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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
141

Archaeological Explorations in Caves of the Point of Pines Region, Arizona

Gifford, James C. January 1980 (has links)
"The volume contains a wealth of ceramic type-variety descriptive and interpretive data, as well as an excellent descriptive treatment of the ethnobotanical remains, and solid coverage of the lithic, faunal, and other classes of artifactual materials. The quality of illustrative material is excellent, including outstanding field and artifact photography and carefully prepared charts and line drawings."—American Antiquity
142

Approche techno-économique des industries lithiques des grottes de la Terrasse, de Coupe-Gorge, de la Niche, Boule et des Putois, à Montmaurin (Haute- Garonne), France et potentiel d'application sur quelques sites sénégalais. / Techno-economic approach of the lithic industries of the caves of the Terrasse, Coupe-Gorge, Niche, Boule and Putois, to Montmaurin (Haute-Garonne), France and potential of application on some senegalese sites.

Thiam, Djibril 17 September 2018 (has links)
L'imposant réseau karstique de Montmaurin situé à l’extrémité occidentale du chaînon des Petites Pyrénées, renfermait plusieurs grottes. Aujourd'hui, seulement huit cavités ont échappé à l'exploitation des carriers. Malgré la dispersion des collections, l’industrie lithique des fouilles de L. Méroc et R. Cammas (1946-1962) dans les grottes de Montmaurin a pu bénéficier d’un inventaire et de l’étude de l’intégralité des niveaux acheuléens et moustériens. L’étude techno-typologique et pétroarchéologique menée lors de ce travail de recherche montrent des spécificités inhérentes aux grottes de Montmaurin. Les caractéristiques de ce que nous proposons de nommer « le complexe de Montmaurin » dégage une spécificité dans les contreforts pyrénéens. Ce « complexe » possède une certaine unité typologique et technologique. Le cortège lithologique est composé de galets de quartzite de lydienne de quartz etc. qui proviennent des affluents de la Garonne et de silex pré-pyrénéen. Les territoires d’acquisition des ressources minérales sont plus ou moins vastes, d'une centaine de mètres à environ 80 kilomètres. L'application de la méthode d'étude des grottes de Montmaurin sur des sites sénégalais a donné des résultats significatifs : approvisionnement local en matière première avec une utilisation de galets ; traitement différentiel de la matière, changement dans le choix, orienté vers les roches siliceuses ; abandon du macro-outillage et diversification des matières, pour les étendre sur l'ensemble des sites Acheuléens du Sénégal et plus largement en Afrique de l'Ouest, afin d'établir une nouvelle séquence de référence en Afrique occidentale de l’Early Stone Age, jusqu'au Later Stone Age. / The huge karstic network of Montmaurin is located at the western end of the chain of the Petites Pyrenées, and contained several caves. There are only eight caves that have escaped the exploitation of quarrymen. Despite the dispersion of the collections, the lithic industry of the L. Meroc and R. Cammas' excavations in the Montmaurin caves benefited from an inventory and the study of the Acheulean and Mousterian collections.The techno-typological and petro-archaeological study conducted during this research shows the specificities inherent to the Montmaurin caves. The characteristics of what we propose to call "the Montmaurin complex" have a specificity in the Pyrenean foothills. This "complex" has a typological and technological unity. The lithological procession is composed of pebbles quartzite lydian quartz. that come from the tributaries of the Garonne and pre-Pyrenean flint. The acquisition territories of mineral resources are more or less vast, from a hundred meters to about 80 kilometers. We applied this method to Senegalese sites yielded significant results: local supply of raw material with a use of pebbles, a differential of the raw material, change in the choice, oriented towards siliceous rocks, abandonment of macro-tools and diversification. These results allow us to propose the application to Acheulean sites in Senegal and widely in West Africa, for establishing a new reference sequence in West Africa from Early Stone Age to Later Stone Age.
143

L’ichnologie préhistorique et les traces d’activités au sein des cavités ornées : les grottes de Fontanet (Ariège) et de Cussac (Dordogne). / Prehistoric ichnology and activity traces in the decorated caves : the caves of Fontanet (Ariège) and Cussac (Dordogne).

