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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

Granitoid geochemistry and late Archean crustal evolution in the central Slave Province /

Davis, William James, January 1991 (has links)
Thesis (Ph.D.)--Memorial University of Newfoundland, 1992. / Typescript. Bibliography: leaves 257-283. Also available online.
22

The basal gabbro subdivision and associated magmatic nickel-copper sulphide mineralization of the Pants Lake intrusion, Labrador, Canada : a combined geological, petrological, geochemical, and metallogenic study /

Smith, Roderick L., January 2006 (has links)
Thesis (M.Sc.)--Memorial University of Newfoundland, 2006. / Includes bibliographical references. Also available online.
23

Mineralogy, geochemistry, petrogenesis and structural relationships of the Aillik Bay alkaline intrusive suite, Labrador, Canada /

Foley, Stephen Francis, January 1982 (has links)
Thesis (M.Sc.)--Memorial University of Newfoundland. / Bibliography : leaves 183-205. Also available online.
24

Calcium isotope insight into the global carbon cycle

Bradbury, Harold John January 2018 (has links)
Over the course of my PhD, I developed the analytical capability to measure calcium isotopes at the University of Cambridge and analyzed calcium isotopes in a range of fluids and minerals in modern and past environments. After discussing my methodological development, I report my work in the glacial precursor to the Dead Sea. Here, the calcium isotope composition of aragonite varies synchronously with lake level fluctuations over the last 70,000 years. My numerically reconstructed lake calcium budget led me to conclude that 20,000 years ago, the Dead Sea was wetter than modern conditions, rather than colder and drier, as had previously been proposed. The primary focus of my PhD research was understanding the sedimentary sink for carbon. The formation of authigenic carbonate in marine sediments is caused by the microbial degradation of organic matter. I used pore fluid measurements and a numerical model to identify zones of authigenic carbonate precipitation. This knowledge was then combined with an understanding of the microbial processes that occur beneath the seafloor to determine the link between microbial activity and authigenic carbonate formation. Two processes, sulfate reduction and the anaerobic oxidation of methane were determined to be the main drivers of authigenic carbonate precipitation. In order to assess the importance of the carbon isotope signal imparted by each of the two identified processes, I created Artificial Neural Networks to predict the areal extent of authigenic carbonate precipitation and the dominant microbial process driving the precipitation. My ANNs identified that 37% of the modern seafloor is precipitating authigenic carbonate, which leads to a flux of 1.2*10^12 moles of carbon per year, of which 88% is due to the anaerobic oxidation of methane, and 12% is due to sulfate reduction. This represents 2-3% of the modern global carbon deposition, however I was able to show that this would be significantly higher in the geological past when ocean conditions were vastly different to how they are today. Finally, I conclude by proposing that some variations in the global carbon cycle in the past can be explored by linking marine calcium concentrations to authigenic carbonate formation and the flux of alkalinity from the seafloor.
25

Paleoproterozoic crustal evolution and Fe-Cu metallogeny of the western Yangtze Block, SW China

Zhao, Xinfu, January 2010 (has links)
Thesis (Ph. D.)--University of Hong Kong, 2010. / Includes bibliographical references (leaves 179-192). Also available in print.
26

Geological setting of the Kemess South Cu-Au porphyry deposit, British Columbia /

Rogers, Christopher January 1900 (has links)
Thesis (M.Sc.) - Carleton University, 2002. / Accompanying material: 2 maps in pocket. Includes bibliographical references (p. 119-127). Also available in electronic format on the Internet.
27

Application des techniques géostatistiques et d'analyse multivariable à l'interprétation des relevés géochimiques régionaux /

Bellehumeur, Claude. January 1992 (has links)
Thèse (D.R.Min.)-- Université du Québec à Chicoutimi, 1992. / Cette thèse a été réalisée à l'Université du Québec à Montréal dans le cadre du programme de doctorat en Ressources minérales extensionné de l'UQAC à l'UQAM. CaQCU Document électronique également accessible en format PDF. CaQCU
28

Geochemie und Geochronologie des Erongo-Komplexes, Namibia /

Wigand, Marcus, January 1900 (has links)
Thesis (doctoral)--Universität Potsdam, 2003. / "Januar 2005"--P. [2] of cover. Added thesis t.p. Includes bibliographical references (p. 82-96). Also available via the World Wide Web.
29

Geochemical and tectonic evolution of the Colorado Plateau mantle lithosphere : evidence from Grand Canyon mantle xenoliths /

Riter, Joyce Christine Alexis, January 1999 (has links)
Thesis (Ph. D.)--University of Texas at Austin, 1999. / Vita. Includes bibliographical references (leaves 337-356). Available also in a digital version from Dissertation Abstracts.
30

The geology and geochemistry of the McKay River Area volcanic rocks, western Labrador /

Noel, Nathaniel Thomas, January 1992 (has links)
Thesis (M.Sc.)--Memorial University of Newfoundland. / Folded, hand col. map in pocket. Scale 1:50 000. Typescript. Bibliography: leaves 136-143. Also available online.

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