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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.
11

Geocronologia U-Pb em Zircão Detrítico aplicada ao estudo de proveniência de metassedimentos do Complexo Metamórfico Porongos – Região de Santana da Boa Vista, RS

Gruber, Leonardo January 2010 (has links)
Estudos de proveniência em zircões detríticos através do método U-Th-Pb (LA-ICP-MS) dos metassedimentos do Complexo Metamórfico Porongos determinaram a existência de duas áreas-fontes principais de onde derivaram idades paleoproterozóicas e mesoproterozóicas para os xistos Arroio Areião, Cerro Cambará e quartzo milonitos associados. Foram obtidas idades entre 967 ± 15 Ma e 2454 ±26 Ma para a seqüência Arroio Areião, entre 894 ± 30 Ma e 2783 ± 18 Ma para a seqüência Cerro Cambará, e idades entre 1621 ± 16 Ma e 3185 ± 117 Ma para os quartzo milonitos associados. A área fonte com idades paleoproterozóicas pode ser correlacionada ás rochas do Complexo Encantadas, que faz parte do embasamento das unidades supracrustrais. As áreas-fontes para os zircões mesoproterozóicos (entre 967 e 1621 Ma) não foram ainda reconhecidas no Cinturão Dom Feliciano. Estes zircões podem ser derivados de associações de rocha pertencentes aos cinturões mesoproterozóicos (orogêneses Elzeverian e Greenville), associados ao sistema geodinâmico que incluí os crátons Amazonas, Kalahari, Congo – São Francisco e Laurencia e cinturões associados. O ambiente geotectônico de formação da paleobacia Porongos é compatível com a margem passiva, onde se estabeleceu um arco magmático. Este trabalho demonstra que do ponto de vista isotópico e estratigráfico, não existem diferenças significativas de idades detríticas entre as seqüências metassedimentares que afloram nos flancos da Antiforme de Santana da Boa Vista. / Provenance studies based upon detritic zircon grain U-Th-Pb methodology (LA-ICP-MS) from metasediments of Porongos Metamorphic Complex have determined the existence of two principal source-areas with paleoproterozoic and mesoproterozoic ages to the schists of Arroio Areião, Cerro Cambará and associated quartz mylonites. Where obtained ages between 967 ± 15 Ma and 2454 ±26 Ma to the Arroio Areião sequence, between 894 ± 30 Ma and 2783 ± 18 Ma to Cerro Cambará sequence, and 1621 ± 16 Ma e 3185 ± 117 Ma to the associated quartz mylonites. The source-area with paleoproterozoic ages can be related to the Encantadas Complex rocks, which is basement of the supracrustal sequences. The source-areas to the mesoproterozoic zircons (between 967 and 1621 Ma) are not recognized in the Dom Feliciano Belt. These zircons can be related to mesoproterozoic petrotectonic associations (Greenville and Elzeverian orogens) associated to the geodynamic system that includes the Amazon, Kalahari, Congo – São Francisco and Laurentia cratons, and associated belts. The tectonic environment of Porongos paleobasin it’s compatible with a passive margin, after where established a magmatic arc environment. This work shows that from isotopic and stratigraphyc point of view there is no significantly differences between the metasedimentary sequences cropping out in both Santana da Boa Vista antiform flanks.
12

Geocronologia U-Pb em Zircão Detrítico aplicada ao estudo de proveniência de metassedimentos do Complexo Metamórfico Porongos – Região de Santana da Boa Vista, RS