Ledoux, Lysianna 25 January 2019 (has links)
Vestiges fragiles et longtemps mésestimés, les empreintes constituent une source précieuse d’informations concernant la fréquentation d’un site. Actuellement largement étudiées en contexte de plein air, elles le sont beaucoup moins en grotte, contexte dans lequel leur étude a connu son apogée entre les années 1970 et le début des années 2000. Ces dernières années, l’intérêt des préhistoriens pour l’ichnologie en milieu souterrain s’est de nouveau manifesté et s’est concrétisé par la reprise de l’étude des empreintes dans plusieurs grottes ornées. Notre étude s’inscrit dans cette dynamique et vise à contribuer à la recherche autour des empreintes à partir du registre karstique et à participer au renouvèlement de la discipline en Préhistoire. Notre intérêt s’est porté sur les empreintes des grottes de Fontanet (Ariège) et de Cussac (Dordogne), d’abord du point de vue de leur formation et de leur conservation au cours du temps, puis de leur contribution à la compréhension de l’appréhension du monde souterrain par l’Homme au Paléolithique.À travers des observations, inventaires, mesures in situ et un travail ex situ grâce aux outils d’imagerie tridimensionnelle, nous avons mené une étude morphologique et morphométrique des empreintes fossiles. La singularité des empreintes de pied de Cussac nous a, en outre, amené à développer une approche expérimentale afin d’appréhender les différents facteurs ayant pu influencer leur morphologie au moment de leur formation et après celle-ci (taphonomie, port de chaussant, autre ?). Ces expérimentations ont mis en évidence un impact du substrat et de sa remobilisation sur la morphologie générale et les dimensions de l'empreinte, ainsi que la préservation de détails comme les orteils. La réalisation d'empreintes à l'aide de chaussants expérimentaux a conduit de plus à envisager l'utilisation de ce type de protection dans la grotte. Notre approche à la fois pluri et interdisciplinaire permet d’affirmer l’unicité des grottes de Fontanet et de Cussac d’un point de vue ichnologique, archéologique et géomorphologique. Tandis qu’à Cussac, la présence humaine semble avoir été limitée (aller/s et retour/s) et avoir répondu à un objectif précis (réalisation des gravures et dépôts humains ?), à Fontanet, la fréquentation semble s’être inscrite dans la durée et a impliqué plusieurs catégories d’individus (présence de juvéniles) et des activités variées.Des comportements souterrains similaires et qui se retrouvent durant l’ensemble du Paléolithique sont aussi mis en évidence (exploration globale des cavités, etc.). Ces travaux se présentent alors comme une contribution essentielle aux discussions relatives à la fonction de ces deux cavités. / Tracks, which are among the most fragile and underestimated archaeological remains, represent a valuable source of information on site frequentation. In the past few years, they were widely studied in open air contexts. However, their analysis in caves, a context in which their study reached its peak between the 1970s and the early 2000s, is much less common. Recently, interest towards ichnology in subterranean environments re-emerged among prehistorians, and the study of tracks in several decorated caves was resumed. Our study is part of this dynamic and aims to contribute to research on tracks from the karst register and to participate in the renewal of the discipline in Prehistory. We study the footprints of the caves of Fontanet (Ariège) and Cussac (Dordogne), focusing firstly on their formation and conservation over time, and secondly on their contribution to the understanding of the subterranean environment appropriation by human in the Palaeolithic.Through observations, inventories, in situ measurements and ex situ work based on three-dimensional imaging tools, we conducted a morphological and morphometric study of fossil tracks. In addition, we have developed an experimental approach to understand the various factors that may have influenced the morphology of footprints at the time of their formation and since their formation. This multidisciplinary and interdisciplinary approach makes it possible to affirm the uniqueness of the Fontanet and Cussac caves from an ichnological, archaeological and geomorphological point of view and at the same time reveals similar behaviours that can be found throughout the Paleolithic period. The profile of individuals who have frequented these two cavities gradually takes shape. We propose several hypotheses concerning their behaviour and activities in this confined and naturally constraining space and contribute to the discussions relating to the function of these two cavities.
144

