Number of the records: 1
A graptolite-rich Ordovician-Silurian boundary section in the south-central Pyrenees, Spain: stratigraphical and palaeobiogeographical significance
- 1.
SYSNO ASEP 0505046 Document Type J - Journal Article R&D Document Type Journal Article Subsidiary J Článek ve WOS Title A graptolite-rich Ordovician-Silurian boundary section in the south-central Pyrenees, Spain: stratigraphical and palaeobiogeographical significance Author(s) Štorch, Petr (GLU-S) RID, SAI, ORCID
Bernal, J. R. (ES)
Gutiérrez-Marco, J. C. (ES)Source Title Geological Magazine. - : Cambridge University Press - ISSN 0016-7568
Roč. 156, č. 6 (2019), s. 1069-1091Number of pages 23 s. Publication form Print - P Language eng - English Country GB - United Kingdom Keywords Ordovician-Silurian boundary ; graptolites ; biostratigraphy ; carbon isotopes ; abnormal astogeny Subject RIV DB - Geology ; Mineralogy OECD category Paleontology R&D Projects GA14-16124S GA ČR - Czech Science Foundation (CSF) Method of publishing Limited access Institutional support GLU-S - RVO:67985831 UT WOS 000466534300008 EID SCOPUS 85049299871 DOI 10.1017/S001675681800047X Annotation An Ordovician-Silurian boundary section marked by an uninterrupted, relatively high rate of black shale sedimentation and abundant, diverse graptolites is described from the south-central Pyrenees. The structurally simple Estana section comprises the uppermost part of the quartzite-dominated Bar Formation and overlying black shales of late Hirnantian and early Rhuddanian age, which have been dated by graptolites to the upper Metabolograptus. persculptus and lower-middle Akidograptus ascensus-Parakidograptus acuminatus biozones. Due to the absence of M. persculptus, a Metabolograptus parvulus Biozone correlative with the upper part of the persculptus Biozone is recognized below the lowest occurrence of akidograptids, which indicate the base of the Silurian System. The graptolite fauna comprise 27 species including Normalograptus minor, N. lubricus, N. rhizinus, Hirsutograptus, Korenograptus bifurcus, K. bicaudatus, K. lanpherei and Nd. shanchongensis, most of which were formerly considered to be endemic to the low-latitude palaeobiogeographical province of China, Siberia and northern North America. Two new species, N. baridaensis and N. ednae, are described. The succession of graptolite assemblages in the Estana section, and occurrence of several cosmopolitan taxa in its parvulus and lower ascensus-acuminatus biozones that are unknown elsewhere in peri-Gondwanan Europe, suggest that strata immediately surrounding the Ordovician-Silurian boundary may be absent, highly condensed or oxic and barren of graptolites in other sections of northwestern peri-Gondwana. Common graptolite synrhabdosomes and abnormal rhabdosomes may indicate some environmental stress in the parvulus Biozone, although the rather uniform black shale lithology, total organic carbon content and δ13 Corg values suggest uninterrupted sedimentation under stable, anoxic conditions. Workplace Institute of Geology Contact Jana Popelková, popelkova@gli.cas.cz, Sabina Janíčková, Tel.: 233 087 272 Year of Publishing 2020 Electronic address https://www.cambridge.org/core/journals/geological-magazine/article/graptoliterich-ordoviciansilurian-boundary-section-in-the-southcentral-pyrenees-spain-stratigraphical-and-palaeobiogeographical-significance/33F3604EAF424E10CE9524DA56AEE217
Number of the records: 1