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

Lingulídeos da sucessão devoniana da Bacia do Paraná, região dos Campos Gerais, Brasil: revisão de conceitos biológicos-ecológicos e análise tafonômica básica

Zabini, Carolina January 2007 (has links)
A presente dissertação aborda questões relacionadas aos fósseis de lingulídeos da Sucessão devoniana da Bacia do Paraná, região dos Campos Gerais, PR, Brasil. Para a construção da análise tafonômica básica adotou-se metodologia de coleta de alta resolução, contando com um total de valvas de aproximadamente 2.300. Aspectos referentes à biologia e ecologia de lingulídeos atuais foram levantados e descritos em conjunto a considerações relativas aos fósseis. Realizou-se análise de composição química (EDS) de rochas e de valvas, na intenção de se obter os tipos de fossilização ocorrentes, que resultou na confirmação de fossilização na forma de moldes, impressões e substituições. Na análise tafonômica básica foi possível constatar a ocorrência de morte catastrófica; são raras as ocorrências de lingulídeos em aparente posição de vida; valvas inteiras e fragmentadas foram preservadas; dúvidas permanecem em relação ao grau de autoctonia / aloctonia dos bioclastos; na comparação entre a quantidade de lingulídeos ocorrentes em diferentes afloramentos observou-se a ausência de representantes da Província Malvinocáfrica, quando da abundância de lingulídeos. / The present paper approaches questions related to fossil lingulides that are present in de Devonian Sucession of the Paraná Basin, Campos Gerais region, Paraná state, Brazil. For the construction of the basic taphonomic analysis, approximately 2.300 fossil valves were collected, with a methodology of high resolution. Aspects related to the biology and ecology of extant lingulides were described associated with conjectures about the fossils. An analysis of chemical composition (EDS) was made on the rocks and valves, to know the type of fossilization that occurred on the material; from this analysis resulted the following types: molds, impressions and substituitions. The basic taphonomic analysis showed the following assertions: the occurrence of catastrophic death; that the occurrences of lingulids in life position are rare; the occurrence of valves completes and also fragments; none decisive conclusions were made about de degrees of autoctony / aloctony of the fossils. On the comparison between different outcrops, was noted an absence of Malvinokaffric representants when the lingulids were present in abundance.
2

Lingulídeos da sucessão devoniana da Bacia do Paraná, região dos Campos Gerais, Brasil: revisão de conceitos biológicos-ecológicos e análise tafonômica básica

Zabini, Carolina January 2007 (has links)
A presente dissertação aborda questões relacionadas aos fósseis de lingulídeos da Sucessão devoniana da Bacia do Paraná, região dos Campos Gerais, PR, Brasil. Para a construção da análise tafonômica básica adotou-se metodologia de coleta de alta resolução, contando com um total de valvas de aproximadamente 2.300. Aspectos referentes à biologia e ecologia de lingulídeos atuais foram levantados e descritos em conjunto a considerações relativas aos fósseis. Realizou-se análise de composição química (EDS) de rochas e de valvas, na intenção de se obter os tipos de fossilização ocorrentes, que resultou na confirmação de fossilização na forma de moldes, impressões e substituições. Na análise tafonômica básica foi possível constatar a ocorrência de morte catastrófica; são raras as ocorrências de lingulídeos em aparente posição de vida; valvas inteiras e fragmentadas foram preservadas; dúvidas permanecem em relação ao grau de autoctonia / aloctonia dos bioclastos; na comparação entre a quantidade de lingulídeos ocorrentes em diferentes afloramentos observou-se a ausência de representantes da Província Malvinocáfrica, quando da abundância de lingulídeos. / The present paper approaches questions related to fossil lingulides that are present in de Devonian Sucession of the Paraná Basin, Campos Gerais region, Paraná state, Brazil. For the construction of the basic taphonomic analysis, approximately 2.300 fossil valves were collected, with a methodology of high resolution. Aspects related to the biology and ecology of extant lingulides were described associated with conjectures about the fossils. An analysis of chemical composition (EDS) was made on the rocks and valves, to know the type of fossilization that occurred on the material; from this analysis resulted the following types: molds, impressions and substituitions. The basic taphonomic analysis showed the following assertions: the occurrence of catastrophic death; that the occurrences of lingulids in life position are rare; the occurrence of valves completes and also fragments; none decisive conclusions were made about de degrees of autoctony / aloctony of the fossils. On the comparison between different outcrops, was noted an absence of Malvinokaffric representants when the lingulids were present in abundance.
3

