenti esterni. Per le lastre in travertino, infatti, si rende necessario intervenire puntualmente con perni metallici e malta di ripristino, approccio che non può essere applicato per i listelli di Italklinker, vista la ridotta dimensione degli elementi e l’estensione stessa delle tamponature. Per quest’ultimi dev’essere pertanto pensata una soluzione che permetta di agire direttamente sulle superfici e non in modo specifico per ogni componente.
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Laouina, Abdellah. "Le Maroc nord-oriental : reliefs, modèles et dynamique du calcaire." Paris 1, 1987. http://www.theses.fr/1987PA010681.
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Le maroc nord-oriental appartient a l'alignement montagneux du rif-tell bordant la mediterrannee. Mais il s'en differencie par un relief cloisonne, une structure de nature atlasique, des conditions climatiques a tendance aride et des modeles inhabituels en region seche, caracterises par une etonnante regularite des pentes et une faible expression de la variete structurale et lithologique. Les plans alluviaux et de piemont, ainsi que les versants, meme en plein domaine montagneux sont caracterises par la generalite des accumulations carbonatees sous la forme de travertins, de colluvions cimentees et de croutes calcaires. Celles-ci sont toujous paralleles aux formes du modele et par contre discordantes par rapport aux formations superficielles qu'elles impregnent. Grace a de nombreuses methodes d'analyse et d'observation, il a ete demontre que des relations etroites existent entre l'evolution discrete des versants, caracterises par une certaine stabilite et une grande regularite et la dynamique du calcaire qui indique une interference continue entre phenomenes de decalcification et processus de precipitation et d'accumulation.
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Monteiro, Ana Isabel Mourão. "Caracterização e otimização do polimento de grés porcelânico." Master's thesis, Universidade de Aveiro, 2013. http://hdl.handle.net/10773/12362.
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Mestrado em Engenharia de MateriaisEste trabalho teve como objetivo o estudo do processo de polimento em produtos de grés porcelânico da empresa Revigrés. O polimento é um processo que melhora as características estéticas da superfície da peça, aproximando desta forma a sua aparência às pedras naturais. Durante as três etapas de polimento, foi feito um estudo sistemático da caracterização estrutural, microestrutural e das propriedades dos produtos polidos, para se entender que fenómenos acontecem em cada uma destas etapas e encontrar soluções para os problemas descobertos. A primeira etapa é a de calibração que tem como finalidade planificar a superfície. Esta danifica fortemente a superfície induzindo defeitos que são irrecuperáveis com as etapas seguintes. As seguintes etapas eliminam os riscos, tornam a superfície uniforme e conferem brilho. Os defeitos incitados provocam uma diminuição da resistência às manchas. Por forma a contornar o problema a empresa coloca uma cera impermeabilizante na superfície da peça polida. De forma a diagnosticar o problema na qualidade da superfície polida, foi eliminada a etapa de calibração no processo de polimento das peças de grés porcelânico técnico e conclui-se que a supressão desta etapa mantem as propriedades técnicas, como a absorção de água e a porosidade aparente, mas piora os atributos estéticos. Como soluções foi sugerido, fazer alterações no abrasivo usado de forma a não danificar tanto a superfície, ou eliminar a etapa de calibração e melhorar as restantes.
The current work aims at studying the polishing process of porcelain tiles from Revigrés Company. Polishing is a process that enhances the esthetic characteristics of the surface of the ceramic pieces, by achieving a higher resemblance to the natural stones. During the three stages of the polishing procedure, a systematic study of the ceramic pieces was followed, concerning the structural and microstructural properties of the polished products, in order to understand the effect of each stage and come up with solutions for the occurring problems. The first stage is the calibration stage, which aims at flattening the surface. This stage highly damages the surface, inducing defects that are irrecoverable after the succeeding stages. The following steps eliminate the scratches, making the surface more uniform and confer brightness. The induced defects provoke decrease of the stain resistance. In order to resolve this problem, the company’s strategy is the application of a waterproof wax on the surface of the polished piece. In order to diagnose the problem on the quality of the polished surface, the calibration stage of the polishing process of the technical porcelain samples was omitted and it was concluded that the elimination of this stage maintains the technical properties, such as water absorption and apparent porosity, however it deteriorates the esthetical attribute. The suggested solutions are modifications of the utilized abrasive, in order to avoid excessive damaging of the surface, or elimination of the calibration stage and enhancement of the next stages.
