ERA

Download the full-sized PDF of Understanding the alteration of the Tagish Lake meteorite through mineralogy, geochemistry and oxygen isotopesDownload the full-sized PDF

Analytics

Share

Permanent link (DOI): https://doi.org/10.7939/R39M4C

Download

Export to: EndNote  |  Zotero  |  Mendeley

Communities

This file is in the following communities:

Graduate Studies and Research, Faculty of

Collections

This file is in the following collections:

Theses and Dissertations

Understanding the alteration of the Tagish Lake meteorite through mineralogy, geochemistry and oxygen isotopes Open Access

Descriptions

Other title
Subject/Keyword
Tagish Lake meteorite
alteration
Type of item
Thesis
Degree grantor
University of Alberta
Author or creator
Blinova, Alexandra I
Supervisor and department
Herd, Christopher (Earth and Atmospheric Sciences)
Examining committee member and department
Brearley, Adrian (Earth and Planetary Sciences, University of New Mexico)
Stern, Richard (Earth and Atmospheric Sciences)
Heaman, Larry (Earth and Atmospheric Sciences)
Herd, Christopher (Earth and Atmospheric Sciences)
Chako, Tom (Earth and Atmospheric Sciences)
Department
Department of Earth and Atmospheric Sciences
Specialization

Date accepted
2013-09-26T13:45:34Z
Graduation date
2013-11
Degree
Doctor of Philosophy
Degree level
Doctoral
Abstract
Our understanding of the origin and formation of the various components of meteorites, and ultimately understanding the formation of the early Solar System, comes from our knowledge of the asteroidal alteration processes and modifications that such processes induce on these components. The majority of our knowledge in this area comes from the meteorites that have been subjected to some kind of terrestrial modification which has partly or completely erased any prior history of its components. Meteorites unaffected by terrestrial modification are rare but invaluable. Tagish Lake is one such meteorite; due to its fall history it is considered to be the best candidate for studying the alteration history of the asteroidal parent body. Four samples (TL5b, TL11h, TL11i, and TL11v) from the pristine collection of the Tagish Lake meteorite were studied to characterize and understand its alteration history. Based on petrological and mineralogical observations I conclude that the Tagish Lake parent body was a heterogeneous mixture of anhydrous precursors of nebular origin, which were brecciated and aqueously altered to various degree. The degree to which the studied samples experienced aqueous alteration is in the order TL5b < TL11h < TL11i. Specimen TL11v, which consists of disaggregated material, is heterogeneous on the microscale and encompasses the petrologic characteristics of other three specimens as seen through EPMA observation. The whole-rock geochemistry confirms the inferred alteration sequence observed through mineralogy. There is a positive correlation with aqueously mobile trace elements, such as K, Ba, and Br, which appear to be controlled by an increase of phyllosilicates from least to most altered samples. Yet, the homogeneity of other elements suggests that elemental mass transfer occurred on a localized scale and aqueous alteration was isochemical for these elements. Oxygen isotopic results from my study corroborate the conclusion that the range of variations observed in the Tagish Lake meteorite covers the oxygen isotopic composition seen in all other carbonaceous chondrites. Such variation found in one meteorite suggests that the Tagish Lake parent asteroid sampled the material from different oxygen isotope reservoirs, perhaps 16O-rich and 17O-rich gaseous reservoirs.
Language
English
DOI
doi:10.7939/R39M4C
Rights
Permission is hereby granted to the University of Alberta Libraries to reproduce single copies of this thesis and to lend or sell such copies for private, scholarly or scientific research purposes only. Where the thesis is converted to, or otherwise made available in digital form, the University of Alberta will advise potential users of the thesis of these terms. The author reserves all other publication and other rights in association with the copyright in the thesis and, except as herein before provided, neither the thesis nor any substantial portion thereof may be printed or otherwise reproduced in any material form whatsoever without the author's prior written permission.
Citation for previous publication

File Details

Date Uploaded
Date Modified
2014-04-25T00:09:38.256+00:00
Audit Status
Audits have not yet been run on this file.
Characterization
File format: pdf (Portable Document Format)
Mime type: application/pdf
File size: 14451066
Last modified: 2015:10:12 12:24:37-06:00
Filename: Blinova_Alexandra_Fall2013.pdf
Original checksum: 638b98efde10228388029a6e6eb3a9f7
Well formed: true
Valid: true
Status message: File header gives version as 1.4, but catalog dictionary gives version as 1.3
File title: Microsoft Word - Complete_thesis_final.docx
File author: Alexandra Blinova
Page count: 153
Activity of users you follow
User Activity Date