Integrated Pb- and S-isotope investigation of sulphide minerals from the early Archaean of southwest Greenland
We present high-spatial resolution secondary ion mass spectrometry (SIMS) measurements of Pb and S isotopes in sulphides from early Archaean samples at two localities in southwest Greenland. Secondary pyrite from a 3.71 Ga sample of magnetite-quartz banded iron formation in the Isua Greenstone Belt,...
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ftqueensland:oai:eprints.qut.edu.au:126251 2024-05-12T08:04:27+00:00 Integrated Pb- and S-isotope investigation of sulphide minerals from the early Archaean of southwest Greenland Whitehouse, M. J. Kamber, B. S. Fedo, C. M. Lepland, A. 2005 https://eprints.qut.edu.au/126251/ unknown Elsevier doi:10.1016/j.chemgeo.2005.06.004 Whitehouse, M. J., Kamber, B. S., Fedo, C. M., & Lepland, A. (2005) Integrated Pb- and S-isotope investigation of sulphide minerals from the early Archaean of southwest Greenland. Chemical Geology, 222(1-2), pp. 112-131. https://eprints.qut.edu.au/126251/ Science & Engineering Faculty; Australian Research Centre for Aerospace Automation Consult author(s) regarding copyright matters This work is covered by copyright. Unless the document is being made available under a Creative Commons Licence, you must assume that re-use is limited to personal use and that permission from the copyright owner must be obtained for all other uses. If the document is available under a Creative Commons License (or other specified license) then refer to the Licence for details of permitted re-use. It is a condition of access that users recognise and abide by the legal requirements associated with these rights. If you believe that this work infringes copyright please provide details by email to qut.copyright@qut.edu.au Chemical Geology secondary ion mass spectrometer Pb isotopes S isotopes Archaean Greenland southern west greenland isua greenstone-belt itsaq gneiss complex earths earliest life crustal evolution microprobe analysis supracrustal belt amitsoq gneisses terrestrial lead ion-microprobe Geochemistry & Geophysics Contribution to Journal 2005 ftqueensland https://doi.org/10.1016/j.chemgeo.2005.06.004 2024-04-17T14:24:35Z We present high-spatial resolution secondary ion mass spectrometry (SIMS) measurements of Pb and S isotopes in sulphides from early Archaean samples at two localities in southwest Greenland. Secondary pyrite from a 3.71 Ga sample of magnetite-quartz banded iron formation in the Isua Greenstone Belt, which has previously yielded unradiogenic Pb consistent with its ancient origin, contains sulphur with a mass independently fractionated (MIF) isotope signature (Delta(33)S =+3.3 parts per thousand). This reflects the secondary mineralization of remobilized sedimentary S carrying a component modified by photochemical reactions in the early Archaean atmosphere. It further represents one of the most extreme positive excursions so far known from the early Archaean rock record. Sulphides from a quartz-pyroxene rock and an ultramafic boudin from the island of Akilia, in the Godth (a) over circle bsfjord, have heterogeneous and generally radiogenic Pb isotopic compositions that we interpret to represent partial re-equilibration of Pb between the sulphides and whole rocks during tectonothermal events at 3.6, 2.7 and 1.6 Ga. Both these samples have Delta(33)S=0 (within analytical error) and therefore show no evidence for MIF sulphur. These data are consistent with previous interpretations that the rock cannot be proven to have a sedimentary origin. Our study illustrates that SIMS S-isotope measurements in ancient rocks can be used to elucidate early atmospheric parameters because of the ability to obtain combined S and Pb-isotope data, but caution must be applied when using such data to infer protolith. When information from geological context, petrography and chronology (i.e. by Pb isotopes) is combined and fully evaluated, Delta(33)S signatures from sulphides and their geological significance can be interpreted with a higher degree of confidence. (c) 2005 Elsevier B.V All rights reserved. Article in Journal/Newspaper Greenland Queensland University of Technology: QUT ePrints Greenland Chemical Geology 222 1-2 112 131 |
institution |
Open Polar |
collection |
Queensland University of Technology: QUT ePrints |
op_collection_id |
ftqueensland |
language |
unknown |
topic |
secondary ion mass spectrometer Pb isotopes S isotopes Archaean Greenland southern west greenland isua greenstone-belt itsaq gneiss complex earths earliest life crustal evolution microprobe analysis supracrustal belt amitsoq gneisses terrestrial lead ion-microprobe Geochemistry & Geophysics |
spellingShingle |
secondary ion mass spectrometer Pb isotopes S isotopes Archaean Greenland southern west greenland isua greenstone-belt itsaq gneiss complex earths earliest life crustal evolution microprobe analysis supracrustal belt amitsoq gneisses terrestrial lead ion-microprobe Geochemistry & Geophysics Whitehouse, M. J. Kamber, B. S. Fedo, C. M. Lepland, A. Integrated Pb- and S-isotope investigation of sulphide minerals from the early Archaean of southwest Greenland |