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Jeandel, Elodie. "Monitoring géochimique par couplage entre les gaz rares et les isotopes du carbone : étude d'un réservoir naturel." Phd thesis, Université Paris Sud - Paris XI, 2008. http://tel.archives-ouvertes.fr/tel-00399871.
Full textAbstract:
Dans un objectif de limitation des émissions de gaz à effet de serre dans l'atmosphère, la séquestration géologique du CO2 apparait comme une solution incontournable pour lutter contre le changement climatique.Le développement d'outils de surveillance fiables pour s'assurer de la pérennité et de la sécurité des stockages est un préalable à la mise en œuvre des tels sites.
Dans ce cadre, une méthodologie de monitoring géochimique combinant la géochimie des gaz rares et des isotopes du carbone a été testée sur des analogues naturels et industriels.
Sur les analogues naturels de contextes géologiques variés, des comportements systématiques des paramètres géochimiques en fonction du confinement des sites ont pu être révélés, attestant de l'efficacité de ces outils en termes de détection des fuites et en tant que traceurs du comportement du CO2 dans les futurs sites de stockage.
De plus, une expérience de traçage géochimique sur un stockage de gaz naturel a démontré qu'il est possible d'identifier les processus physico-chimiques se déroulant dans le réservoir à l'échelle humaine, renforçant l'intérêt pour l'outil proposé et apportant des informations méthodologiques sur son utilisation.
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Pola, Marco. "Revisione del modello idrotermale del bacino termale euganeo alla luce delle nuove conoscenze in ambito idrogeologico e geologico strutturale." Doctoral thesis, Università degli studi di Padova, 2012. http://hdl.handle.net/11577/3422516.
Full textAbstract:
The Euganean geothermal field (EGF) is the most important thermal field in the northern Italy. It is located in the Veneto alluvial plain, southwest of Padova (NE Italy), close to the northeast margin of the Euganei Hills. The aim of the PhD thesis is to review the hydrothermal model of the thermal system, using the new knowledge in structural geology and hydrogeology. The proposed hydrothermal model emphasises the role that one of the most important regional geological structure, i.e. the Schio–Vicenza fault system (SVFS), plays in the flow of thermal waters from the recharge area to the EGF area. In fact, the EGF is located along the SVFS, where the main segment changes its direction allowing a local extensional strain. The Schio-Vicenza fault channelizes and enhances the quick uprising of the thermal waters in EGF, thanks to the local extensional regime caused by a transtensional relay zone linked to two different segment of the fault. The recharge area is located to the east of the Schio-Vicenza fault, in Tonezza and Sette Comuni plateau area, instead of to the west (Piccole Dolomiti area) like in the previous conceptual model.
The SVFS architecture was reviewed using a collection of seismic lines and gravimetric maps, allowing a broad vision of the fault system. It extends from the Schio area to the Po delta and is composed mainly by three NE-dipping high angle faults (Schio-Vicenza fault, Conselve-Pomposa fault and Travettore-Codevigo fault) with a main NNW-SSE trend. The analysis of the seismic lines evidences also their polyphase activity, started during the Mesozoic to Paleogene extension and continued until present. A 3D model from five interpreted seismic lines was performed to obtain a broad vision of the subsurface geology near the Euganei Hills. A structural study was performed in the northern part of the fault system, giving evidence of a transtensional regime.
A 5 meter high travertine hill (Montirone Hill-Abano Terme), affected by a network of fractures mainly WNW-ESE trending, in the EGF area is studied for the first time during the Ph.D. thesis using a multidisciplinary approach (sedimentology, structural geology, geochemistry, geophysics). The hill is classified as a travertine mound (because of its shape and the sedimentological study performed analysing about 30 thin sections of travertine) and the travertine has an age from 30±4 kY to 25±5 kY (dated using U/Th series isotopes). The presence of a travertine hill is an important constraint for the extensional regime that acts in the EGF area and supports the existence of a relay zone buried beneath the alluvial cover.