Ecologia populacional e comportamento de peixes subterrâneos, Rhamdia sp. n. e Ancistrus sp. n., da área cárstica da Serra da Bodoquena, Mato Grosso do Sul (Siluriformes: Heptapteridae, Loricariidae) / Population ecology and behaviour of subterranean fishes, Rhamdia sp. n. e Ancistrus sp. n. from Serra da Bodoquena karstic area, Mato Grosso do Sul (Siluriformes: Heptapteridae, Loricariidae)

Borghezan, Rodrigo 12 March 2013 (has links)
O presente projeto estudou aspectos da ecologia populacional de duas novas espécies troglomórficas de Siluriformes dos gêneros Rhamdia e Ancistrus, sintópicas em um riacho subterrâneo da área cárstica da Serra da Bodoquena, Mato Grosso do Sul. Foram investigados os tamanhos e as densidades populacionais com base em censo visual e marcação e recaptura, as taxas de sobrevivência, a taxa de crescimento individual, a frequência de comprimento-padrão, de peso e de fator de condição, e os deslocamentos. Adicionalmente, foi estudado o comportamento de Rhamdia sp. n., com foco na ritmicidade locomotora e na reação à luz. Foram realizados seis eventos de coleta entre 2010 e 2011 para tomada de dados populacionais, além de prospecções por novas localidades com ocorrência dessas espécies. O tamanho populacional estimado para Rhamdia sp. n. foi de 391 indivíduos na Gruta das Fadas e 104, na Gruta Cinco de Ouros. Com base nos resultados de densidade, a população de Ancistrus parece ser menor do que a de Rhamdia sp. n., com tamanho populacional na ordem de 100 indivíduos. A densidade populacional média estimada através do censo visual para Rhamdia sp. n. foi de 0,09 ind/ m² na Gruta das Fadas e 0,1 ind./ m² na Gruta Cinco de Ouros, valores inferiores ao calculado com base nos resultados de marcação e recaptura, 0,76 ind./ m² e 1,48 ind./m², respectivamente. Em Ancistrus sp. n., a densidade populacional média foi de 0,018 ind/ m². Foi observado que Rhamdia sp. n. se concentra mais em poções, enquanto que Ancistrus sp. n., em corredeira. A pequena variação ao longo do ano nas densidades, no peso, e no fator de condição de ambas as espécies na Gruta das Fadas, indica maior estabilidade ambiental nessa caverna em comparação com a Gruta Cinco de Ouros. Em Rhamdia sp. n., indivíduos sem olhos externamente visíveis (anoftálmicos) apresentaram maior taxa de sobrevivência quando comparados com aqueles com olhos assimétricos ou dois olhos normais. O crescimento individual de Rhamdia sp. n. foi heterogêneo, sem relação com o tamanho do indivíduos e apresentou, pelo modelo de von Bertalanffy, comprimento máximo médio de 170 mm CP e constante de crescimento (K) de 0,241 A longevidade máxima média foi de aproximadamente 15 anos. Com a maior parte das recapturas ocorridas no mesmo setor da captura anterior, indivíduos de Rhamdia sp. n. apresentam filopatria, enquanto que Ancistrus sp. n. se deslocou mais, com somente um registro de recaptura no mesmo setor da captura anterior. Quanto ao comportamento de Rhamdia sp n., os exemplares apresentaram ritmicidade circadiana significante, com diferenças intra-específicas nos valores de potência espectral. No estudo de reação à luz, observou-se variação intra-específica no grau de fotofobia relacionado com a morfologia dos olhos. Prospecções realizadas em 24 cavernas do Assentamento Campina revelam que Rhamdia sp. n. ocorre até o momento somente nas cavernas Fadas, Cinco de Ouros, Manoel Cardoso e Dona Benedita, enquanto que ncistrus sp. n. somente na Gruta das Fadas. O mosaico de variações