Development of a leaching procedure for isotopic study of metal/silicate partitioning experiments
Name
1051220944-MIT.pdf
Description
Full printable version
Size
2.17 MB
Format
Adobe PDF
Checksum (MD5)
7997d04e97afa2fbceea90ff9bd1cb7b
Author(s)
Spanjers, Mary C
Advisor(s)
Timothy Grove.
Date Issued
2018
Publisher
Massachusetts Institute of Technology
Abstract
The ratio of 238U/ 235U has long been assumed to be constant and equal to 137.88. However, recent research has found that uranium fractionation occurs in a variety of environments, especially reducing environments. Fractionation in metal/silicate systems could be a contributor to Earth's geodynamo heating and affect Pb-Pb geochronology. Sixteen experimental iron/silicate samples were separated magnetically into iron and silicate fractions. Each fraction was leached with 2.5 M HCl, 10 M HCl, 10 M HCl at a higher temperature, and HF and the uranium released in each step was measured by mass spectrometry. The depleted nature of the uranium used to create the samples precludes high-precision isotope fractionation assessments. However, the effectiveness of the leaching procedure was examined for potential use on future samples. The U release pattern in silicate fractions was not consistent between all of the samples, and major element concentration measurements will allow identification of the phase being digested in each step. The contamination from silicate and graphite in the metal fractions prevents uranium from being accurately measured.
Description
Thesis: S.B., Massachusetts Institute of Technology, Department of Earth, Atmospheric, and Planetary Sciences, 2018.
Cataloged from PDF version of thesis.
Includes bibliographical references (pages 18-19).
Subjects
Earth, Atmospheric, and Planetary Sciences.
MIT Department
Massachusetts Institute of Technology. Department of Earth, Atmospheric, and Planetary Sciences
Terms of Use
MIT theses are protected by copyright. They may be viewed, downloaded, or printed from this source but further reproduction or distribution in any format is prohibited without written permission.
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