Finally, a mathematical hydrothermal model of the EGF was developed, starting from the proposed conceptual model, using the software Hydrotherm (Kipp et al., 2008). Hydrotherm simulates thermal energy transport in three-dimensional, two-phase, hydrothermal, ground-water flow systems. First of all, sets of simulations were performed to understand better the different type of boundary conditions to simulate the flow in the EGF area: the best results were obtained using a seepage face in the EGF area that could simulate the extensional regime, evidenced by structural study, enhancing the outflow of thermal waters. Simulations by the use of different rock-parameters (mainly permeability and thermal conductivity) were performed to understand how the permeability and thermal conductivity of the rocks could affect the temperature in the subsurface of the EGF. Topography-driven flow is retarded by low permeability of the main thermal aquifer and also difference using different thermal conductivity (low for the thermal aquifer and high for the formation below the thermal aquifer) is depicted .Il Bacino Termale Euganeo (BTE) è uno dei sistemi termali più importanti del nord Italia ed è localizzato nel Veneto centrale, a Sud di Padova e ad Est dei colli Euganei. Lo scopo del lavoro di dottorato è stato quello di aggiornare il modello idrotermale del BTE alla luce delle nuove conoscenze geologico strutturali e idrogeologiche acquisite nel corso del lavoro di dottorato e negli ultimi 30 anni. Il modello idrotermale proposto enfatizza il ruolo che i sistemi di faglie attive del Veneto centrale hanno nello sviluppo del BTE. In particolare si è osservato che il BTE è localizzato in prossimità di una struttura di interazione fra le faglie del sistema Schio-Vicenza (SVFS) che accomoda un regime distensivo locale. Questa struttura incremente la fratturazione/permeabilità del substrato e favorisce la rapida risalita dei fluidi termali dal sottosuolo. L'architettura del SVFS è stata reintrerpretata nel lavoro di dottorato grazie ad un'analisi accurata di dati pubblicati e non. In particolare si è osservato che il SVFS è costituito da un fascio di faglie con direzione media NO-SE/NNO-SSE che si estende dal delta del Po fino alla zona di Schio. L'analisi delle sezioni sismiche ha evidenziato un'attività polifasica del SVFS iniziata probabilmente nel Mesozoico e che prosegue a tutt'ora. Un'informazione importante riguardo al regime tettonico in atto nel BTE è stata ottenuta dallo studio effettuato sul colle del Montirone in Abano Terme. Il colle è studiato per la prima volta in maniera scientificamente moderna mediante un approccio multi-disciplinare (analisi sedimentologiche, analisi geochimiche, analisi geologico-strutturali, analisi geofisiche). Il deposito è stato interpretato come un regular shaped travertine mound (come confermato dall'analisi sedimentologica effettuata su circa 30 sezioni sottili di travertino) ed è stato datato, mediante datazioni U/Th, a 25-30 mila anni fa. Questo dimostra un lungo tempo di attività del BTE. Il modello idrotermale concettuale proposto localizza la zona di ricarica del BTE nell'altopiano dei Sette Comuni e Tonezza e nei rilievi limitrofi. Le acque precipitano e si infiltrano grazie all'elevata fratturazione delle rocce affioranti, fluiscono all'interno della zona di danneggiamento del SVFS ed infine nella zona di Abano Terme vengono intercettata dalla zona di interazione fra le faglie del SVFS che favorisce la rapida risalita dei fluidi termali. Il modello concettuale è stato implementato nel software HYDROTHERM che permette di simulare il trasporto di fludi termali in sistemi multi-fase. Inizialmente sono state scelte le condizioni iniziali e al contorno più adatte per permettere lo sviluppo del flusso termale. In particolare, la scelta di una condizione al controno di seepage face nella zona del BTE permette una risalita naturale dei fluidi termali. Successivamente le simulazioni sono proseguite con un'analisi di sensitivà riguardo ai valori migliori dei parametri da usare per permettere lo sviluppo della temperatura e del flusso nel sottosuolo del BTE. Si è dimostrato cosi che il flusso di fluidi termali è fortemente influenzato dall'utilizzo di valori mirati di permeabilità (in particolare l'utilizzo di una configurazione anisotropa di permeabilità) e conducibilità termica (valori bassi per le formazioni dell'acquifero termale principale e alti per le formazioni sottostanti).