morfológicas observado em Rhamdia sp. n. e em Ancistrus sp. n., a forte ritmicidade circadiana da atividade locomotora e o elevado grau de fotofobia observado em Rhamdia sp. n., sugere que estas espécies estão em estágio inicial de fixação de caracteres troglomórficos, indicando um isolamento recente no hábitat subterrâneo / This project studied aspects of the population ecology of two troglomorphic Siluriformes of genera Rhamdia and Ancistrus, which are syntopics in a subterranean stream of Serra da Bodoquena karst area, Mato Grosso do Sul. The research comprised the investigation of the population sizes and densities, survival rates, individual growth rate, frequency of standard length, weight and condition factor, and displacements. Adicionally, the behavior of Rhamdia sp. n. was investigated with focus on locomotor rhythmicity and reaction to light. Six collections were made between 2010 and 2011 to gather population data, based on visual census and mark-recapture, as well as search for other localities to investigate the distribution range of these species. The population size estimated to Rhamdia sp. n. was 391 individuals in Fadas Cave and 104 individuals in the Cinco de Ouros Cave. The population densities of Ancistrus sp. n. suggests a lower population size compared to Rhamdia sp. n., possibly with less than 100 individuals in the studied area. The average population density estimated through visual census to Rhamdia sp. n. was 0.09 ind / m² in the Fadas Cave and 0.1 ind. / m² in the Cinco de Ouros Cave, lower than the results estimated by mark-recapture, 0. 76 ind. / m² and 1.48 ind. / m², for each cave, respectively. To Ancistrus sp. n., the average population density was 0.018 ind / m². The low variability throughout the year in population densities, weight, and in condition factor for both species in Fadas Cave, indicate and higher environmental stability in this cave compared to Cinco de Ouros Cave. In Rhamdia sp. n., individuals without externally visible eyes (anophthalmics) showed higher survival rate compared to those with asymmetric or two normal eyes. The individual growth of Rhamdia sp. n. was heterogeneous with no relation to individuals\' size and through the von Bertalanffy model estimate the maximum length (L ∞) of 170 mm and growth constant (K) of 0.241. The median maximum longevity was 15 years. With little movement between sectors, individuals of Rhamdia sp. n. exhibited philopatry, while Ancistrus sp. n. moved around, with only one individual recaptured in the same cave sector. In relation do behavior Rhamdia sp n. showed significant circadian rhythmicity, with intra-specific differences in the spectral power values. In the study of light reduction, the intra-specific variation was observed in the degree of photophobia related to eyes morphology. Surveys conducted in 24 caves in the Campina settlement revealed that Rhamdia sp. n. occurs in the Fadas, Cinco de Ouros, Manoel Cardoso and Dona Benedita caves, while Ancistrus sp. n. occurs only in the Fadas Cave. The mosaic of morphological variations observed in Rhamdia sp. n. and Ancistrus sp. n., the strong circadian locomotor activity and the high degree of photophobia observed in Rhamdia sp. n. suggests that these species are in early stages of setting troglomorphic characters, indicating a recent isolation in subterranean environment
145

O geossistema do Córrego do Couto, PETAR, Iporanga - SP: uma contribuição ao levantamento do patrimônio espeleológico

