Assessing the reliability of detrital zircon in Early-Earth provenance studies
Our understanding of the Early Earth and the processes that have shaped its evolution have spawned predominantly from the geochemical and isotopic signatures of a small number of zircon populations around the world. Studies of trace element distributions, Hf and O isotope systematics as well as mine...
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Stockholms universitet, Institutionen för geologiska vetenskaper
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ftstockholmuniv:oai:DiVA.org:su-158741 2023-05-15T16:30:19+02:00 Assessing the reliability of detrital zircon in Early-Earth provenance studies Kielman, Ross 2018 application/pdf http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-158741 eng eng Stockholms universitet, Institutionen för geologiska vetenskaper Naturhistoriska riksmuseet Stockholm : Department of Geological Sciences, Stockholm University Meddelanden från Stockholms universitets institution för geologiska vetenskaper 373 orcid:0000-0003-0984-3074 http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-158741 urn:isbn:978-91-7797-386-7 urn:isbn:978-91-7797-387-4 info:eu-repo/semantics/openAccess Geology Geologi Geochemistry Geokemi Geosciences Multidisciplinary Multidisciplinär geovetenskap Doctoral thesis, comprehensive summary info:eu-repo/semantics/doctoralThesis text 2018 ftstockholmuniv 2023-02-23T21:43:18Z Our understanding of the Early Earth and the processes that have shaped its evolution have spawned predominantly from the geochemical and isotopic signatures of a small number of zircon populations around the world. Studies of trace element distributions, Hf and O isotope systematics as well as mineral inclusion chemistry in detrital zircon are combined with U-Pb chronology in order to constrain source rock characteristics. However, previous research has highlighted the potential for primary isotopic and geochemical signatures to be modified after deposition, enhanced by self-induced radiation damage and crystal-plastic deformation. Further complications arise when an unknown number of source rocks contribute to the detrital sediments, or when the source rocks are absent as is the case for Hadean detrital zircon. In this thesis, a range of analytical methods are applied to relatively uncharted ancient detrital zircon populations, in addition to a systematic investigation into the behaviour of titanium, rare earth elements, U-Th-Pb, Lu-Hf and O isotopes in a magmatic source-rock analogue to such ancient detrital zircon suites. Three localities are studied: Mt. Alfred, within the Yilgarn Craton of Western Australia (detrital study); the Saglek Block, the western-most extent of the North Atlantic Craton in northern Labrador (detrital study); and a locality south of Isua in southern West Greenland (analogue study). We have utilised a CAMECA ims 1280 Secondary Ion Mass Spectrometer (SIMS) for its high spatial resolution and small volume sampling, except for the Lu-Hf analyses which were carried out using a Laser Ablation Multicollector Inductively Coupled Plasma Mass Spectrometer (LA-MC-ICP-MS). The main outcomes of this study are threefold. 1) Heavily discordant, ancient detrital zircon populations require extensive data filtering in order to produce reliable data for age comparison. Further, age estimations of pervasive Pb loss even in metamict detrital zircon may be achieved using intragrain discordia intercept ... Doctoral or Postdoctoral Thesis Greenland North Atlantic Stockholm University: Publications (DiVA) Greenland |
institution |
Open Polar |
collection |
Stockholm University: Publications (DiVA) |
op_collection_id |
ftstockholmuniv |
language |
English |
topic |
Geology Geologi Geochemistry Geokemi Geosciences Multidisciplinary Multidisciplinär geovetenskap |
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Geology Geologi Geochemistry Geokemi Geosciences Multidisciplinary Multidisciplinär geovetenskap Kielman, Ross Assessing the reliability of detrital zircon in Early-Earth provenance studies |
topic_facet |
Geology Geologi Geochemistry Geokemi Geosciences Multidisciplinary Multidisciplinär geovetenskap |
description |
Our understanding of the Early Earth and the processes that have shaped its evolution have spawned predominantly from the geochemical and isotopic signatures of a small number of zircon populations around the world. Studies of trace element distributions, Hf and O isotope systematics as well as mineral inclusion chemistry in detrital zircon are combined with U-Pb chronology in order to constrain source rock characteristics. However, previous research has highlighted the potential for primary isotopic and geochemical signatures to be modified after deposition, enhanced by self-induced radiation damage and crystal-plastic deformation. Further complications arise when an unknown number of source rocks contribute to the detrital sediments, or when the source rocks are absent as is the case for Hadean detrital zircon. In this thesis, a range of analytical methods are applied to relatively uncharted ancient detrital zircon populations, in addition to a systematic investigation into the behaviour of titanium, rare earth elements, U-Th-Pb, Lu-Hf and O isotopes in a magmatic source-rock analogue to such ancient detrital zircon suites. Three localities are studied: Mt. Alfred, within the Yilgarn Craton of Western Australia (detrital study); the Saglek Block, the western-most extent of the North Atlantic Craton in northern Labrador (detrital study); and a locality south of Isua in southern West Greenland (analogue study). We have utilised a CAMECA ims 1280 Secondary Ion Mass Spectrometer (SIMS) for its high spatial resolution and small volume sampling, except for the Lu-Hf analyses which were carried out using a Laser Ablation Multicollector Inductively Coupled Plasma Mass Spectrometer (LA-MC-ICP-MS). The main outcomes of this study are threefold. 1) Heavily discordant, ancient detrital zircon populations require extensive data filtering in order to produce reliable data for age comparison. Further, age estimations of pervasive Pb loss even in metamict detrital zircon may be achieved using intragrain discordia intercept ... |
format |
Doctoral or Postdoctoral Thesis |
author |
Kielman, Ross |
author_facet |
Kielman, Ross |
author_sort |
Kielman, Ross |
title |
Assessing the reliability of detrital zircon in Early-Earth provenance studies |
title_short |
Assessing the reliability of detrital zircon in Early-Earth provenance studies |
title_full |
Assessing the reliability of detrital zircon in Early-Earth provenance studies |
title_fullStr |
Assessing the reliability of detrital zircon in Early-Earth provenance studies |
title_full_unstemmed |
Assessing the reliability of detrital zircon in Early-Earth provenance studies |
title_sort |
assessing the reliability of detrital zircon in early-earth provenance studies |
publisher |
Stockholms universitet, Institutionen för geologiska vetenskaper |
publishDate |
2018 |
url |
http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-158741 |
geographic |
Greenland |
geographic_facet |
Greenland |
genre |
Greenland North Atlantic |
genre_facet |
Greenland North Atlantic |
op_relation |
Meddelanden från Stockholms universitets institution för geologiska vetenskaper 373 orcid:0000-0003-0984-3074 http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-158741 urn:isbn:978-91-7797-386-7 urn:isbn:978-91-7797-387-4 |
op_rights |
info:eu-repo/semantics/openAccess |
_version_ |
1766020046931361792 |