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Ambert, Paul. "L'évolution géomorphologique du Languedoc central (grands causses méridionaux-Piémont languedocien) depuis le néogène." Aix-Marseille 2, 1991. http://www.theses.fr/1991AIX23002.
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L'étude des volcans et des travertins de la vallée du Tarn, comparée avec celles des formations volcaniques plio-pleistocène de l'Escandorgue, et celle des dépôts néogènes du piemont du Languedoc central donnent une information précise sur l'évolution des Causses méridionaux et du Languedoc central depuis le Néogène. Sur le plateau du Larzac, les reliefs dolomitiques débarassés de leurs altérites sont ennoyés par les laves. Cet état de fait s'accorde avec la reconnaissance de vallées régionales pré-quaternaires dont le creusement dépasse très largement celui qui revient en propre aux morphogénèses postèrieures (vallées de Bernasso, vallee du Tarn). Aussi c'est au Néogene que nous situerons la phase de karstification responsable de l'élaboration des paysages caussenards. Le début de l'incision des gorges ressort probablement du Miocène moyen. Elle peut être corrélée avec le Miocène moyen qui enregistre pour la premiere fois dans le Bas Languedoc les apports directs des quartz des Cévennes dans la mer miocène. L'évolution quaternaire est déduite de l'étude des terrasses alluviales des principales vallees (Hérault, Orb, Aude) ? De leurs relations avec le volcanisme, les lignes de rivage et les formations éoliennes. Les principaux résultats de l'évolution holocène sont présentésThe study of Tarn volcanoes and travertines, comparitive study of Escandorgue plio-pleistocene volcanic formations and neogene deposits of languedocian central piemont give a precise and complete informations of southern "grands causses" and languedocian evolution since the neogene. In larzac plateau - north escandorgue - the dolomitics monoliths well cleaned of their alterits are fossilized by lavas. This situation fuly agrees with the existence of regional pre-quater- nary valleys whose deepening is more important than the one that belongs to later morphogenesis (bernasso valleys, tarn valley). After all, the most important karstification phase dates back to neo -gene. It is responsible for the elaboration of the causses landscape the canyon incision initiation which is most probably middle miocene. It may be corraleted to languedocian miocene? Which records the first directs deposits from the cevennes quartz pebbles in the languedocian miocene sea. Quaternary evolution is also studied in terraces valleys (herault, orb, aude rivers) their relations with quaternary shorelines and eolians formations. Holocenic times are presented
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Ollivier, Vincent. "Continuités, instabilités et ruptures morphogéniques en Provence depuis la dernière glaciation.Travertinisation, détritisme et incisions sur le piémont sud du Grand Luberon (Vaucluse, France). Relations avec les changements climatiques et l'anthropisation." Phd thesis, Université de Provence - Aix-Marseille I, 2006. http://tel.archives-ouvertes.fr/tel-00360109.
Full textAbstract:
L'évolution des paysages provençaux (sud Luberon, Vaucluse, France) depuis la dernière glaciation est analysée au travers de la dynamique couplée des formations alluviales et des systèmes travertineux, en relation avec les changements climatiques et l'anthropisation. Des analyses géomorphologiques, sedimento-stratigraphiques et physico-chimiques, dont les résultats sont incrémentés par des études archéologiques et paléoécologiques (malacologie et anthracologie) ainsi qu'une cinquantaine de datations 14C, constituent les fondements d'une étude à vocation pluridisciplinaire sur les relations Homme/milieu en France méditerranéenne.Aux environs de 50 Ka BP, les vallons du piémont sud du Grand Luberon sont colmatés par de puissants glacis d'accumulation dépassant fréquemment les 30 mètres d'épaisseur et remaniant un abondant matériel torrentiel caillouteux contenant des gélifracts. A leur base, plusieurs « sols rouges » et leur contenu paléontologique, indiquent le caractère plus tempéré des épisodes interstadiaires du Stade Isotopique 3 en domaine méditerranéen.