Martins, Carlos Eduardo 20 October 2014 (has links)
Made available in DSpace on 2016-04-27T18:15:45Z (GMT). No. of bitstreams: 1 Carlos Eduardo Martins.pdf: 12919368 bytes, checksum: dc12ff2b7d2dc395f9a2d8deb33ad004 (MD5) Previous issue date: 2014-10-20 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / This text deals with the importance of a karst spring. The Cachoeira do Córrego do Couto is one of the attractions of the Parque Estadual e Turístico do Alto Ribeira - PETAR, Iporanga - SP. The site is a resurgence of existing karst aquifer in a range between depressed carbonate rock saws higher impervious surfaces. The aquifer is composed of autologous and allogeneic systems water recharge, characterized for this reason as a mixed karst. As the object of study is a component of a landscape that remains dynamic relationships with society and also presents aspects of natural and human history, it is believed that the best approach for implementation of this work is the concept of geosystem. The concept is quite geosystem employed in studies of objects that have a natural origin, but are influenced by human activities. The results of the surveys carried out are a zoning map of the karst. In this map, the features are at the same time, resulting from and interact in the morphogenetic process responsible for landscape planning in the context of PETAR aims to provide recreation visitors for their aesthetic attributes / Este trabalho trata sobre a importância de uma fonte cárstica, a Cachoeira do Córrego do Couto que é um dos atrativos turísticos do Parque Estadual e Turístico do Alto Ribeira PETAR, Iporanga SP. O local é a ressurgência de um aquífero cárstico existente em uma faixa de rocha carbonática deprimida entre serras de superfícies impermeáveis mais elevadas. O aquífero mencionado é composto por sistemas de recarga alogênicos e autogênicos, caracterizando-se por este motivo como um carste misto. Como o objeto de estudo é um componente de uma paisagem que mantém relações históricas e bastante dinâmicas com a sociedade guardando aspectos da história natural e até mesmo humana regional, julgou-se que a melhor forma de abordagem para o desenvolvimento deste trabalho seria o conceito de Geossistema. O conceito de Geossistema é bastante empregado em estudos de objetos que tenham origem natural, mas que sejam influenciados pelas atividades humanas. O resultado dos levantamentos levados a efeito é um mapa de zoneamento do carste estudado no qual as feições são, ao mesmo tempo, resultantes do e interagem no processo morfogenético responsável pelo ordenamento da paisagem que no contexto do PETAR tem a finalidade de proporcionar a recreação dos visitantes por seus atributos estéticos
146

Apport de la taxonomie intégrative à la compréhension des mécanismes à l'origine de la biodiversité des spongiaires dans les grottes sous-marines / Integrative taxonomic contribution to the understanding of mechanisms at the origin of the biodiversity of sponges in submarine caves

Ruiz Pinzón, César Augusto 23 June 2017 (has links)
Les éponges Homoscleromorpha constituent l’une des grandes Classes des Porifera. Particulièrement bien distribuées dans les grottes sous-marines. Leur taxonomie et systématique sont particulièrement difficiles, à cause de l’absence fréquente de caractères diagnostiques. A partir d’une approche de taxonomie intégrative, couplant morphologie, cytologie et génétique, le premier objectif de cette thèse était d’améliorer la connaissance de la biodiversité des Homoscleromorpha. Les espèces nouvelles représentent 40% des éponges récoltées au cours de cette étude. Ce document présente 3 nouvelles espèces et 1 nouveau genre récemment publiés. L’ensemble des résultats acquis au cours de cette thèse appelle à une redéfinition des deux familles provocant un premier grand bouleversement de la Systématique de ce groupe.Un deuxième grand objectif de cette thèse était d’apporter des connaissances sur la diversité chimique et microbienne de ce groupe d’éponges. En étudiant un grand nombre de représentants nous avions l’ambition d’apporter des éléments de compréhension du succès écologique des Homoscleromorpha dans les grottes sous-marines. A l’aide d’approches metabolomiques et de metabarcoding, nous avons mis en évidence des patrons de diversité chimique et microbienne en fonction de différentes variables, traduisant pour certains un signal phylogénétique et dans d’autres une influence de l’environnement. Cette partie de la thèse était un pré-requis indispensable pour comprendre les capacités adaptatives des holobiontes Homoscleromorpha à travers l’expression de métabolites et/ou l’acquisition de microorganismes spécialisés, et leur évolution dans un environnement contraignant. / Homoscleromorpha sponges constitute one of the four Classes among Porifera. Their taxonomy and systematics are challenging due to the frequent absence of diagnostic characters. Particularly well distributed in cryptic habitats like submarine caves. Using an integrative approach based on morphology, cytology and genetics, the first objective of this thesis was to improve our knowledge on the biodiversity of Homoscleromorpha in submarine caves. New species represents 40% of the Homoscleromorpha collected. Here we present 3 new species and one genus recently published, 11 other new species being currently under description. Our results strongly support a redefinition of the two families of Homoscleromorpha. Our results represents a first grand overturn in the systematics of this group.A second objective of this thesis was to improve our knowledge on the chemical and microbial diversity of Homoscleromorpha but also its variability according to the environmental conditions. Our analysis provides preliminary data to address the question of the ecological success of Homoscleromorpha in submarine caves. Metabolomics and metabarcoding data defined patterns of chemical and microbial diversity according to different explicative variables like the taxonomy, the geographical origin or the ecology of the studied species. The patterns of diversity were supported by chemical and microbial markers and they explain a phylogenetic classification in few cases and a geographic origin in others. This study brings first insights into the understanding of the adaptive capacities of the Homoscleromorpha holobiont, through the expression of particular metabolites and/or microorganism.
147

