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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.
41

Préhistoire de la Moyenne-Côte-Nord : le chert de la Minganie et l’utilisation des ressources lithiques

Ouellet, Jean-Christophe 12 1900 (has links)
Ce mémoire traite de l’utilisation des matières premières lithiques telle que représentée sur les sites préhistoriques de la Moyenne-Côte-Nord du Golfe du Saint-Laurent, au Québec. Cette étude régionale se base sur la réanalyse d’un nombre important de collections archéologiques et accorde une grande importance à l’identification et à la description des matières premières utilisées. Un matériau d’origine locale, le Chert de la Minganie, y occupe une place particulière. L’importance de ce matériau pour la préhistoire régionale était jusqu’ici virtuellement inconnue. Suite à nos analyses, un inventaire complet des matières premières utilisées est mis sur pied. Ces données mettent en évidence un certain nombre de comportements. Principalement, nous identifions deux ensembles qui illustrent la présence de territoires attribuables à la répartition de groupes amérindiens subrégionaux (bandes). Finalement, à travers l’utilisation des ressources lithiques, les liens qui rattachent les groupes de notre région d’étude à ceux de la péninsule du Québec-Labrador sont illustrés. / This thesis deals with lithic raw material use as evidenced on prehistoric sites from the middle North Shore of the Saint Lawrence River, Quebec. This regional study is based on the reanalysis of a large number of archaeological collections and places central importance on the identification and description of the varieties of lithics that were used. A specific material of local origin, Mingan chert, occupies a special place in this study. The importance of this material for regional prehistory has remained, until now, poorly understood. As a result of our analyses, a full inventory of the lithic varieties used on these sites is presented and permits us to illustrate certain prehistoric behaviours. Principally, we identify two sets of sites which correspond to the presence of subregional aboriginal groups (bands). Finally, raw material use demonstrates social and exchange ties that link the groups of our study area to those of the broader region of the Quebec-Labrador peninsula.
42

Coal seam gas associations in the Huntly, Ohai and Greymouth regions, New Zealand

Butland, Caroline January 2006 (has links)
Coal seam gas has been recognised as a new, potential energy resource in New Zealand. Exploration and assessment programmes carried out by various companies have evaluated the resource and indicated that this unconventional gas may form a part of New Zealand's future energy supply. This study has delineated some of the controls between coal properties and gas content in coal seams in selected New Zealand locations. Four coal cores, one from Huntly (Eocene), two from Ohai (Cretaceous) and one from Greymouth (Cretaceous), have been sampled and analysed in terms of gas content and coal properties. Methods used include proximate, sulphur and calorifc value analyses; ash constituent determination; rank assessment; macroscopic analysis; mineralogical analysis; maceral analysis; and gas analyses (desorption, adsorption, gas quality and gas isotopes). Coal cores varied in rank from sub-bituminous B-A (Huntly); sub-bituminous C-A (Ohai); and high volatile bituminous A (Greymouth). All locations contained high vitrinite content (~85 %) with overall relatively low mineral matter observed in most samples. Mineral matter consisted of both detrital grains (quartz in matrix material) and infilling pores and fractures (clays in fusinite pores; carbonates in fractures). Average gas contents were 1.6 m3/t in the Huntly core, 4.7 m3/t in the Ohai cores, and 2.35 m3/t in the Greymouth core. The Ohai core contained more gas and was more saturated than the other cores. Carbon isotopes indicated that the Ohai gas composition was more mature, containing heavier 13C isotopes than either the Huntly or Greymouth gas samples. This indicates the gas was derived from a mixed biogenic and thermogenic source. The Huntly and Greymouth gases appear to be derived from a biogenic (by CO2 reduction) source. The ash yield proved to be the dominant control on gas volume in all locations when the ash yield was above 10 %. Below 10 % the amount of gas variation is unrelated to ash yield. Although organic content had some influence on gas volume, associations were basin and /or rank dependant. In the Huntly core total gas content and structured vitrinite increased together. Although this relationship did not appear in the other cores, in the Ohai SC3 core lost gas and fusinite are associated with each other, while desmocollinite (unstructured vitrinite) correlated positively with residual gas in the Greymouth core. Although it is generally accepted that higher rank coals will have higher adsorption capacities, this was not seen in this data set. Although the lowest rank coal (Huntly) contains the lowest adsorption capacity, the highest adsorption capacity was not seen in the highest rank coal (Greymouth), but in the Ohai coal instead. The Ohai core acted like a higher rank coal with respect to the Greymouth coal, in terms of adsorption capacity, isotopic signatures and gas volume. Two hypothesis can be used to explain these results: (1) That a thermogenically derived gas migrated from down-dip of the SC3 and SC1 drill holes and saturated the section. (2) Rank measurements (e.g. proximate analyses) have a fairly wide variance in both the Greymouth and Ohai coal cores, thus it maybe feasible that the Ohai cores may be higher rank coal than the Greymouth coal core. Although the second hypothesis may explain the adsorption capacity, isotopic signatures and the gas volume, when the data is plotted on a Suggate rank curve, the Ohai coal core is clearly lower rank than the Greymouth core. Thus, pending additional data, the first hypothesis is favoured.
43

