U–Pb age constraints on the Carboniferous–Permian transition in continental basins of eastern equatorial Pangaea (France): implications for the depositional history and correlations across the late Variscan Belt
Mathilde Mercuzot, Camille Rossignol, Sylvie Bourquin, Jahandar Ramezani, Céline Ducassou, Marc Poujol, Laurent Beccaletto, Pierre Pellenard
{"title":"U–Pb age constraints on the Carboniferous–Permian transition in continental basins of eastern equatorial Pangaea (France): implications for the depositional history and correlations across the late Variscan Belt","authors":"Mathilde Mercuzot, Camille Rossignol, Sylvie Bourquin, Jahandar Ramezani, Céline Ducassou, Marc Poujol, Laurent Beccaletto, Pierre Pellenard","doi":"10.1144/jgs2023-075","DOIUrl":null,"url":null,"abstract":"Intramontane late Carboniferous–Permian basins of western Europe developed during the latest orogenic stages of the Variscan Mountain Belt in eastern Pangaea, at equatorial palaeolatitudes. Their stratigraphic framework is mainly based on continental subdivisions (e.g. Stephanian and Autunian continental stages), which can be contentious owing to biostratigraphic biases, resulting in long-distance diachronous subdivisions. To provide precise inter-basinal and global correlations to the internationally recognized chronostratigraphic marine stages, this study reports new U–Pb geochronology from the Aumance and Decize–La Machine basins, located in the northern French Massif Central. Zircon grains extracted from three volcanic ash-fall layers give weighted mean 206 Pb/ 238 U ages of 299.11 ± 0.35, 298.73 ± 0.36 and 298.59 ± 0.35 Ma (2 <mml:math xmlns:mml=\"http://www.w3.org/1998/Math/MathML\" overflow=\"scroll\"> <mml:mi>σ</mml:mi> </mml:math> total propagated uncertainty) by the chemical abrasion isotope dilution thermal ionization mass spectrometry method, coinciding with the Carboniferous–Permian transition (Gzhelian and Asselian stages). These ages imply that the northern Massif Central basins developed synchronously in relatively short periods of time (<10 myr), reflecting substantial sedimentation rates. Finally, the new chronology of infilling of these basins confirms that they were connected during the late Carboniferous and early Permian periods, improving the knowledge on the late orogenic Variscan geodynamic setting in this area. Supplementary material: Operating conditions and complete analytical results are available at https://doi.org/10.6084/m9.figshare.c.6805228","PeriodicalId":17320,"journal":{"name":"Journal of the Geological Society","volume":null,"pages":null},"PeriodicalIF":2.6000,"publicationDate":"2023-10-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of the Geological Society","FirstCategoryId":"1085","ListUrlMain":"https://doi.org/10.1144/jgs2023-075","RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"GEOSCIENCES, MULTIDISCIPLINARY","Score":null,"Total":0}
引用次数: 0
Abstract
Intramontane late Carboniferous–Permian basins of western Europe developed during the latest orogenic stages of the Variscan Mountain Belt in eastern Pangaea, at equatorial palaeolatitudes. Their stratigraphic framework is mainly based on continental subdivisions (e.g. Stephanian and Autunian continental stages), which can be contentious owing to biostratigraphic biases, resulting in long-distance diachronous subdivisions. To provide precise inter-basinal and global correlations to the internationally recognized chronostratigraphic marine stages, this study reports new U–Pb geochronology from the Aumance and Decize–La Machine basins, located in the northern French Massif Central. Zircon grains extracted from three volcanic ash-fall layers give weighted mean 206 Pb/ 238 U ages of 299.11 ± 0.35, 298.73 ± 0.36 and 298.59 ± 0.35 Ma (2 σ total propagated uncertainty) by the chemical abrasion isotope dilution thermal ionization mass spectrometry method, coinciding with the Carboniferous–Permian transition (Gzhelian and Asselian stages). These ages imply that the northern Massif Central basins developed synchronously in relatively short periods of time (<10 myr), reflecting substantial sedimentation rates. Finally, the new chronology of infilling of these basins confirms that they were connected during the late Carboniferous and early Permian periods, improving the knowledge on the late orogenic Variscan geodynamic setting in this area. Supplementary material: Operating conditions and complete analytical results are available at https://doi.org/10.6084/m9.figshare.c.6805228
期刊介绍:
Journal of the Geological Society (JGS) is owned and published by the Geological Society of London.
JGS publishes topical, high-quality recent research across the full range of Earth Sciences. Papers are interdisciplinary in nature and emphasize the development of an understanding of fundamental geological processes. Broad interest articles that refer to regional studies, but which extend beyond their geographical context are also welcomed.
Each year JGS presents the ‘JGS Early Career Award'' for papers published in the journal, which rewards the writing of well-written, exciting papers from early career geologists.
The journal publishes research and invited review articles, discussion papers and thematic sets.