Entre le Dernier Maximum Glaciaire et le Tardiglaciaire (18000-17000 cal BP. ?), période charnière au niveau bioclimatique, une incision majeure intervient, surprenante par son ampleur et sa rapidité. Dès 15500 cal. BP, la tendance morphogénique s'inverse et l'on assiste à une reprise de l'accumulation sédimentaire dans les fonds de vallons. Au sein de cette nouvelle dynamique, de puissantes formations travertineuses se développent aux débouchés d'exsurgences karstiques et signent le réchauffement climatique engagé. Celles-ci constituent jusqu'à présent le plus ancien témoignage du « redémarrage » postglaciaire de la travertinisation dans le sud de la France. Par la suite, et dans l'ensemble des formations détritiques et carbonatées, deux incisions principales se produisent vers 9000 et 6000 cal. BP en alternance avec des phases de remblaiements. Les fluctuations morphogéniques de cette première partie du Postglaciaire s'accordent, et semblent principalement inféodées, aux variations des paramètres bioclimatiques.
Dès le Néolithique Final, dans un contexte d'augmentation des occupations humaines, les séquences enregistrent une série de ruptures (incisions) de haute fréquence et de faible amplitude. Ces perturbations sont accompagnées de changements de faciès dans les systèmes carbonatés et d'ouvertures fortes du milieu végétal déterminées par les analyses paléoécologiques. Le caractère particulièrement sensible des ensembles travertineux aux modifications d'origine climato-anthropique du biotope est ainsi souligné.
Entre le XIème et le XIIIème siècle après Jésus Christ, on note l'interruption, de l'accumulation des travertins et le démantèlement des formations l.s. (et non entre la fin du Néolithique et la période antique comme il était communément admis). C'est également dans le même intervalle que s'instaure la dynamique majeure d'incision linéaire des talwegs bien connue dans le sud de la France, mais jusqu'à présent rangée dans une chronologie incertaine. Postérieurement au XVIIème siècle, au cours du Petit Age Glaciaire, une dernière période de remblaiement détritique plus modeste débute. A terme, celle-ci est interrompue par une ultime phase d'incision toujours effective aujourd'hui. L'action conjuguée des oscillations climatiques et des modes d'occupation des sociétés humaines sur le milieu « naturel » apparaît comme le principal moteur d'une morphogenèse mouvementée au cours de la deuxième partie du Postglaciaire.
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Cueto, Mendoza Nora. "Principales factores de control de las propiedades de transporte de fluidos en rocas carbonáticas marinas y continentales: Estudio experimental y teórico integrado sobre la relación entre la permeabilidad y la capilaridad." Doctoral thesis, Universidad de Alicante, 2020. http://hdl.handle.net/10045/114153.
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La predicción de las propiedades de transporte de fluidos es una labor de importancia primordial en áreas científicas de gran interés económico. Las dificultades encontradas en describir y predecir cualquier problema ingenieril relacionado con el flujo de fluidos en medios rocosos carbonáticos es un desafío compartido entre los investigadores dedicados a este tema, atribuido principalmente al gran número de variables a ser consideradas. Las texturas de origen primario y secundario, la composición mineralógica, la porosidad y la distribución de tamaño de poro, la proporción clasto/matriz/cemento/tipo de poro, el arreglo espacial de los elementos texturales y estructurales, entre otros, actúan simultáneamente a escala de poro hasta escalas superiores, impactando sobre un único parámetro de conjunto investigado. Como resultado, los modelos de predicción clásicos no describen correctamente las propiedades de transporte de fluidos, debido a la pobre relación encontrada entre los resultados experimentales y las estimaciones teóricas. Esto podría deberse, en parte, a la exclusión de parámetros claves en las teorías existentes, a la simplificación excesiva de las ecuaciones generalizadas y a la aplicación inadecuada de modelos determinísticos para evaluar medios porosos caóticos. Esta investigación tiene como objetivo desarrollar modelos de flujo monofásico en rocas carbonáticas de agua dulce y marinas, con el propósito de describir procesos de flujo reales, tanto en medios no saturados (capilaridad) como saturados (permeabilidad), a partir de un enfoque teórico y experimental. Para ello, primero se cuantifican en profundidad los factores intrínsecos de las rocas y posteriormente se determina su control sinérgico sobre el comportamiento del flujo de fluidos. Con base en la conceptualización adecuada del espacio poroso interconectado, como también en la selección y parametrización de las variables petrológicas y petrofísicas más significativas, se introducen nuevas ecuaciones empíricas de regresión lineal múltiple y soluciones semi-analíticas para estimar la permeabilidad. La