Simulation Modeling of Karst Aquifer Conduit Evolution and Relations to Climate

Broome, John D 01 December 2008 (has links)
ABSTRACT Karst regions of the world that receive relatively similar amounts of precipitation display a wide variety of landscapes. It has been suggested (Groves and Meiman, 2005) that climates exhibiting larger discrete storm events have more dissolving power and consequently higher rates of conduit growth than climates with more uniform precipitation distributions. To study this concept, a computer program “Cave Growth” was developed that modeled the growth of a cross-section of a cave passage under dynamic flow and chemical conditions. A series of 46 simulation datasets were created to represent different climatic conditions. These simulations had the same total annual discharge, but demonstrated a range of flow distributions quantified by use of a gamma distribution index, along with two special theoretical cases. After simulating a year of conduit growth for each of the various flow distributions in a series of model runs, and repeating these sets of simulations for three different passage cross-section geometries, it was evident that the annual temporal distribution of flow did indeed impact the amount of cave growth. However, an increase in the “storminess” of the climate did not simply equate to more dissolution and thus conduit growth. Rather, the quantity and duration of surface contact between water and the conduit walls combined with dissolution rates to affect the total growth. The amount of wetted perimeter (contact between fluid and passage floor/walls) generated by specific conduit to capacity were shown to be very effective at growing the cave. Above this level, the dissolving power of additional water was essentially wasted. This investigation suggests that the maximum amount of passage flow levels depended upon the shape of the passage. Flow conditions that filled the growth occurs under flow conditions that result in the most wetted perimeter for the longest period of time at the highest dissolution rate.
148

Application and Refinement of the Karst Disturbance Index in West Central, Florida

North, Leslie A. 26 April 2007 (has links)
A hierarchical and standardized environmental disturbance index, specifically designed for karst landscapes, was created by van Beynen and Townsend (2005). To assess the applicability of the index and provide recommendations for its refinement, the index was applied in four west-central Florida counties and interviews were conducted with local and state officials, community planners, and land resource managers. The karst disturbance index consists of 30 indicators contained within five broad categories: geomorphology, hydrology, atmosphere, biota, and culture. Data was readily available for most environmental indicators used to construct the index. Overall, levels of disturbance vary between the counties due to the level of urbanization, with the highly populated Hillsborough and Pinellas Counties having higher degrees of disturbance than less developed Pasco and Hernando Counties. While this result may seem obvious, the measure of disturbance using many indicators provides benchmarks of levels of disturbance that can be reassessed with time and highlights those aspects of the environment most in need of attention. Several minor issues arose during the testing: the need for broader indicator descriptions that encompass a variety of scenarios, a new water quality indicator, obsolete sinkhole data, and a lack of data for biota indicators. The lack of data for certain indicators suggests where future research efforts can be directed.
149