Gruber, Leonardo January 2010 (has links)
Estudos de proveniência em zircões detríticos através do método U-Th-Pb (LA-ICP-MS) dos metassedimentos do Complexo Metamórfico Porongos determinaram a existência de duas áreas-fontes principais de onde derivaram idades paleoproterozóicas e mesoproterozóicas para os xistos Arroio Areião, Cerro Cambará e quartzo milonitos associados. Foram obtidas idades entre 967 ± 15 Ma e 2454 ±26 Ma para a seqüência Arroio Areião, entre 894 ± 30 Ma e 2783 ± 18 Ma para a seqüência Cerro Cambará, e idades entre 1621 ± 16 Ma e 3185 ± 117 Ma para os quartzo milonitos associados. A área fonte com idades paleoproterozóicas pode ser correlacionada ás rochas do Complexo Encantadas, que faz parte do embasamento das unidades supracrustrais. As áreas-fontes para os zircões mesoproterozóicos (entre 967 e 1621 Ma) não foram ainda reconhecidas no Cinturão Dom Feliciano. Estes zircões podem ser derivados de associações de rocha pertencentes aos cinturões mesoproterozóicos (orogêneses Elzeverian e Greenville), associados ao sistema geodinâmico que incluí os crátons Amazonas, Kalahari, Congo – São Francisco e Laurencia e cinturões associados. O ambiente geotectônico de formação da paleobacia Porongos é compatível com a margem passiva, onde se estabeleceu um arco magmático. Este trabalho demonstra que do ponto de vista isotópico e estratigráfico, não existem diferenças significativas de idades detríticas entre as seqüências metassedimentares que afloram nos flancos da Antiforme de Santana da Boa Vista. / Provenance studies based upon detritic zircon grain U-Th-Pb methodology (LA-ICP-MS) from metasediments of Porongos Metamorphic Complex have determined the existence of two principal source-areas with paleoproterozoic and mesoproterozoic ages to the schists of Arroio Areião, Cerro Cambará and associated quartz mylonites. Where obtained ages between 967 ± 15 Ma and 2454 ±26 Ma to the Arroio Areião sequence, between 894 ± 30 Ma and 2783 ± 18 Ma to Cerro Cambará sequence, and 1621 ± 16 Ma e 3185 ± 117 Ma to the associated quartz mylonites. The source-area with paleoproterozoic ages can be related to the Encantadas Complex rocks, which is basement of the supracrustal sequences. The source-areas to the mesoproterozoic zircons (between 967 and 1621 Ma) are not recognized in the Dom Feliciano Belt. These zircons can be related to mesoproterozoic petrotectonic associations (Greenville and Elzeverian orogens) associated to the geodynamic system that includes the Amazon, Kalahari, Congo – São Francisco and Laurentia cratons, and associated belts. The tectonic environment of Porongos paleobasin it’s compatible with a passive margin, after where established a magmatic arc environment. This work shows that from isotopic and stratigraphyc point of view there is no significantly differences between the metasedimentary sequences cropping out in both Santana da Boa Vista antiform flanks.
13

Určení geologické provenience katodoluminiscenční spektroskopií apatitů a karbonátů / Determination of geological provenance by cathodoluminescence spectroscopy of apatites and carbonates

Pánik, Róbert January 2015 (has links)
This work presents new method for determination of geological provenance based on the statistical analysis of cathodoluminescence spectra of marbles and carbonate rocks from various localities in the Bohemian Massif. Analysis is based on the combination of data from seven different measures of spectral similarity and provides results that are more robust than those obtained by approach based only on a single measure of similarity. These results may be further improved by employing meta-analysis that evaluates behaviour of spectra during the individual steps of analysis. Analysis was performed on the original cathodoluminescence spectra, as well as on the residual spectra in which relative variability was amplified by the subtraction of Gaussian trend present in all spectra of carbonates. By combining results from analysis and meta-analysis of both original and residual spectra it was possible to almost unambiguously determine provenance of samples from all studied localities. Agglomerative hierarchical clustering was employed as a supplementary method for classification of spectra. Out of 72 different methods for clustering, one was selected for both original and residual data based on the number of correctly classified spectra. Second part of this work presents analysis of cathodoluminescence...
14

Prehistoric Rockshelters of Pennsylvania: Revitalizing Behavioral Interpretation from Archaeological Spatial Data

Burns, Jonathan Allen January 2009 (has links)
The size of archaeological data collection units and provenience controls affect data resolution, types of analyses, and the interpretations that archaeologists draw from the spatial patterning of material evidence. This research examines the use of fine-grained data collection units and the analyses that they support in the study of two Pennsylvania rockshelters to: 1) provide a better understanding of rockshelter use and the importance of rockshelters in Pennsylvania and Middle Atlantic region prehistory and, 2) reveal the impact that archaeological units can have on the reconstruction and interpretation of human behaviors in general. Insights from behavioral theory, ethnoarchaeology and previous archaeological research influenced the units and methods employed in the excavation of the Mykut and Camelback rockshelters. This analysis reveals the range of behaviors that can be reconstructed from these data, which can then be compared and contrasted with interpretations of other rockshelters and site contexts in the region. / Anthropology
15

Chemická variabilita granátů z Českého středohoří a charakterizace jejich minerálních inkluzí / Chemical variability of garnets from the České středohoří Mountains and characterization of their mineral inclusions

