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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.
21

High-resolution lake-based magnetic mapping and modelling of basement structures, with examples from Küçükçekmece Lagoon, Turkey and Charity Shoal, Lake Ontario

Suttak, Philip A. 10 1900 (has links)
<p>Magnetic surveys are one of the principal geophysical methods employed to map the structure of basement rocks deeply buried below cover strata. In resource studies, aeromagnetic surveys are commonly acquired at regional scales (100-1000’s km2) while very few studies have attempted to resolve basement structures at site-scale (<10 >km2). In this study, high-resolution lake-based magnetic survey methods were evaluated for mapping of deeply-buried basement faults (Küçükçekmece Lagoon, Turkey; 6 km2) and a suspected meteorite impact crater (Charity Shoal, Lake Ontario; 9 km2). Total magnetic intensity (TMI) surveys were acquired using a single Overhauser magnetometer with 50-150 m line spacing. Interpretation of the magnetic data was aided by forward modelling of TMI data and depth to basement estimates using Euler and analytic signal methods. Total magnetic intensity (TMI) maps of Küçükçekmece Lagoon identify several north-northwest trending (340-350°) magnetic lineaments that are aligned with strike-slip faults mapped from offshore seismic data. The pattern of magnetic anomalies in the lagoon is consistent with extensional normal faulting of bedrock and lake sediments. Magnetic results from Charity Shoal reveal a large (>1400 nT) parabolic-shaped magnetic anomaly centered over the crater basin and an annular magnetic high (40-50 nT) corresponding with the basin rim. Modelling results exclude the origin of the CSS as a shallow glacial erosional or karst sinkhole feature and are most consistent with a pre-Paleozoic meteorite impact in the Precambrian basement.</p> / Master of Science (MSc)
22

Reconstitution paléogéographique et prospection archéologique en zone littorale par approches géophysiques multi-méthodes et multi-échelles / Paleo-geographical reconstitution and archaeological survey in coastal area by multi-method and multi-scale geophysical approaches

Bruniaux, Guillaume 07 December 2017 (has links)
L’étude archéologique d’un site est réalisée sur la base d’une fouille, qui est une étude précise sur une ouverture restreinte. En amont de cette opération, la prospection géophysique offre la possibilité de localiser une zone susceptible d’apporter des informations majeures par une cartographie détaillée du site. Ces travaux de thèse se focalisent sur un protocole original de prospection magnétique pour détecter des structures pluri-métriques à pluri-décimétriques et une démarche méthodologique pour estimer la conservation d’un niveau d’occupation archéologique. Ces développements ont été réalisés pour apporter un maximum d’information sur l’occupation anthropique et cibler une zone de fouille suivant la problématique archéologique associée au site. Dans les zones littorales et suivant la période chronologique considérée, l’environnement associé à une occupation était différent. La modification relativement rapide des environnements côtiers résulte de la remontée du niveau marin depuis la fin du dernier maximum glaciaire. Dans le cadre d'une étude paléoenvironnementale associée à un site, l’objectif de la prospection géophysique est similaire à celle effectuée pour une fouille : localiser une zone d’implantation des carottages paléoenvironnementaux. La démarche méthodologique développée dans ces travaux est basée sur une approche paléogéographique de l’environnement à partir de prospections géophysiques multi-méthodes et multi-échelles. Des prospections électromagnétiques (Slingram), des sections électriques et des diagraphies électriques (direct-push) apportent une représentation cartographique et stratigraphique des contrastes géophysiques de la subsurface. Deux zones d’étude ont été sélectionnées pour tester et mettre en place ces démarches méthodologiques, le site néolithique du Pontet (Charente-Maritime) et les ports antiques de Narbonne. Ces deux sites sont dans des contextes archéologiques, géographiques et géologiques différents. / Archaeological study of a site is based on an excavation which is a comprehensive study on a restricted gap. Before excavation, geophysical survey supplies the possibility to locate an area likely to provide details by detailed mapping of the site. This PhD work focus on an original magnetic survey protocol to detect pluri-metric and pluri-decimetric structures and a methodological approach to estimate the conservation of an archaeological level occupation. These developments have provided maximum information on anthropogenic settlement and to target excavation zone according to the archaeological problem of the site. In coastal zones and according to the considered chronological period, the environment of the settlement was different. The relatively rapid change in coastal environments results from the rise of sea level since the end of the last glacial maximum. As part of a paleoenvironmental study of a site, the objective of geophysical survey is similar to that for excavation : locating an area to paleoenvironmental coring. The methodological approach developed in this work is based on a paleogeographic approach to the site environment using multi-method and multi-scale geophysical surveys. Electromagnetic survey (Slingram), electrical tomography and direct-push electrical resistivity logging provide a cartographic and stratigraphic representation of the geophysical contrasts of the subsurface. Two study areas were selected to test and implement these methodological approaches, the Neolithic site of Le Pontet (Charente-Maritime) and the ancient harbours of Narbonne. These two sites are in different archaeological, geographical and geological contexts.
23