atención se centra en modelos de predicción de la permeabilidad a partir de la imbibición capilar, la estructura del poro y la mojabilidad, asumiendo que el frente capilar en el ensayo de imbibición espontánea alcanza un estado de saturación completa como el presentado en la permeabilidad absoluta. En esta investigación se escogieron tres tipos de dolomías fracturadas y dos travertinos de la Cordillera Bética (SE de España), y una caliza lacustre de la Cuenca de Madrid (Centro de España), comercializadas como mármoles y ampliamente utilizadas como material de construcción. A fin de verificar los modelos de permeabilidad e identificar los principales factores de control, también se estudiaron y se compararon algunas rocas sedimentarias adicionales provenientes de España (biocalcarenita, biocalcirrudita, oosparita y arenisca) y dos rocas volcánicas (tobas de lapilli) de la Isla de Madeira, Portugal. En conjunto, estas rocas además de presentar una petrogénesis y composición mineralógica diferenciada, también exhiben una amplia gama de características petrográficas que proporcionan distintos grados de conectividad, porosidades, distribuciones de tamaño de poro, coeficientes de absorción de agua por capilaridad y de permeabilidades al agua. El análisis de componentes principales y los modelos de regresión propuestos para las dolomías fracturadas demostraron claramente, por un lado, que el sistema poroso en medios no saturados debe ser modelado a partir de la combinación de tubos capilares con geometría diferente representando la matriz (cilíndricos) y las fisuras (prismas rectangulares) y, por otro lado, que la cuantificación detallada del tamaño de la fisura permitió una predicción más precisa de la permeabilidad en medios saturados. Los resultados experimentales confirman que las propiedades de transporte y su comportamiento anisotrópico dependen en gran medida de la tipología de las fisuras, de las características texturales, de la mineralogía y de la distribución espacial de todos los elementos constituyentes de la fábrica de la roca. Las fisuras con gran apertura generan una succión capilar débil, por lo que no se hallan activas en el transporte de agua por capilaridad, pero son vitales para controlar la permeabilidad. Las brechas tipo «crackle» con clastos pequeños, alto contenido de cemento dolomítico y alta densidad de fisura de tipo interclasto, muestran una fuerte succión capilar. Sin embargo, el alto contenido de cemento calcítico produce tasas anormalmente bajas del ascenso capilar, causadas por una posible contaminación de la superficie de los poros, indicando un estado de mojabilidad parcial con un ángulo de contacto mayor que cero. La buena correlación entre la permeabilidad y los factores geométricos de la fisura ofreció una base adecuada para identificar direcciones permeables preferentes. Adicionalmente, se encontró un valor de densidad de fisura crítica (umbral de percolación) que definió la permeabilidad isotrópica de la matriz. Finalmente, se presenta un nuevo modelo lineal práctico y simple, aplicable a dolomías brechoides, que relaciona la permeabilidad con la capilaridad, la densidad de fisura y la porosidad efectiva. El análisis de estos resultados reveló que el uso del análisis multivariante en dolomías con porosidad de tipo dual es considerablemente más preciso en comparación con los enfoques convencionales. El espacio poroso de las calizas, travertinos, tobas, rocas bioclásticas y areniscas estudiadas se describe como un medio poroso homogéneo constituido por un grupo de tubos capilares paralelos. El análisis estadístico también mostró fuertes correlaciones entre los parámetros petrofísicos de las variedades petrológicas evaluadas. Diversas propiedades fundamentales se ajustan a diferentes expresiones lineales y múltiples, en las cuales la permeabilidad al agua se expresa como una función generalizada de las propiedades. La relación entre la permeabilidad y la porosidad se discute en el contexto de la influencia de la conectividad de los poros y la mojabilidad. Como consecuencia, se propone un modelo generalizado para estimar la permeabilidad en medios porosos homogéneos que incluye información sobre la tasa de fluidos del agua (coeficiente de absorción capilar), propiedades del agua (densidad y viscosidad), mojabilidad (tensión interfacial y ángulo de contacto) y estructura del poro (radio medio del poro y porosidad). Los resultados indican que el radio de poro umbral, en el que el agua percola a través de la roca, logra la mejor descripción del sistema poroso. La ecuación propuesta se compara con las ecuaciones de Carman-Kozeny y Katz- Thompson y alcanza predicciones muy precisas de la permeabilidad al agua en el rango de 0.01 a 1000 mD. Otro aspecto significativo de esta ecuación consiste en el hecho de que reveló que valores altos de ángulos de contacto permiten obtener resultados confiables en la predicción de la permeabilidad, especialmente en rocas con alto contenido