Píšová, Barbora January 2020 (has links)
The samples of garnets used in this study come from clastic sediments from the drillcores Tř-1 and T-31, selected localities of the České středohoří Mountains and garnet-bearing ultramafic rocks sampled by the drillcore T-7. The contents of the major and some minor elements were determined by an electron probe microanalyzer. The garnets from the sediments were divided into 3 groups according to the contents of the end-members: 1) pyrope-, 2) almandine - pyrope- and 3) grosular - almandine-rich. Garnets from the drillcore T-7 were classified according to individual rock types in which they occurred: lherzolite, hazburgite, pyroxenite, eclogite and granulite. Chemical analyzes of garnets displayed the presence of positive correlations Cr vs. Ca vs. Ti Mn in pyrope grains. The contents of trace elements in garnets were studied by an LA-ICP-MS. After normalization to the CI-reservoir, garnets most often show lherzolite profiles of rare earth elements. Garnets of intense red and purple colors show slightly sinusoidal REE profiles. Inclusions enclosed in garnets were studied by a scanning electron microscope. If their dimensions allowed, the major and minor elements were determined by electron microanalysis for inclusions. Inclusions of amphiboles in association with spinel group minerals, carbonates and...
16

Chemická variabilita granátů z Českého středohoří a charakterizace jejich minerálních inkluzí / Chemical variability of garnets from the České středohoří Mountains and characterization of their mineral inclusions

Píšová, Barbora January 2020 (has links)
The samples of garnets used in this study come from clastic sediments from the drillcores Tř-1 and T-31, selected localities of the České středohoří Mountains and garnet-bearing ultramafic rocks sampled by the drillcore T-7. The contents of the major and some minor elements were determined by an electron probe microanalyzer. The garnets from the sediments were divided into 3 groups according to the contents of the end-members: 1) pyrope-, 2) almandine - pyrope- and 3) grosular - almandine-rich. Garnets from the drillcore T-7 were classified according to individual rock types in which they occurred: lherzolite, hazburgite, pyroxenite, eclogite and granulite. Chemical analyzes of garnets displayed the presence of positive correlations Cr vs. Ca vs. Ti Mn in pyrope grains. The contents of trace elements in garnets were studied by an LA-ICP-MS. After normalization to the CI-reservoir, garnets most often show lherzolite profiles of rare earth elements. Garnets of intense red and purple colors show slightly sinusoidal REE profiles. Inclusions enclosed in garnets were studied by a scanning electron microscope. If their dimensions allowed, the major and minor elements were determined by electron microanalysis for inclusions. Inclusions of amphiboles in association with spinel group minerals, carbonates and...
17

Social Landscapes of Transegalitarian Societies: An Analysis of the Chipped Stone Artifact Assemblage from the Crystal River Site (8CI1), Citrus County, Florida

Estabrook, Richard William 01 January 2011 (has links)
The research undertaken in this dissertation was designed to explore how the institutionalized social inequalities in prehistoric Woodland society are reflected in the differences in the procurement, in the life history, and the final discard locations of the flaked chert stone tools from the Crystal River site (8CI1). The Woodland period (1000 BC to AD 1000) was a time of both stability and change in Native American society. Many of the core institutions such as subsistence, hunting and ceramic technology, and residence remained relatively constant while religious and political institutions underwent dramatic changes. This study focuses on how these social inequalities were manifested in the chipped stone tool assemblage from this site. The Crystal River site is an Early to Middle Woodland-period mound complex located in coastal Citrus County, Florida. Dedicated as a National Historic Landmark site in 1991, the Crystal River site is internationally known and respected. Despite extensive work at the site conducted by Bullen and others during the 1940-60s, little was actually published about the material remains excavated from the site. Work resumed on the site in the 1980s and has continued as required by park maintenance and repair issues. Since 2007, remote sensing and other non-invasive technologies have been employed to advance research further at the site. This research returned to the flaked stone materials recovered during the periods 1903-1964 and 1984-2001 to illuminate site activities better without additional ground-disturbing activities. Multiple techniques were employed to develop the data sets that were used to investigate the research questions addressed in this study. The GIS-based weights-of-evidence procedure was used to predict the locations of chert outcrops within a 50 km study area. This model validated the existing quarry cluster method of determining the provenience of Florida cherts. A cost-path analysis was used to identify those chert sources that would have been most accessible to the site's inhabitants. These techniques defined a series of coastal chert outcrops that form the newly-proposed New Coastal quarry cluster. A chaîne opératoire or operational sequence approach was adopted for the analysis of the chipped stone assemblage. A waste flake analysis, a hafted biface classification, and a raw material provenience classification were conducted for all flaked-stone materials. Use-wear determinations were made using both low-power (10-70x) and high-power (50-400x) magnification analysis techniques. A life history approach was taken to the hafted biface assemblage and hafted biface retouch index (HRI) values were determined for all hafted bfaces and biface fragments. The provenience analysis demonstrated that the majority of the chert used by the inhabitants of Crystal River came from outcrops and quarries south of the site along the coastal marshes and the western margins of the Brooksville Ridge. These resources are all within a short canoe trip from the site. Two life history trajectories are suggested for the chipped stone tools from Crystal River. The majority of the chert was obtained from local sources. The second life history was defined for a small subset of the hafted bifaces that were transported from quarries located outside the core subsistence catchment of Crystal River site. Four research hypotheses were developed to test propositions related to the ways in which institutionalized social inequalities are reflected in the patterning of the chipped stone artifact assemblage at the Crystal River site. Although only some of these hypotheses were supported, the results of this investigation do support much of the research that has previously been conducted with the lithic assemblages from Woodland mound complexes in Florida. Chert acquisition is heavily reliant on local lithic sources. Chert procurement appears to be embedded in the collection of other resources. Stone tool use at the site follows the typical expedient flake tool/local raw material pattern that has been documented for other Middle Woodland sites in the region. There was no evidence to suggest that thermal alteration was used to enhance the quality of either the local cherts or those brought to the site from more distant sources. The analysis identified two distinct life histories for at least part of the stone tool assemblage. Many of the hafted bifaces, formed tools and flake tools recovered from the site were made from local cherts. These tool where likely made, used, and discarded at Crystal River. Some of the hafted bifaces and flake cores were made from cherts found on the outer edges of the 50 km study area defined for this investigation. These items were brought to the Crystal River site, used, resharpened, and broken in transit, and finally replaced by new tools at the site. The broken fragments of these tools were discarded in the midden debris to eventually become part of the archaeological record from this now-famous site.
18