Remnant echoes of the past : Archaeological geophysical prospection in Sweden

Viberg, Andreas January 2012 (has links)
The aim of this thesis has been to investigate the benefits, pitfalls and possibilities of using geophysical methods in archaeological projects. This is exemplified by surveys carried out at archaeological sites in different geographical and chronological contexts. The thesis also aims at investigating the cause for the under-use of the methods in Swedish archaeology by looking at previously conducted surveys. The methods used during these surveys have been Ground-penetrating radar (GPR), magnetometer, slingram and a kappameter. The surveys in the mountain tundra region of Lapland show that magnetic susceptibility surveys is a valuable aid in discovering heaps of fire-cracked stones and when combined with magnetometry, also hearths. GPR and magnetometer surveys within the Migration Period ringfort Sandbyborg provided the spatial layout of the fort and indicated, along with results from recent excavations and metal detections, many similarities with the ringfort Eketorp II. The non-magnetic character of the sedimentary bedrock on Öland and Gotland is suitable for magnetometer surveys and the method is also highly appropriate for the detection of the remains of high-temperature crafts. GPR surveys at St. Mary’s Dominican convent in Sigtuna produced the spatial layout of the central cloister area. The investigations also show that the geology, pedology, land use and the character of commonly occurring prehistoric remains in Sweden, in certain circumstances and in certain areas, have restricted the possibility of successfully carrying out geophysical surveys. Care must therefore be taken to choose the right instrument for the survey and to tailor the sampling density of each geophysical survey, according to the character and size of the expected archaeological remains, in order to maximize their information return. To increase the use of geophysical methods in Sweden the educational opportunities, both for surveyors and professional archaeologists, need to improve. / <p>At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 2: Submitted. Paper 3: Manuscript.</p>
24

Landscape archaeogeophysics : a study of magnetometer surveys from Etowah (9BW1), the George C. Davis site (41CE19), and the Hill Farm site (41BW169)

Walker, Chester Phil 08 November 2011 (has links)
Archaeogeophysics, the use of eophysical mapping techniques to recover archaeological information, is being used with increasing success in North America. Archaeologists can often use geophysics as a tool for collecting data suitable for direct archaeological interpretation (Kvamme 2003). In some cases, geophysics can be used to map entire archaeological landscapes providing an image of the site that is not easily achievable through the use of traditional archaeological excavations. This dissertation uses archaeogeophysical data from three prehistoric sites to gain insights into their layout and community organization as well as explore the possibilities and potentials of using broad scale geophysical surveys in North American archaeological research. / text
25

Occupation de la plaine de Persépolis au Ier millénaire av. J.-C. (Fars central, Iran) / The Persepolis plain settlement during the first millenium BC (Central Fars, Iran)

