Application of carbon isotope chemostratigraphy to the Renison dolomites, Tasmania: a Neoproterozoic age
This study uses carbon isotope chemostratigraphy to propose an age for the Success Creek Group and Crimson Creek Formation in the absence of any direct radiometric dates, palaeomagnetic or reliable palaeontological data. The 13C values were determined for the least-altered dolomite samples. Suitable...
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ftunivtasecite:oai:ecite.utas.edu.au:12138 2023-05-15T18:42:38+02:00 Application of carbon isotope chemostratigraphy to the Renison dolomites, Tasmania: a Neoproterozoic age Adabi, MH 1997 https://doi.org/10.1080/08120099708728353 http://ecite.utas.edu.au/12138 en eng Blackwell http://dx.doi.org/10.1080/08120099708728353 Adabi, MH, Application of carbon isotope chemostratigraphy to the Renison dolomites, Tasmania: a Neoproterozoic age, Australian Journal of Earth Sciences, 44, (6) pp. 767-775. ISSN 0812-0099 (1997) [Refereed Article] http://ecite.utas.edu.au/12138 Earth Sciences Geochemistry Geochemistry not elsewhere classified Refereed Article PeerReviewed 1997 ftunivtasecite https://doi.org/10.1080/08120099708728353 2019-12-13T20:57:04Z This study uses carbon isotope chemostratigraphy to propose an age for the Success Creek Group and Crimson Creek Formation in the absence of any direct radiometric dates, palaeomagnetic or reliable palaeontological data. The 13C values were determined for the least-altered dolomite samples. Suitable samples were selected on the basis of grainsize, cathodoluminescence petrography, most enriched 18O values ( > -2) low Mn/Sr ratios and low Fe and Mn concentrations. The average least-altered, most 13C-enriched dolomicrite samples in the youngest (No. 1) dolomite horizon are + 4.6. This is typical of Neoproterozoic (but not Cambrian) carbonates. The 13C values of all dolomite samples in the succession are significantly positive (up to + 7.5) and the excursion characteristic of the Proterozoic/Cambrian boundary has not been observed. The lack of negative 13C values in all dolomite samples studied also suggests an absence of correlatives of Sturtian and Varanger tillites in the dolomite successions. The 13C values in all three dolomite horizons suggest a Neoproterozoic age between about 820 to 570 Ma (Cryogenian to Neoproterozoic III) on the current global compilation carbon isotope curves. This age for the Success Creek Group and Crimson Creek Formation, inferred from carbon isotope chemostratigraphy, can be substantiated by other evidence. The age of the Renison dolomites is constrained by K-Ar dates of 708 6 Ma from detrital muscovite in the underlying Oonah Formation and 588 8 and 600 8 Ma from doleritic rock in a lithostratigraphic equivalent of the Crimson Creek Formation from the Smithton Basin. Furthermore, acritarchs and the stromatolite Baicalia cf. B. burra also suggest a Neoproterozoic rather than Cambrian age. Article in Journal/Newspaper Varanger eCite UTAS (University of Tasmania) Renison ENVELOPE(-81.116,-81.116,50.967,50.967) Australian Journal of Earth Sciences 44 6 767 775 |
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Open Polar |
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eCite UTAS (University of Tasmania) |
op_collection_id |
ftunivtasecite |
language |
English |
topic |
Earth Sciences Geochemistry Geochemistry not elsewhere classified |
spellingShingle |
Earth Sciences Geochemistry Geochemistry not elsewhere classified Adabi, MH Application of carbon isotope chemostratigraphy to the Renison dolomites, Tasmania: a Neoproterozoic age |
topic_facet |
Earth Sciences Geochemistry Geochemistry not elsewhere classified |
description |
This study uses carbon isotope chemostratigraphy to propose an age for the Success Creek Group and Crimson Creek Formation in the absence of any direct radiometric dates, palaeomagnetic or reliable palaeontological data. The 13C values were determined for the least-altered dolomite samples. Suitable samples were selected on the basis of grainsize, cathodoluminescence petrography, most enriched 18O values ( > -2) low Mn/Sr ratios and low Fe and Mn concentrations. The average least-altered, most 13C-enriched dolomicrite samples in the youngest (No. 1) dolomite horizon are + 4.6. This is typical of Neoproterozoic (but not Cambrian) carbonates. The 13C values of all dolomite samples in the succession are significantly positive (up to + 7.5) and the excursion characteristic of the Proterozoic/Cambrian boundary has not been observed. The lack of negative 13C values in all dolomite samples studied also suggests an absence of correlatives of Sturtian and Varanger tillites in the dolomite successions. The 13C values in all three dolomite horizons suggest a Neoproterozoic age between about 820 to 570 Ma (Cryogenian to Neoproterozoic III) on the current global compilation carbon isotope curves. This age for the Success Creek Group and Crimson Creek Formation, inferred from carbon isotope chemostratigraphy, can be substantiated by other evidence. The age of the Renison dolomites is constrained by K-Ar dates of 708 6 Ma from detrital muscovite in the underlying Oonah Formation and 588 8 and 600 8 Ma from doleritic rock in a lithostratigraphic equivalent of the Crimson Creek Formation from the Smithton Basin. Furthermore, acritarchs and the stromatolite Baicalia cf. B. burra also suggest a Neoproterozoic rather than Cambrian age. |
format |
Article in Journal/Newspaper |
author |
Adabi, MH |
author_facet |
Adabi, MH |
author_sort |
Adabi, MH |
title |
Application of carbon isotope chemostratigraphy to the Renison dolomites, Tasmania: a Neoproterozoic age |
title_short |
Application of carbon isotope chemostratigraphy to the Renison dolomites, Tasmania: a Neoproterozoic age |
title_full |
Application of carbon isotope chemostratigraphy to the Renison dolomites, Tasmania: a Neoproterozoic age |
title_fullStr |
Application of carbon isotope chemostratigraphy to the Renison dolomites, Tasmania: a Neoproterozoic age |
title_full_unstemmed |
Application of carbon isotope chemostratigraphy to the Renison dolomites, Tasmania: a Neoproterozoic age |
title_sort |
application of carbon isotope chemostratigraphy to the renison dolomites, tasmania: a neoproterozoic age |
publisher |
Blackwell |
publishDate |
1997 |
url |
https://doi.org/10.1080/08120099708728353 http://ecite.utas.edu.au/12138 |
long_lat |
ENVELOPE(-81.116,-81.116,50.967,50.967) |
geographic |
Renison |
geographic_facet |
Renison |
genre |
Varanger |
genre_facet |
Varanger |
op_relation |
http://dx.doi.org/10.1080/08120099708728353 Adabi, MH, Application of carbon isotope chemostratigraphy to the Renison dolomites, Tasmania: a Neoproterozoic age, Australian Journal of Earth Sciences, 44, (6) pp. 767-775. ISSN 0812-0099 (1997) [Refereed Article] http://ecite.utas.edu.au/12138 |
op_doi |
https://doi.org/10.1080/08120099708728353 |
container_title |
Australian Journal of Earth Sciences |
container_volume |
44 |
container_issue |
6 |
container_start_page |
767 |
op_container_end_page |
775 |
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1766232364440092672 |