Petrology and Sedimentology of the Morrissey Formation (Kootenay Group), southeast British Columbia - Southwest Alberta

Hogg, John Richard 04 1900 (has links)
<p> The Morrissey Formation of the Kootenay Group was mapped and sampled in three outcrops in southwestern Alberta and southeastern British Columbia; Burnt Ridge and Sparwood Ridge in British Columbia and Adanac Mine sight in Alberta. </p> <p> The lowest unit mapped was within the upper Fernie Formation (Passage beds) and consists of interbeds of sandstone and siltstone that were deposited as shallow water marine sediments. </p> <p> The Morrissey Formation conformably overlies the Fernie Formation and contains two members; the Weary Ridge Member and the Moose Mountain Member. The Weary Ridge Member consists of fine to medium grain, parallel and trough crossbedded sandstone, that was deposited as a delta-front-sand facies produced by coalescing of delta-sands from three to four delta complexes. The overlying Moose Mountain Member consists of high angle trough crossbedded, coarse grain, "salt and pepper" sandstone representing a distributary mouth bar environment. The Moose Mountain Member is unconventional in that the upper portion contains two units not seen in other sections. A marine trace fossil unit and a beach unit are both found within the upper portion of the member. These two units represent a transgression caused by channel switching and a regression and reworking of sediments into a beach respectively. </p> <p> Above the Morrissey Formation are the continental coals and fluvial systems of the Mist Mountain Formation. </p> <p> Petrographic studies on twenty five thin sections show two sedimentary sources for the Formation. The first source being chert rich Upper Paleozoic carbonates and the second source is Lower Paleozoic clastics that have previously been derived from a metamorphic complex of the Canadian Shield. The sandstones are cemented by quartz syntaxial overgrowths implying that there was a moderate degree of pressure solution, indicating a fairly high overburden pressure during diagenesis. </p> / Thesis / Bachelor of Science (BSc)
44

Anfore africane tardorepubblicane e primoimperiali dal Nuovo Mercato Testaccio a Roma : tipo-cronologia, ipotesi di provenienza e diffusione nel Mediterraneo / Les amphores africaines tardo républicaines et du Haut-Empire du Nuovo Mercato Testaccio à Rome : typo-chronologie, hypothèses de provenance et diffusion en Méditerranée / Late-republican and first-imperial African Amphorae from the Nuovo Mercato Testaccio in Rome : typo-chronology, origin hypothesis and distribution on the Mediterranean basin

Contino, Alessia 25 November 2015 (has links)
La recherche a été menée sur les amphores d’origine africaine produites entre le milieu du IIe siècle av. J. C. et la fin du Ier-début du IIe siècle apr. J. C. et prend son origine dans l’étude du mobilier provenant des fouilles d’archéologie urbaine réalisées à Rome, dans le quartier du Testaccio, dans les années 2005-2009. Les amphores sélectionnées ont été celles de production de tradition punique, africaine (où présumée africaine) et tripolitaine. En particulier la catégorie d’amphores appelées amphores africaines précoces, fait encore l'objet de beaucoup de doutes, en l'absence de recherches systématiques. L'étude a permis de proposer une nouvelle reconstruction générale de l'évolution typologique des amphores et des dynamiques chronologiques et commerciales du Ier siècle de l'Empire romain, en enrichissant la connaissance de leur diffusion à Rome. L’étude peut offrir une première reconstruction générale, à travers une recherche systématique, de l'évolution typologique et chronologique, de la production (les ateliers des premières phases productives de l’époque romaine ne sont presque pas connus par rapport à ceux des époques successives, à partir du IIe siècle) et de la diffusion dans le bassin de la Méditerranée en contribuant à éclaircir les dynamiques commerciales et productives du premier siècle de l'Empire romaine. En particulier cette étude a permis de comprendre que l’origine des amphores africaines précoces est désormais à placer dans le nord-ouest de la Tunisie, redonnant toute sa place a une région relativement délaissée par les études récentes, bien que elle était la premier zone de colonisation de l’Afrique romaine. / The research is pointed on the ancient african amphorae coming from the excavation of Nuovo Mercato Testaccio, carried out between 2005 and 2009 in Rome. In particular, beside the punique and tripolitanian types as so called Dressel 18, Schoene-Mau 40, Schoene-Mau 35 and Tripolitanian amphora first-second, the research is focused on the type Dressel 26, Ancient Tripolitanian amphora and Ostia 59 and 23, at the moment less known in terms of typology, production and diffusion.The quite strong presence of those amphorae in the excavation of Nuovo Mercato Testaccio has been the “start” for this research. The aims of the research are: define the typological evolution and origin of the early african amphorae; reconstruct the commercial flux of african goods to Rome in the 1st century A.D.; analyze the contents of amphorae with gascromatography (we already analyze nine samples); The present research implement the typological study of early african amphorae and, with the support of petrographic analysis, contribute to clarify origin and chronology of amphorae. The study try to give back an image of the presence of those amphorae across the Mediterranean and in Rome from the 2nd century B.C. to the 1st century A.D. One of the most important results of this study is to identify the origin of Early African Amphorae in Northern-Tunisia. In conclusion the research contribute to highlight the trade of african goods in the Mediterranean basin and in Rome from half II B.C. to end of I A.D.-beginning of II A.D.
45