Gondet, Sébastien 02 April 2011 (has links)
Fondée par Darius Ier (522-486 av. J.-C.), Persépolis constituait une des résidences royales temporaires des souverains de l’Empire achéménide (550-330 av. J.-C.). Elle était également un centre administratif et économique, capitale d’une vaste province, la Perse, située au cœur de l’Empire. L’organisation de Persépolis reste largement méconnue de même que celle du vaste territoire, la plaine environnante, qu’elle contrôlait.Notre étude vise à mieux comprendre d’une part l’occupation du site de Persépolis qui va de la terrasse monumentale à la nécropole royale à 6 km au nord, d’autre part la mise en valeur de la plaine, en replaçant la période achéménide dans le contexte plus large du Ier millénaire av. J.-C. Dans un premier temps, l’étude prend en compte les dynamiques environnementales de la région. Les recherches sont fondées sur les méthodes de prospections archéologiques (reconnaissances à vue et méthodes géophysiques). Elle aboutit à une reconstitution d’une ville répartie en plusieurs blocs de fonctions différentes (habitats ordinaires, zones artisanales, résidences de l’élite et bâtiments de prestige) séparés les uns des autres par de vastes espaces non-bâtis mais probablement aménagés.Pour la plaine (100 km par 30 km), la prospection des sites achéménides a dû prendre en compte les graves destructions liées à la modernisation (agriculture, urbanisation, voies de communication) et s’est concentrée sur quelques sites préservés et des zones de piedmonts sélectionnées. Ces recherches ont montré une occupation très distendue essentiellement localisée dans la partie nord de la plaine et incluant la zone de Persépolis. La partie sud de la plaine était beaucoup moins exploitée. Cependant cette reconstitution doit tenir compte de la réduction sévère du potentiel archéologique, tout particulièrement dans le cadre de l’étude de l’occupation à la période achéménide, lorsque l’exploitation du sol reposait sur des installations rurales de dimensions modestes. / Founded by Darius I (522-486 BC), Persepolis represented one of the seats of the kings of the Achaemenid Empire (550-330 BC). Moreover, the site served as an administrative and economic centre and acted as capital for the vast province, named Persia, situated in the heart of the Empire. The spatial character of both the royal site as well as the wider hinterland it controlled, the vast surrounding plain, are however largely unknown.The study aims at providing better insight in both the occupation of the site of Persepolis, stretching from the monumental terrace to the royal necropolis 6 km farther north, along with that of the supporting plain. It therefore frames and evaluates the Achaemenid period within the context of the first millennium BC. At the outset, the study integrates the environmental dynamics of the region. The research was based on the methods of archaeological survey (field survey and geophysical methods) and allowed to reconstruct a ‘city’ composed of different functional zones (common housing, industrial quarters, elite residences, and royal monuments) separated from one another by large areas, presumably unbuilt though exploited.For the plain (100 by 30 km), the survey of Achaemenid sites was biased by the important destructions by recent development (industrialised agriculture, urbanism, transport and communication). Research has therefore been focussed on a number of preserved sites on the one hand and on selected piedmont areas on the other. These surveys brought to light a scattered occupation, predominantly situated in the northern part of the plain, also encompassing the Persepolis zone, while the southern region of the plain was less occupied. Nonetheless, this reconstruction should take into account the important reduction of archaeological potential, particularly in the case of a study focussing on the Achaemenid occupation since settlement in the wider Persepolis area was first and foremost of rural natural and of rather modest size.
26

Vesnické osídlení v zázemí vrcholně a pozdně středověké Prahy. Sídelně-historický vývoj a zemědělství v příměstských oblastech / Rural settlements in the hinterland of Prague in high and late middle ages. Settlement and agriculture development in suburban regions

Beránek, Michal January 2013 (has links)
Master's thesis deals with the micro-region Klánovice's forest and its surroundings on the eastern edge of the City Prague. This area has not been given comprehensive attention yet. The findings are based on a critical review of the humble written and archaeological sources relating to the concerned area. In addition, was made, analysis of archaeological excavation, which was carried out on the deserted village Hol and also geophysical survey from the same site. Based on the lessons learned to better classify and discuss the role of this area in the hinterland of high medieval Prague. Keywords: deserted village, Klánovice forest, Hol, geophysical survey, ceramics, agricultural margins land, high middle ages
27

The O.C. Voss Site: reassessing what we know about the Fort Ancient occupation of the central Scioto drainage and its tributaries

Brady-Rawlins, Kathleen L. 07 June 2007 (has links)
No description available.
28

Comparaison de signaux (géophysique, LiDAR) utilisés dans l'étude des dynamiques anthropiques et naturelles / Comparison of signals (geophysics, LiDAR) used in the study of natural and anthropogenic dynamics

