2024-03-29T14:11:46Zhttp://digital.csic.es/dspace-oai/requestoai:digital.csic.es:10261/296972016-02-17T05:00:13Zcom_10261_83com_10261_8com_10261_262578col_10261_336col_10261_262579
New findings of trilobites and graptolites in the Ordovician of Bulgaria
Novi nahodki na trilobiti i graptoliti v ordovika na Bulgaria
Gutiérrez-Marco, J. C.
Yanev, Slavcho N.
Sachanski, Valeri V.
Rábano Gutiérrez del Arroyo, Isabel
Lakova, Iskra
Ordovician
Bulgaria
Trilobites
Graptolites
Biostratigraphy
Correlation
Gondwana
8 páginas, 2 figuras, 1 lámina.
Darriwilian trilobites and graptolites from the Grohoten Formation (Svoge anticliorium, Sofia Stara Planina
Mountain) are reviewed in the light of the new records and by direct examination of the original material reported by previous
authors between 1934 and 1958 years. Middle Ordovician fossils are distributed in three stratigraphically successive assemblages.
The oldest one derives from Lower Oretanian shales with nodules and consists of pendent and extensiform
didymograptids (Didymograptus cf. artus, D. cf. spinulosus, D. s.l. ferrugineus), some biserials (Haddingograptus ?), a single
benthic atheloptic trilobite (Placoparia balcanica n. sp.), and probably also of rare pelagic form Cyclopyge cf. kossleri. The
middle assemblage which is dominated by pelagic trilobites such as Pricyclopyge binodosa binodosa, R binodosa prisca and
Microparia sp., and sparse benthic elements (Ectillaenus sp.), is recorded from siltstones and silty shales that directly overlie a
variously developed middle, quartzitic member. The presence both of the graptolite Didymograptus murchisoni and the rare
biserial forms confirm an Upper Oretanian age for the association. Finally, the third and youngest Middle Ordovician
palaeontological horizon is characterized by the occurence of the Dobrotivian cyclopygid trilobite Pricyclopyge binodosa
longicephala, which derives from the settled shales and is located well below the latest assemblage of trilobites and brachiopods
already of Berounian (Upper Ordovician) age. Closest comparisons of the Bulgarian trilobites are with the cyclopygid biofacies
from the deep outer shelf settings of the peri-Gondwanan platform, shown by the record of some typical Bohemian taxa as P. binodosa prisca and P. binodosa longicephala.
Proyectos: Nº 2001BG0005, 2001-2002. 602/1996 y 410 de PIGS (IUGS-UNESCO).
Peer reviewed
2010-12-01T09:19:01Z
2010-12-01T09:19:01Z
2002
artículo
http://purl.org/coar/resource_type/c_6501
Review of the Bulgarian Geological Society 63(1-3): 51-58 (2002)
0007-3938
http://hdl.handle.net/10261/29697
otro
http://www.bgd.bg/REVIEW_BGS/frames_home_EN.html
open
Bulgarian Academy of Sciences