Evaluación de la calidad del concreto hidráulico usando agregado fino marginal en el proyecto rehabilitación y mejoramiento de la carretera DV. Imperial – Pampas

Paredes Carrasco, Alexander Edward, Guillen Herrera, Edson Rodolfo January 2015 (has links)
Para la presente investigación de tesis desarrollada entre los distritos de Imperial y Pampas, provincia de Tayacaja, en el departamento de Huancavelica, se tiene como unidad de análisis a 60 muros de contención, donde se aplicó criterios muestréales de 23 muros f´c 210 kg/cm2. Como resultados alcanzados se logró elaborar concreto hidráulico de calidad usando agregado fino marginal con el cual se pudo satisfacer los parámetros de resistencia y durabilidad. Para demostrar la durabilidad se realizaron distintos ensayos; los que no cumplieron con las especificaciones de la norma EG-2000 fueron el de Equivalente de arena MTC E 114, Material que pasa el Tamiz N°200 MTC E 202 y Análisis granulométrico por tamizado ASTM C 136, por lo cual se efectuaron análisis más rigurosos como: el ensayo de Valor de azul de metileno y el ensayo de Análisis petrográfico macroscópico y microscópico en agregados para concreto ASTM C 295, donde se obtuvo como resultado que la arena no presenta elementos activos en su composición, lo que quiere decir que ante las condiciones ambientales de la zona estos elementos no se expanden ni se contraen y adicionalmente como medida de control se diseñó la mezcla de concreto hidráulico con aditivo incorporador de aire AirMix-200. Del mismo informe petrográfico se concluyó que la composición principal del agregado es la caliza, la cual es materia prima para la elaboración del cemento, que de alguna manera adicional ayuda a cumplir satisfactoriamente el parámetro de resistencia. Así mismo quedó demostrado que a través de ensayos a compresión no confinada de testigos de concreto, se alcanzó resistencias superiores a lo requerido en la norma EG-2000. Research for this thesis developed between the districts of Imperial and Pampas, Tayacaja province, in the department of Huancavelica, it has the analysis unit 60 retaining walls, where 23 sample criteria applied walls f´c 210 kg/cm2. Results obtained are as elaborate hydraulic concrete achievement of marginal quality using fine aggregate with which it was able to satisfy the parameters of strength and durability. To demonstrate the durability various tests were performed; those who do not comply with the specifications of the EG-2000 were rule the sand equivalent MTC E 114, passes what material the sieve No. 200 MTC E 202 and sieve analysis ASTM C 136, here by which they were made Analysis More rigorous like: The test value of methylene blue and testing of macroscopic and microscopic petrographic analysis in paragraph aggregate concrete ASTM C 295, where it resulted the sand without presents elements active in their composition, which means they say to the area Environmental Conditions These elements do not expand or contract and additionally as a control measure of self-design hydraulic concrete mix with entraining admixture AirMix-200 air. Same petrographic report concluded that the composition of the director of aggregate is limestone, which is a raw material for the production of cement, which in some additionally helps one perform satisfactorily resistance parameter. Also it demonstrated that one through essays of unconfined compressive concrete witness, higher strengths than required was reached in the EG-2000 standard.

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