Po stopách staré kresby ve sbírkách vybraných českých sběratelů / Following old master drawings within the collections of selected Czech collectors

Babická, Lenka January 2019 (has links)
Following old master drawings within the collections of selected Czech collectors Abstract This thesis is a contribution to the history of collecting in Bohemia. It deals with the collecting of drawings and tracks them within the selected collections and collectors. It focuses primarily on the old master drawings, defined as works from the 16th to the 18th century. Within the issue of collecting the attention is, even when studying specific personalities, often paid to the picture galleries rather than the print collections. Due to its fragile nature, drawing tends to fit into the background and, if it does not form the main part of the collection, is not reflected. Many of the collections and collectors have come to attention lately, but many still await their appreciation and introduction into new contexts. Keywords Collecting, collector, drawing, Old Master Drawings, Bohemia, provenance, Prokop Toman, Rudolf Kuchynka, Vincenc Kramář, Jan Krčmář, Frits Lugt
19

Vem äger konsten på svenska museer? : En kvalitativ fallstudie om samlingarnas proveniens, baserat på intervjuer av ett selekterat urval av ledande personer inom museiverksamhet i Stockholm / Who owns the art at the museums? : A qualitative case-study regarding the provenience of the art collections, based on interviews on a selection of leading management staff within museums in Stockholm

Edung, Gunnar January 2022 (has links)
No description available.
20

Obchod s mramorem v pozdně antické Ravenně: archeologický materiál z komplexu San Severo / Ravennate Marble Trade in the Late Antiquity: Material from the San Severo Complex

Tůmová, Helena January 2013 (has links)
This thesis aims to study the commercial mechanism of Ravenna in the Late Antiquity from the point of view of the amount, type and provenance of the imported stone artefacts (fragments of architectural decoration, revetments slabs, opus sectile, sarcophagi), based on the study of archaeological material from the site of the basilica and the monastery of San Severo in Classe (Ravenna). Ravenna represented an important administrative and cultural center in the 5th and 6th century, connecting western and eastern artistic influences and focusing herself on trade and production. Determination of the stone artefacts from the San Severo locality was principally based on the archaeometric methods and on the combination of archaeologic and geologic approach as well. Specific archaeometric methods (macroscopic, geochemical and mineralogical-petrographic analyses) together with a quantitative evaluation were applied. Many scientific works, dedicated till this time to the art history of late antique Ravenna and dealing also the argument of ravennate "marbles" presumed the prevailing provenance from Proconnesos and usual commercial relations between Ravenna and Constantinople as well. Constantinople played a role of a mediator of oriental localities and Ravenna. The hypothesis concerning the provenance of the...

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