topic_facet |
secondary ion mass spectrometer Pb isotopes S isotopes Archaean Greenland southern west greenland isua greenstone-belt itsaq gneiss complex earths earliest life crustal evolution microprobe analysis supracrustal belt amitsoq gneisses terrestrial lead ion-microprobe Geochemistry & Geophysics |
description |
We present high-spatial resolution secondary ion mass spectrometry (SIMS) measurements of Pb and S isotopes in sulphides from early Archaean samples at two localities in southwest Greenland. Secondary pyrite from a 3.71 Ga sample of magnetite-quartz banded iron formation in the Isua Greenstone Belt, which has previously yielded unradiogenic Pb consistent with its ancient origin, contains sulphur with a mass independently fractionated (MIF) isotope signature (Delta(33)S =+3.3 parts per thousand). This reflects the secondary mineralization of remobilized sedimentary S carrying a component modified by photochemical reactions in the early Archaean atmosphere. It further represents one of the most extreme positive excursions so far known from the early Archaean rock record. Sulphides from a quartz-pyroxene rock and an ultramafic boudin from the island of Akilia, in the Godth (a) over circle bsfjord, have heterogeneous and generally radiogenic Pb isotopic compositions that we interpret to represent partial re-equilibration of Pb between the sulphides and whole rocks during tectonothermal events at 3.6, 2.7 and 1.6 Ga. Both these samples have Delta(33)S=0 (within analytical error) and therefore show no evidence for MIF sulphur. These data are consistent with previous interpretations that the rock cannot be proven to have a sedimentary origin. Our study illustrates that SIMS S-isotope measurements in ancient rocks can be used to elucidate early atmospheric parameters because of the ability to obtain combined S and Pb-isotope data, but caution must be applied when using such data to infer protolith. When information from geological context, petrography and chronology (i.e. by Pb isotopes) is combined and fully evaluated, Delta(33)S signatures from sulphides and their geological significance can be interpreted with a higher degree of confidence. (c) 2005 Elsevier B.V All rights reserved. |
format |
Article in Journal/Newspaper |
author |
Whitehouse, M. J. Kamber, B. S. Fedo, C. M. Lepland, A. |
author_facet |
Whitehouse, M. J. Kamber, B. S. Fedo, C. M. Lepland, A. |
author_sort |
Whitehouse, M. J. |
title |
Integrated Pb- and S-isotope investigation of sulphide minerals from the early Archaean of southwest Greenland |
title_short |
Integrated Pb- and S-isotope investigation of sulphide minerals from the early Archaean of southwest Greenland |
title_full |
Integrated Pb- and S-isotope investigation of sulphide minerals from the early Archaean of southwest Greenland |
title_fullStr |
Integrated Pb- and S-isotope investigation of sulphide minerals from the early Archaean of southwest Greenland |
title_full_unstemmed |
Integrated Pb- and S-isotope investigation of sulphide minerals from the early Archaean of southwest Greenland |
title_sort |
integrated pb- and s-isotope investigation of sulphide minerals from the early archaean of southwest greenland |
publisher |
Elsevier |
publishDate |
2005 |
url |
https://eprints.qut.edu.au/126251/ |
geographic |
Greenland |
geographic_facet |
Greenland |
genre |
Greenland |
genre_facet |
Greenland |
op_source |
Chemical Geology |
op_relation |
doi:10.1016/j.chemgeo.2005.06.004 Whitehouse, M. J., Kamber, B. S., Fedo, C. M., & Lepland, A. (2005) Integrated Pb- and S-isotope investigation of sulphide minerals from the early Archaean of southwest Greenland. Chemical Geology, 222(1-2), pp. 112-131. https://eprints.qut.edu.au/126251/ Science & Engineering Faculty; Australian Research Centre for Aerospace Automation |
op_rights |
Consult author(s) regarding copyright matters This work is covered by copyright. Unless the document is being made available under a Creative Commons Licence, you must assume that re-use is limited to personal use and that permission from the copyright owner must be obtained for all other uses. If the document is available under a Creative Commons License (or other specified license) then refer to the Licence for details of permitted re-use. It is a condition of access that users recognise and abide by the legal requirements associated with these rights. If you believe that this work infringes copyright please provide details by email to qut.copyright@qut.edu.au |
op_doi |
https://doi.org/10.1016/j.chemgeo.2005.06.004 |
container_title |
Chemical Geology |
container_volume |
222 |
container_issue |
1-2 |
container_start_page |
112 |
op_container_end_page |
131 |
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1798846651718172672 |