Laplaige, Clément 16 February 2012 (has links)
La caractérisation de la réalité matérielle du paysage impose d’une part de reconnaitre avec précision le cadre physique et d’autre part de saisir les interrelations entre les hommes et l’environnement, conditions indispensables à l’appréciation des origines du modelé du paysage. La compréhension des paysages passés se fonde en partie sur l’analyse de différentes sources documentaires qui permettent ensemble de caractériser bon nombre des évolutions paysagères intervenues notamment depuis l’époque moderne. Toutefois, les aménagements plus anciens ne sont ni localisés ni représentés sur des cartes. Leurs traces sont alors décelées dans le paysage actuel de manière efficace grâce notamment à la mise en oeuvre conjointe de diverses méthodes de détection : la photographie aérienne, enregistrant des variations topographiques ou colorimétriques à la surface du sol et le système LiDAR (Light Detection And Ranging), mesurant les variations microtopographiques à l’aide d’un laser. L’étude d’autres paramètres, imperceptibles à nos sens, permettent également d’appréhender les traces des paysages passés. Les méthodes géophysiques détectent la présence de vestiges ou de structures enfouies qu’aucun indice ne signale en surface grâce à la mesure des propriétés physiques du sol. Il est largement admis que les méthodes de prospection sont susceptibles de fournir des données archéologiques quant à l’occupation du sol et/ou l’exploitation du territoire. A ce titre, elles ont été appliquées depuis plusieurs années sur le site de l’agglomération antique d’Epomanduodurum (Mandeure-Mathay, Doubs) dans le nord Franche-Comté. Cette ville est considérée, par sa taille, son équipement urbain et sa parure monumentale comme la seconde de Séquanie derrière la capitale de cité Vesontio (Besançon, Doubs). Ce travail de recherche se propose donc de comparer, à différentes échelles spatiales, l’apport respectif de plusieurs méthodes de prospection à l’étude de dynamiques naturelles et anthropiques dans un espace géographique de 80 km², centré sur la ville antique, associant un tronçon de plaine alluviale du Doubs aux plateaux calcaires environnants. Durant cette étude, il a été possible, entre autre, de développer des outils aidant à la détection des structures archéologiques et géologiques. Les résultats ont aussi permis de redéfinir en partie la topographie de l’agglomération antique. / The characterization of the material reality of the landscape requires to accurately identify the physical geography and to capture the interrelationships between humans and their environment. These conditions are essential to the estimation of the origins of the landscape shaping. The analysis of documentary sources offers the opportunity to determine the organization of former landscapes and to characterize a large part of their evolutions since the Modern period. However, older land settlements are not localised or symbolised on maps. Their signs are efficiently detected in present landscape through the joint implementation of various detection methods: aerial photography, recording topographic or colorimetric variations on the soil surface, and the LiDAR (Light Detection And Ranging) system, measuring micro-topographic variations using a laser beam. Other methods can be used to identify the elements conserved in present landscape and reflect their past uses. The measure of physical properties of soils by the geophysical methods can detected the presence of archaeological remains or structures buried while nothing is perceptible to the soil surface. It is widely supported that survey methods can provide archaeological data of the land use and / or the exploitation of the territory. Thus, they have been applied since several at the site of the ancient city of Epomanduodurum (Mandeure-Mathay, Doubs) in the north of the Franche-Comte. This city is considered by its size, urban equipment and monuments as the second behind de civitas capital of Sequani, Vesontio (Besancon). This research intends to compare, at different spatial scales, the contribution of several prospecting methods for the study of natural and anthropogenic dynamics in an area of 80 km². The study area is centred on the ancient city and combines a section of the alluvial plain of the Doubs river and the surrounding calcareous plateaus. In this study, it was possible, among other things, to develop tools for the detection of archaeological
29

Αποτύπωση υποθαλάσσιων πολιτιστικών στοιχείων και βιολογικών πόρων στην παράκτια ζώνη της νήσου Λέρου / Marine geophysical survey for cultural and habitat mapping in the coastal zone of Leros island, Aegean sea, Greece

