Oxygen isotope variability in conodonts: implications for reconstructing Palaeozoic palaeoclimates and palaeoceanography
Conodonts have the potential to elucidate the intricacies of Palaeozoic climates, especially if δ 18O values of single apatitic tooth-like 'elements' can be used to map evolving sea surface temperatures and differentiate oceanic water masses. Their ecological distribution as pelagic and ne...
| Những tác giả chính: | , , |
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| Định dạng: | Journal article |
| Ngôn ngữ: | English |
| Được phát hành: |
2012
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| _version_ | 1826266387943784448 |
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| author | Wheeley, JR Smith, M Boomer, I |
| author_facet | Wheeley, JR Smith, M Boomer, I |
| author_sort | Wheeley, JR |
| collection | OXFORD |
| description | Conodonts have the potential to elucidate the intricacies of Palaeozoic climates, especially if δ 18O values of single apatitic tooth-like 'elements' can be used to map evolving sea surface temperatures and differentiate oceanic water masses. Their ecological distribution as pelagic and nektobenthic organisms, high-resolution biostratigraphy, and abundance in Cambrian-Triassic rocks qualifies them as potentially robust climate archives. Previous ion microprobe conodont δ 18O studies have proceeded directly to palaeotempera-ture interpretation without appreciation of inter- and intra-element variability or post-mortem artefacts. Here, ion microprobe analyses of Ordovician and Silurian conodonts establishes that: intra-element crown tissue δ 18O typically varies by <1%o (53% of conodonts analysed), is normally <2%o (92% of analyses), and rarely varies by 2-4%o; δ 18O can vary across elements, suggesting a microstructural and/or diagenetic control; δ 18O can vary between species representatives by c. 3%o; δ 18O of pelagic and nektobenthic taxa can be offset by 2-3%o; elements processed with formic acid have highly variable δ 18O; and thermal alteration does affect δ 18O. Conodont ion microprobe δ 18O values are comparable with those of bulk methods, but utilization of material with no consideration of geological context or processing history may introduce significant artefacts. A protocol for future conodont oxygen isotope ion microprobe studies is proposed. |
| first_indexed | 2024-03-06T20:38:09Z |
| format | Journal article |
| id | oxford-uuid:3353b99f-ad7c-43d9-a53b-9d26db9c22b9 |
| institution | University of Oxford |
| language | English |
| last_indexed | 2024-03-06T20:38:09Z |
| publishDate | 2012 |
| record_format | dspace |
| spelling | oxford-uuid:3353b99f-ad7c-43d9-a53b-9d26db9c22b92022-03-26T13:19:37ZOxygen isotope variability in conodonts: implications for reconstructing Palaeozoic palaeoclimates and palaeoceanographyJournal articlehttp://purl.org/coar/resource_type/c_dcae04bcuuid:3353b99f-ad7c-43d9-a53b-9d26db9c22b9EnglishSymplectic Elements at Oxford2012Wheeley, JRSmith, MBoomer, IConodonts have the potential to elucidate the intricacies of Palaeozoic climates, especially if δ 18O values of single apatitic tooth-like 'elements' can be used to map evolving sea surface temperatures and differentiate oceanic water masses. Their ecological distribution as pelagic and nektobenthic organisms, high-resolution biostratigraphy, and abundance in Cambrian-Triassic rocks qualifies them as potentially robust climate archives. Previous ion microprobe conodont δ 18O studies have proceeded directly to palaeotempera-ture interpretation without appreciation of inter- and intra-element variability or post-mortem artefacts. Here, ion microprobe analyses of Ordovician and Silurian conodonts establishes that: intra-element crown tissue δ 18O typically varies by <1%o (53% of conodonts analysed), is normally <2%o (92% of analyses), and rarely varies by 2-4%o; δ 18O can vary across elements, suggesting a microstructural and/or diagenetic control; δ 18O can vary between species representatives by c. 3%o; δ 18O of pelagic and nektobenthic taxa can be offset by 2-3%o; elements processed with formic acid have highly variable δ 18O; and thermal alteration does affect δ 18O. Conodont ion microprobe δ 18O values are comparable with those of bulk methods, but utilization of material with no consideration of geological context or processing history may introduce significant artefacts. A protocol for future conodont oxygen isotope ion microprobe studies is proposed. |
| spellingShingle | Wheeley, JR Smith, M Boomer, I Oxygen isotope variability in conodonts: implications for reconstructing Palaeozoic palaeoclimates and palaeoceanography |
| title | Oxygen isotope variability in conodonts: implications for reconstructing Palaeozoic palaeoclimates and palaeoceanography |
| title_full | Oxygen isotope variability in conodonts: implications for reconstructing Palaeozoic palaeoclimates and palaeoceanography |
| title_fullStr | Oxygen isotope variability in conodonts: implications for reconstructing Palaeozoic palaeoclimates and palaeoceanography |
| title_full_unstemmed | Oxygen isotope variability in conodonts: implications for reconstructing Palaeozoic palaeoclimates and palaeoceanography |
| title_short | Oxygen isotope variability in conodonts: implications for reconstructing Palaeozoic palaeoclimates and palaeoceanography |
| title_sort | oxygen isotope variability in conodonts implications for reconstructing palaeozoic palaeoclimates and palaeoceanography |
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