de calcita. Por tanto, se propone una ecuación para estimar la permeabilidad a partir de la sortividad intrínseca en lugar de la capilaridad, eliminando la existencia de cualquier estado de mojabilidad parcial y logrando así una excelente correlación entre los resultados predichos y los experimentales. Una regresión lineal simple que relaciona el coeficiente de absorción capilar con la raíz cuadrada de la permeabilidad, proporcionando por primera vez un alto coeficiente de correlación (R = 0.991) en rocas altamente heterogéneas y anisotrópicas, específicamente en tobas de lapilli, sugiere que en ausencia de calcita no se espera una absorción anormal de agua por capilaridad y, por consiguiente, este tipo de modelo podría aplicarse de manera muy efectiva en estos casos. En resumen, este estudio ha demostrado que a través de la implementación de un enfoque sistemático que incluye la configuración real del sistema poroso de la roca, la identificación correcta de las variables petrológicas y petrofísicas relacionadas directamente entre sí, la determinación de su efecto sinérgico y, finalmente, la elección adecuada del modelo de permeabilidad a ser aplicado, es factible obtener estimaciones precisas de la permeabilidad.
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Delannoy, Jean-Jacques. "Recherches géomorphologiques sur les massifs karstiques du Vercors et de la transversale de Ronda (Andalousie) : les apports morphogéniques du karst." Phd thesis, Grenoble 1, 1997. http://tel.archives-ouvertes.fr/tel-00691560.
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Le principal objet de cette thèse est de montrer que le karst est un vecteur pertinent d'informations morpho géniques. Pour utiliser à bon escient ce vecteur, il est nécessaire d'avoir une bonne connaissance des paramètres intervenant dans la formation et la structuration des vides endokarstiques et sur les processus de sédimentation carbonatée (spéléothème et travertin). Ces paramètres sont abordés, dans le Livre l, au travers de l'approche systémique. Cette approche apparaîtt la plus appropriée pour, d'une part, aborder les notions de structure, de flux et d'évolution du système karstique et, d'autre part, pour définir des stratégies méthodologiques cohérentes. Sur la base de cette approche, deux domaines géographiques ont été traités: le Vercors (Livre II) et la Transversale de Ronda (Livre III). L'intérêt de travailler sur deux entités différentes est double: il permet de s'affranchir des spécificités locales qui ont, parfois, pour effet de parasiter les essais morphogéniques ; le second intérêt est de pouvoir déterminer les différentes réponses du karst aux événements d'ordre tectonique, eustatique et/ou climatique. L'étude du karst, comme vecteur d'informations, a permis de définir la part d'événements dans l'évolution morphologique de ces deux domaines, comme la crise messinienne, le soulèvement pliocène et les oscillations climatiques pléistocènes, dont les effets n'étaient pas toujours perceptibles à partir des seules données superficielles. De ce travail, il ressort que les paléodrains constituent l'une des entrées les plus pertinentes car ils permettent de saisir l'existence de structures de substitution induites par des événements paléogéographiques de "premier ordre".
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Lyzhanov, Iurii. "Architektonická studie sakrálního objektu a komunitního centra Salesiánského Brno - Líšeň / druhá etapa." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2021. http://www.nusl.cz/ntk/nusl-443691.
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The main task of diploma is creating a sacral object and community centre of Salesians in Brno-Líšeň. A construction of the Salesian complex started in 1998. As a result, the whole complex of institution got to the district of Brno-Lisen with the help of the endowment fund for youth. The Congregation focuses on the methods of educating the youth of Don Bosco, the father and teacher of the youth, the first head of the Salesian. The creation of a church is a very desirable step for the Salesian Center, because Masses are currently being celebrated in the existing building in the gym, where not everything is needed to carry out of the event. The church should be developed in the vicinity of Salesian centre and has to be available for a wide range of societies. The architectural project includes the designing of church, parish building and enviroment. The form and view of the complex suit to this environmental area and react on its entire structure. The object consists of two forms, which are connected by the horizontal communication. In the middle of the Salesian complex, there is a semi-open area. The first object is a church with a capacity of approximately 200 hundred visitors, the second object is a parish building, which perform the functions of administration with multifunction space for the exhibitions, aparmtments and offices for its employees.
