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dc.contributor.advisorNabelek, Peter Igoreng
dc.contributor.authorGross, Martin Benjamineng
dc.coverage.spatialBlack Hills (S.D. and Wyo.)eng
dc.date.issued2014eng
dc.date.submitted2014 Springeng
dc.description"May 2014."eng
dc.descriptionThesis supervisor: Dr. Peter I. Nabelek.eng
dc.description.abstractExtremely large elongated crystals, attributed to low nucleation rates and rapid growth during fast cooling (Nabelek et al., 2010), are just one example of the intriguing and unusual disequilibrium features found in granitic pegmatites. Lithium isotope ratios are no exception. Previous studies have shown pegmatites to have signicantly elevated [delta]?�?Li compared to normal crustal values and large variations across individual pegmatite intrusions (Teng et al., 2006, Maloney et al., 2008). Variable and extreme isotope fractionation has been linked to kinetics of crystallization, dierential diusion of [delta]?�?Li and [delta]?�?Li, fractional crystallization, and interaction with fluids. Although a number of isotopic studies of pegmatites exist at the outcrop scale, studies on single crystals are rare. A study by Ludwig et al. (2011) showed a roughly homogenous isotope profile in a tourmaline using secondary ion mass spectroscopy. If, however, Li isotope ratios are in fact variable within individual crystals, the variability has implications for crystallization processes in leucogranite and pegmatite dikes. For this study, tourmaline crystals were collected from several texturally different pegmatite localities in the large, Proterozoic leucogranite-pegmatite field in the Black Hills, SD. Lithium concentrations and isotope ratios were measured at numerous points along the lengths of individual tourmaline crystals. Slices of tourmalines, cut perpendicular to the crystal's long axis, were dissolved by an alkali fusion technique. Concentrations were determined at the University of Missouri using a Perkin-Elmer Optima 3300 ICP-OES. Isotope measurements were performed at University of Maryland-College Park using a Nu Plasma Multi-collector ICP-MS. Purication followed the three-column cation exchange chromatography method (Moriguti and Nakamura, 1998). Mapping of major elements was performed on slices of one sample using the JEOL JXA-8200 Superprobe at Washington University in St. Louis. Results reveal exteng
dc.description.bibrefIncludes bibliographical references (pages 64-72).eng
dc.format.extent1 online resource (ix, 72 pages) : illustrations (some color), mapseng
dc.identifier.merlinb106938617eng
dc.identifier.oclc900021948eng
dc.identifier.urihttps://hdl.handle.net/10355/44273
dc.identifier.urihttps://doi.org/10.32469/10355/44273eng
dc.languageEnglisheng
dc.publisherUniversity of Missouri--Columbiaeng
dc.relation.ispartofcommunityUniversity of Missouri-Columbia. Graduate School. Theses and Dissertations. These. 2014 Theses. 2014 Freely available theseseng
dc.subjectAuthor supplied: tourmaline, lithium, isotopes, fractionation, black hills, harney peakeng
dc.subject.lcshTourmalineeng
dc.subject.lcshIgneous rockseng
dc.subject.lcshLithium -- Isotopeseng
dc.titleVariation and fractionation of lithium isotopes within single tourmaline crystals in the pegmatites of the Black Hills, SDeng
dc.title.alternativeVariation and fractionation of lithium isotopes within single tourmaline crystals in the pegmatites of the Black Hills, South Dakotaeng
dc.typeThesiseng
thesis.degree.disciplineGeological sciences (MU)eng
thesis.degree.grantorUniversity of Missouri--Columbiaeng
thesis.degree.levelMasterseng
thesis.degree.nameM.S.eng


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