Κάτσου, Ευγενία 11 July 2013 (has links)
Η παρούσα μεταπτυχιακή διατριβή επικεντρώνεται στην μελέτη της παράκτιας ζώνης της νήσου Λέρου στο Νοτιοανατολικό Αιγαίο, παρουσιάζοντας τα αποτελέσματα της ερμηνείας των γεωφυσικών στοιχείων που συλλέχθηκαν από το Εργαστήριο Θαλάσσιας Γεωλογίας και Φυσικής Ωκεανογραφίας (Ε.ΘΑ.ΓΕ.Φ.Ω.) τον Ιούνιο του 2011. Η έρευνα φιλοδοξεί να συνεισφέρει στην ανάδειξη της υποθαλάσσιας πολιτιστικής και φυσικής κληρονομιάς του νησιού, καθώς η συλλογή, επεξεργασία και ερμηνεία του συνόλου των δεδομένων επέτρεψε την αναγνώριση και την λεπτομερή χαρτογράφηση υποθαλάσσιων στόχων μεγάλης ιστορικής και περιβαλλοντικής σημασίας. Ως εκ τούτου, η διατριβή κινείται σε δύο κατευθύνσεις. Η πρώτη κατεύθυνση αφορά στον εντοπισμό στόχων πιθανής ιστορικής σπουδαιότητας που εντοπίστηκαν στην επιφάνεια του πυθμένα ενώ η δεύτερη κατεύθυνση αφορά στον εντοπισμό και την αποτύπωση βιογενών σχηματισμών και συγκεκριμένα λειμώνων P. Oceanica και ασβεστιτικών ροδοφυκών (corallegene formations). Οι θαλάσσιες έρευνες πραγματοποιήθηκαν σε δύο διακριτά στάδια, στην συστηματική αποτύπωση του πυθμένα με ηχοβολιστή πλευρικής σάρωσης (EG&G 272 TD) και την οπτική επιβεβαίωση των αποτελεσμάτων της ηχοβολιστικής αποτύπωσης με σύστημα συρόμενης υποβρύχιας κάμερας. Η ανάλυση και επεξεργασία των ηχογραφιών οδήγησε στον εντοπισμό ναυαγίων που συνδέονται με τη Μάχη της Λέρου (9-10/1943), ένα από τα σημαντικότερα πολεμικά γεγονότα που έλαβαν χώρα κατά τη διάρκεια του Δευτέρου Παγκοσμίου πολέμου, στην ανατολική Μεσόγειο και τα οποία αποτελούν πολύτιμα ιστορικά στοιχεία σε παγκόσμια κλίμακα, μεταξύ των οποίων το βυθισμένο ελληνικό αντιτορπιλικό Βασίλισσα ‘Ολγα (D15). Στο πλαίσιο της δεύτερης κατεύθυνσης εντοπίστηκαν και χαρτογραφήθηκαν οι λειμώνες P. Oceanica και οι σχηματισμοί των ασβεστιτικών ροδοφυκών σχεδόν ανά όρμο περιμετρικά της νήσου. Η σχεδίαση των αντιστοίχων υποθαλάσσιων θεματικών χαρτών της παράκτιας ζώνης της Λέρου αναμένεται να αποτελέσουν ένα σημαντικό εργαλείο στην προστασία και στην ανάδειξη της σημαντικής υποθαλάσσιας ιστορικής και φυσικής κληρονομιάς του νησιού / The present study describes the submarine geophysical survey which was carried out in Leros Island, Aegean Sea and presents the results of the geophysical data analysis. The data were collected by the Laboratory of Marine Geology & Physical Oceanography, department of Geology, University of Patras during the period 11-17 June 2011. The research aims to contribute to the enhancement of underwater cultural and natural heritage of the island, as the collection, processing and interpretation of all of the data has allowed the identification of underwater targets of great historic and environmental importance. Geophysical survey in Leros Island, using a side scan sonar (EG&G 272 TD), coupled with ground-truthing by deploying a Towing Camera System of historic shipwrecks from World War II and of the major seabed habitats, namely Posidonia oceanica and coralligène formations. The survey revealed a great number of shipwrecks associated with the Battle of Leros (9-10/1943), one of the most important military events that took place during the World War II, in the Eastern Mediterranean which are considered as valuable historic data on a global scale, including the sunken Greek destroyer Queen Olga (D15). The design of the thematic maps of the coastal zone of Leros is expected to become an important tool in both protecting and promoting the significant underwater cultural and natural heritage of the island.

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