کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
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4749928 | 1360625 | 2006 | 14 صفحه PDF | دانلود رایگان |
The study of Late Devonian Frasnian and Famennian conodonts in western Thailand confirms these species are mostly cosmopolitan. The Thailand section includes the Upper Kellwasser Event recorded in Europe, North America, China, and elsewhere, and probably also includes the upper part of the Lower Kellwasser Event. Stable isotope geochemistry for this interval shows a positive d13C excursion in the Late rhenana conodont Zone followed by a gradual return to normal, followed by a sudden positive excursion near the conodont extinction event. The latter has been chosen elsewhere as the Frasnian-Famennian boundary. The extinction event seems a consequence of unsteady conditions that could include eutrophic, oxygen, carbon dioxide, eustatic, and temperature fluctuations. There was a regional disappearance or extinction of several conodont species at the Frasnian-Famennian boundary followed by recovery and the spread of new species during the early Famennian.
Journal: Palaeoworld - Volume 15, Issue 2, May 2006, Pages 171–184