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dc.contributor.advisorAnsdell, Kevinen_US
dc.contributor.advisorAnnesley, Irvineen_US
dc.creatorMillar, Roberten_US
dc.date.accessioned2016-01-28T12:00:16Z
dc.date.available2016-01-28T12:00:16Z
dc.date.created2015-12en_US
dc.date.issued2016-01-27en_US
dc.date.submittedDecember 2015en_US
dc.identifier.urihttp://hdl.handle.net/10388/ETD-2015-12-2377en_US
dc.description.abstractThe eastern margin of the Proterozoic Athabasca Basin in northern Saskatchewan is host to several of the highest-grade unconformity-related (U/C-related) uranium deposits in the world. Many researchers agree that uranium deposition occurred due to oxidized basinal brines transporting uranium mixing with reducing fluids or interacting with reduced rock causing uranium to precipitate, although the source of the uranium is still an unresolved and highly debated subject. Boron isotopic signatures, preserved in refractory minerals such as tourmaline, can aid in determining the source of fluids and P-T conditions during crystallization whereas lithium isotopic fractionation is indicative of weathering, hydrothermal alteration, and/or igneous and metamorphic processes. For this study a suite of fresh to strongly altered basement samples were selected from multiple sites below the eastern Athabasca Basin to measure the bulk delta7Li, delta11B and Pb-Pb isotopic signatures. Kinetic modelling of the Li and B isotopic systems suggest that both systems are slightly conservative of their original fluid reservoir, and by calculating the Damkohler numbers (ND) it is predicted that delta11B will be more indicative of the fluid source whereas lithium isotopes will equilibrate over shorter distance. However, both isotopic systems will fractionate with large concentration changes. Significant variations were observed for both delta7Li and delta11B, delta7Li values ranged from 0 to 14 ‰, the range in delta7Li was interpreted to be representative of both partial melting of metasediments to form granitic pegmatites and hydrothermal fluids. In comparison the range for delta11B was much larger from -16 to +17‰, within the dataset there appeared to be regional isotopic differences but unfortunately this dataset was too small to determine regional isotopic patterns. For each region the delta11B for the pegmatites was often heavier than the metasedimentary samples suggesting a metasedimentary source for the granitic pegmatites. Elevated U concentrations and decreasing 207Pb/206Pb ratios in both altered and unaltered samples suggest radiogenic Pb and U are present both in the basement and in fluids transporting U through the basement. Partial digestion 207Pb/206Pb ratios range from the common 207Pb/206Pb ratios of 0.7 to radiogenic 207Pb/206Pb ratios of 0.1. The radiogenic 207Pb/206Pb are indicative of either resetting of residual material during fluid migration or radiogenic fluids sources interacting with the rocks of this study.en_US
dc.language.isoengen_US
dc.subjectUnconformity-related uranium depositsen_US
dc.subjectBoron isotopesen_US
dc.subjectLithium isotopesen_US
dc.subjectAthabasca Basinen_US
dc.titleLithium, Boron and Pb-Pb Isotopic Signatures of the Basement Lithologies Underlying the Eastern Athabasca Basinen_US
thesis.degree.departmentGeological Sciencesen_US
thesis.degree.disciplineGeologyen_US
thesis.degree.grantorUniversity of Saskatchewanen_US
thesis.degree.levelMastersen_US
thesis.degree.nameMaster of Science (M.Sc.)en_US
dc.type.materialtexten_US
dc.type.genreThesisen_US
dc.contributor.committeeMemberEglington, Bruceen_US
dc.contributor.committeeMemberLindsay, Matten_US
dc.contributor.committeeMemberFayek, Mostafaen_US


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