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Lin, Chi-Lieh, and 林基烈. "Study on the diatoms of the travertine springs in Taiwan." Thesis, 1996. http://ndltd.ncl.edu.tw/handle/59224132563820470930.
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碩士國立中興大學
植物學系
84
A study on the diatoms of the travertine springs in Taiwan was conducted from March 1995 to November 1995. Twenty-one springs were visited and diatoms samples from thirty-eight stations were collected. Seventy-five species and thirteen additional varieties in twenty-three genera have been identified, including ten species of Achnanthes, two species of Amphora and Caloneis, one species of Grammatophora, Cocconeis, Denticula and Cyclotella, fourteen species of Cymbella, two species of Diatoma, four species of Diploneis, five species of Eunotia, two species of Epithemia, Fragilaria and Hantzschia, five species of Melosira and Nitzschia, three species of Surirella, seven species of Gomphonema and Navicula, four species of Synedra, six species of Pinnularia, one species of Rhopalodia and Stauroneis. The description and illustrations of each diatoms are given. Cluster analysis was used on the basis of presence absence data to define the relationship between diatom taxa and different dissolved CO2 gas content. The twenty-three genera of diatoms can be divided into eight groups, and the eighty-eight species of diatoms can be divide into fifteen groups. Using the same method to define the relationship between diatom taxa and water temperature, the twenty-three genera of diatoms can be divided into ten groups, and the eighty-eight species of diatoms can be divided into nineteen groups. However, from cluster analysis the sampling stations of hot spring showed no obviously group of diatom taxa in the dendrogram. Navicula tripunctata and Nitzschia palea can be found throughout the study area with different CO2 gas content and water temperature. It can be considered that these two species of diatoms were tolerant species to CO2 gas content and water temperature of the environment. Diatom communities inhabiting the travertine springs in Taiwan possess similarities with which inhabiting hot springs in other countries. Especially, Achnanthes exigua, Amphora ovalis and Cymbella affinis have been found all over the world.
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Fiser, Julie. "Organic biomarkers in active and fossil travertine deposits linking the present with the past /." 2008. http://purl.galileo.usg.edu/uga%5Fetd/fiser%5Fjulie%5Fm%5F200805%5Fms.
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Jorge, Villar Susana E., L. G. Benning, Howell G. M. Edwards, and AMASE team. "Raman and SEM analysis of a biocolonised hot spring travertine terrace in Svalbard, Norway." 2007. http://hdl.handle.net/10454/2305.
Full textAbstract:
A profile across 8 layers from a fossil travertine terrace from a low temperature geothermal spring located in Svalbard, Norway has been studied using both Raman spectroscopy and SEM (Scanning Electron Microscopy) techniques to identify minerals and organic life signals.
Calcite, anatase, quartz, haematite, magnetite and graphite as well as scytonemin, three different carotenoids, chlorophyll and a chlorophyll-like compound were identified as geo- and biosignatures respectively, using 785 and/or 514 nm Raman laser excitation wavelengths. No morphological biosignatures representing remnant microbial signals were detected by high-resolution imaging, although spectral analyses indicated the presence of organics. In contrast, in all layers, Raman spectra identified a series of different organic pigments indicating little to no degradation or change of the organic signatures and thus indicating the preservation of fossil biomarker compounds throughout the life time of the springs despite the lack of remnant morphological indicators.
With a view towards planetary exploration we discuss the implications of the differences in Raman band intensities observed when spectra were collected with the different laser excitations. We show that these differences, as well as the different detection capability of the 785 and 514 nm laser, could lead to ambiguous compound identification. We show that the identification of bio and geosignatures, as well as fossil organic pigments, using Raman spectroscopy is possible. These results are relevant since both lasers have been considered for miniaturized Raman spectrometers for planetary exploration.