Lingulídeos da sucessão devoniana da Bacia do Paraná, região dos Campos Gerais, Brasil: revisão de conceitos biológicos-ecológicos e análise tafonômica básica

Zabini, Carolina January 2007 (has links)
A presente dissertação aborda questões relacionadas aos fósseis de lingulídeos da Sucessão devoniana da Bacia do Paraná, região dos Campos Gerais, PR, Brasil. Para a construção da análise tafonômica básica adotou-se metodologia de coleta de alta resolução, contando com um total de valvas de aproximadamente 2.300. Aspectos referentes à biologia e ecologia de lingulídeos atuais foram levantados e descritos em conjunto a considerações relativas aos fósseis. Realizou-se análise de composição química (EDS) de rochas e de valvas, na intenção de se obter os tipos de fossilização ocorrentes, que resultou na confirmação de fossilização na forma de moldes, impressões e substituições. Na análise tafonômica básica foi possível constatar a ocorrência de morte catastrófica; são raras as ocorrências de lingulídeos em aparente posição de vida; valvas inteiras e fragmentadas foram preservadas; dúvidas permanecem em relação ao grau de autoctonia / aloctonia dos bioclastos; na comparação entre a quantidade de lingulídeos ocorrentes em diferentes afloramentos observou-se a ausência de representantes da Província Malvinocáfrica, quando da abundância de lingulídeos. / The present paper approaches questions related to fossil lingulides that are present in de Devonian Sucession of the Paraná Basin, Campos Gerais region, Paraná state, Brazil. For the construction of the basic taphonomic analysis, approximately 2.300 fossil valves were collected, with a methodology of high resolution. Aspects related to the biology and ecology of extant lingulides were described associated with conjectures about the fossils. An analysis of chemical composition (EDS) was made on the rocks and valves, to know the type of fossilization that occurred on the material; from this analysis resulted the following types: molds, impressions and substituitions. The basic taphonomic analysis showed the following assertions: the occurrence of catastrophic death; that the occurrences of lingulids in life position are rare; the occurrence of valves completes and also fragments; none decisive conclusions were made about de degrees of autoctony / aloctony of the fossils. On the comparison between different outcrops, was noted an absence of Malvinokaffric representants when the lingulids were present in abundance.
4

Sedimentologic and taphonomic analysis of a 1945 tsunami deposit in Sur Lagoon, Sultanate of Oman

Donato , Simon Vincent 01 1900 (has links)
The Sultanate of Oman is a rapidly modernizing country with a significant length of its coastline slated for development. Much of the coastline is still in its natural state and basic studies describing the sedimentary systems need to be conducted in order to plan effectively for their sustainable development and to monitor changes in them with time. For such purposes, sediment samples (surface and sub-surface), elevation data, and serial sediment cores were collected at Sur Lagoon during three field seasons. The research objectives, procedures, results, and analyses for Sur lagoon are presented in three chapters. The first chapter compares textural facies, identified on the basis of particle-size distribution (PSD) of surface sediments from Sur Lagoon and evaluated using multi-variate cluster analysis, for their value in recognizing modem sedimentary environments. Clustering the full PSD size spectrum (0.0375- 1888 μm) shows that facies identification is possible is closely tied to surface elevation, particle-size decreasing with increasing elevation above mean sea level. This analytical technique should be tested under different conditions to assess further its utility. The second chapter discusses the taphonomically distinct and laterally extensive (> 1 km2) bivalve shell bed deposited by a tsunami on November 28th, 1945. Taphonomic characteristics of this unit are compared to those of the shell-rich tsunamite from Caesarea, Israel, and resulted in the identification of three generic, tsunamigenic-specific traits in shell beds: 1) thickly bedded and laterally extensive shell deposit, 2) presence of allochthonous articulated bivalves not in life position, and 3) extensive angular fragmentation. When these three traits are found together, a tsunamigenic origin should be considered for the shell bed. The third chapter analyzes the PSD of the tsunamite in eight sediment cores for digested and undigested samples. Cluster analysis of the PSD extended the upper or lower tsunamite contacts in four cores, but in general, the tsunamite thickness is consistent with the previously identified shell beds (Chapter 3). The tsunamigenic processes that resulted in the deposition of the shell bed were complex, and deposition occurred during run-up, flooding, and backwash stages of the tsunami, incorporating marine, lagoonal, and terrestrial (wadi) sediment into the tsunamite. The results of this study provide baseline sedimentological data for an understudied region of the world. New applications of cluster analysis of PSD and taphonomic analysis have the potential to identify previously unknown tsunamites in the geological record, and lithological facies using textural analysis. / Thesis / Doctor of Philosophy (PhD)

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