Quasi 3-Dimensional Electrical Resistivity Mapping of Air-filled Karst Conduits and Policy Implications

Mccrackin, Charles W. 01 January 2012 (has links)
This study assesses the capability and practical applications of quasi 3-Dimensional (3D) electrical resistivity surveying (ER) for mapping air-filled karst conduits. Vadose zone caves within the Brooksville Ridge of West Central Florida are relatively similar in architecture, with N-S elongation, and do not consist of an interconnected network of conduits. A high resolution quasi-3D ER survey was performed over two mapped cave systems on the Brooksville Ridge. The resultant survey verified the general effectiveness of quasi-3D ER in locating the two known near-surface cave features. Several other locations in the survey show similar or stronger resistivity anomalies trending in a N-S direction; these are interpreted to represent previously unknown voids. The quality of inversion results were tested by comparing results against the known void locations and by computing cross-over errors from surveys conducted at the same point with different orientations. Our results show that 3D inversions of multiple adjacent parallel profiles produces higher quality results (lower cross-over errors, better fit to cave locations) than 2D inversions. The data indicate that no single value of resistivity can be used as a reliable indicator of the presence of a void, presumably due to variable void size and the complexity in resistivities in the host rock. With sinkholes continuing to be of concern to residential and urban development in West Central Florida, the results of this research show the necessity of applying geophysical techniques in order to reduce the potential hazards posed by karst terrain.
150

Μελέτη σπηλαιοθεμάτων από το σπήλαιο Αγίου Γεωργίου του νομού Κιλκίς : διερεύνηση των παλαιοκλιματικών περιβαλλοντικών συνθηκών με χρήση των σταθερών ισότοπων C και Ο

Αντωνέλου, Ασπασία 27 January 2015 (has links)
Η παρούσα εργασία έχει σαν σκοπό την μελέτη των σπηλαιοθεμάτων από το σπήλαιο του Αγίου Γεωργίου στην περιοχή του Κιλκίς. Με αυτή την μελέτη διαπιστώθηκαν οι μεταβολές των περιβαλλοντικών συνθηκών με το πέρασμα των ετών, οι οποίες αποτυπώνονται στα στρώματα δημιουργίας των σπηλαιοθεμάτων. Η αποπεράτωση της εργασίας έγινε σε στάδια. Αρχικά υπήρξε υπαίθρια εργασία που χωρίστηκε σε δύο φάσεις. Στην πρώτη φάση έγινε συλλογή υδάτων της ευρύτερης περιοχής για περαιτέρω αξιολόγηση τους, και κατά την δεύτερη πραγματοποιήθηκε δειγματοληψία των ανθρακικών(σταλακτιτών) μέσα από το σπήλαιο. Στο επόμενο στάδιο πραγματοποιήθηκαν εργαστηριακές έρευνες. Έτσι από τα δείγματα που συλλέχθηκαν από την περιοχή του αμέσου ενδιαφέροντος φτιάχτηκαν λεπτές τομές, που μελετήθηκαν μικροσκοπικά. Για να γίνει ακριβής προσδιορισμός των ορυκτών πραγματοποιήθηκε ορυκτολογική ανάλυση με την μέθοδο της περιθλασιμετρίας, και ακολούθησαν μια σειρά από ορυκτοχημικές αναλύσεις. Παράλληλα με αυτές τις εργασίες πραγματοποιήθηκαν αναλύσεις υδάτων τόσο την χημική όσο και για την ισοτοπική σύσταση τους. Επιπλέον με δειγματοληψία στα ανθρακικά(σταλακτιτών) με κατάλληλη μέθοδο, προσδιορίστηκε και η ισοτοπική σύσταση των ανθρακικών(σταλακτιτών) με σκοπό την αποτύπωση των μεταβολών του κλίματος. / -

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