Latest Ordovician age of the Spinachitina fragilis Chitinozoan Biozone in Baltoscandia
The global Spinachitina fragilis Chitinozoan Biozone has been considered the lowermost Silurian zone in most publications. S. fragilis was first described from the Ohesaare drill core, Estonia, and utilised as a Baltic regional zonal taxon together with Ancyrochitina laevaensis. Despite its wide geo...
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| Format: | Article |
| Language: | English |
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Estonian Academy Publishers
2023-06-01
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| Series: | Estonian Journal of Earth Sciences |
| Subjects: | |
| Online Access: | https://kirj.ee/wp-content/plugins/kirj/pub/earth-1-2023-82-85_20230610104516.pdf |
| _version_ | 1797804397040762880 |
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| author | Jaak Nõlvak Yan Liang Olle Hints |
| author_facet | Jaak Nõlvak Yan Liang Olle Hints |
| author_sort | Jaak Nõlvak |
| collection | DOAJ |
| description | The global Spinachitina fragilis Chitinozoan Biozone has been considered the lowermost Silurian zone in most publications. S. fragilis was first described from the Ohesaare drill core, Estonia, and utilised as a Baltic regional zonal taxon together with Ancyrochitina laevaensis. Despite its wide geographical occurrence, S. fragilishas remained poorly documented in its type region. This has created confusion in taxonomy and distribution of the species. Herein, we have restudied material from the type locality and supplementary sections in the East Baltic region. S. fragilis generally has a very short stratigraphic range, which, according to new data on carbon isotope chemostratigraphy, coincides with the falling limb of the Hirnantian carbon isotope excursion. This suggests the latest Hirnantian rather than the early Rhuddanian age of the Spinachitina fragilis Chitinozoan Biozone in Baltoscandia. Based on this view, we revise the latest Ordovician chitinozoan biozonal scheme for the region. Globally, the S. fragilis Biozone may span across the OrdovicianâSilurian boundary. |
| first_indexed | 2024-03-13T05:35:29Z |
| format | Article |
| id | doaj.art-672511aa85214ae98814e8dadc87c3f1 |
| institution | Directory Open Access Journal |
| issn | 1736-4728 1736-7557 |
| language | English |
| last_indexed | 2024-03-13T05:35:29Z |
| publishDate | 2023-06-01 |
| publisher | Estonian Academy Publishers |
| record_format | Article |
| series | Estonian Journal of Earth Sciences |
| spelling | doaj.art-672511aa85214ae98814e8dadc87c3f12023-06-14T07:33:30ZengEstonian Academy PublishersEstonian Journal of Earth Sciences1736-47281736-75572023-06-017218285https://doi.org/10.3176/earth.2023.51https://doi.org/10.3176/earth.2023.51Latest Ordovician age of the Spinachitina fragilis Chitinozoan Biozone in BaltoscandiaJaak Nõlvak0Yan Liang1Olle Hints2Department of Geology, School of Science, Tallinn University of Technology, Ehitajate tee 5, 19086 Tallinn, Estonia; jaak.nolvak@ttu.eeState Key Laboratory of Palaeobiology and Stratigraphy, Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences, Nanjing 210008, ChinaDepartment of Geology, School of Science, Tallinn University of Technology, Ehitajate tee 5, 19086 Tallinn, Estonia; olle.hints@taltech.eeThe global Spinachitina fragilis Chitinozoan Biozone has been considered the lowermost Silurian zone in most publications. S. fragilis was first described from the Ohesaare drill core, Estonia, and utilised as a Baltic regional zonal taxon together with Ancyrochitina laevaensis. Despite its wide geographical occurrence, S. fragilishas remained poorly documented in its type region. This has created confusion in taxonomy and distribution of the species. Herein, we have restudied material from the type locality and supplementary sections in the East Baltic region. S. fragilis generally has a very short stratigraphic range, which, according to new data on carbon isotope chemostratigraphy, coincides with the falling limb of the Hirnantian carbon isotope excursion. This suggests the latest Hirnantian rather than the early Rhuddanian age of the Spinachitina fragilis Chitinozoan Biozone in Baltoscandia. Based on this view, we revise the latest Ordovician chitinozoan biozonal scheme for the region. Globally, the S. fragilis Biozone may span across the OrdovicianâSilurian boundary.https://kirj.ee/wp-content/plugins/kirj/pub/earth-1-2023-82-85_20230610104516.pdfchitinozoansbiostratigraphyordovician–silurian boundary bedseast baltic |
| spellingShingle | Jaak Nõlvak Yan Liang Olle Hints Latest Ordovician age of the Spinachitina fragilis Chitinozoan Biozone in Baltoscandia Estonian Journal of Earth Sciences chitinozoans biostratigraphy ordovician–silurian boundary beds east baltic |
| title | Latest Ordovician age of the Spinachitina fragilis Chitinozoan Biozone in Baltoscandia |
| title_full | Latest Ordovician age of the Spinachitina fragilis Chitinozoan Biozone in Baltoscandia |
| title_fullStr | Latest Ordovician age of the Spinachitina fragilis Chitinozoan Biozone in Baltoscandia |
| title_full_unstemmed | Latest Ordovician age of the Spinachitina fragilis Chitinozoan Biozone in Baltoscandia |
| title_short | Latest Ordovician age of the Spinachitina fragilis Chitinozoan Biozone in Baltoscandia |
| title_sort | latest ordovician age of the spinachitina fragilis chitinozoan biozone in baltoscandia |
| topic | chitinozoans biostratigraphy ordovician–silurian boundary beds east baltic |
| url | https://kirj.ee/wp-content/plugins/kirj/pub/earth-1-2023-82-85_20230610104516.pdf |
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