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Fossil floral assemblage from the Upper Triassic Grabowa Formation (Upper Silesia, southern Poland)165–193165–193

Wawrzyniak Zuzanna, Filipiak Paweł

Annales Societatis Geologorum Poloniae

2023

Vol. 93, No. 2

165--193

Upper Triassic fossil plants are well documented from the Keuper of Europe. Carnian and Rhaetian floras are rich in a variety of plant taxa, whereas in comparison, the Norian is limited to a few localities with poorly preserved fossil plant communities showing low diversification. The Norian Grabowa Formation in Zawiercie-Marciszów, Upper Silesia, southern Poland, contains fossils of arborescent gymnosperms, including petrified conifer trunks. In this study, we present a fossil plant assemblage, containing fragmented plant parts in multiple forms of preservation, i.e., permineralised trunks and rooting structures, stems compressions, dispersed cuticles, and megaspores. Analysis of the macromorphological characters proved the presence of gymnosperms, including the ar-borescent conifer Agathoxylon cf. keuperianum, known already from this locality from fragments of charcoalified wood. Sphenophytes are represented by disarticulated stems of Equisetites sp., and Neocalamites sp. The variation in plant fossils indicates the possibility of higher plant diversity. Analysis of cuticles, macerated from different plant-bearing lithologies, revealed a variety of conifer foliage, expressed as five cuticulae dispersae morphotypes (needle-leaf Elatocladus-type and scale-leaf Pagio- Brachyphyllum-like). Plant fossils at Zawiercie-Marciszów are preserved in calcareous mudstones and micritic limestone concretions, developed in a fluvial environment. The presence of sphenophyte stems (Equisetites and Neocalamites) indicates that local conditions were more humid and suitable for spore-producing plants, appearing in the mid-Norian tectonic-pluvial episode, recorded in the Grabowa Fm.

The pre-Taghanic (Givetian, Middle Devonian) ecosystems of Miłoszów (Holy Cross Mts, Poland)

Halamski Adam T., Baliński Andrzej, Racki Grzegorz, Amler Michael R. W., Basse Martin, Denayer Julien, Dubicka Zofia, Filipiak Paweł, Kondas Marcelina, Krawczyński Wojciech, Mieszkowski Radosław, Narkiewicz Katarzyna, Olempska Ewa, Wrzołek Tomasz, Wyse-Jacson Patrick N., Zapalski Mikołaj K., Zatoń Michał, Kozłowski Wojciech

Annales Societatis Geologorum Poloniae

2022

Vol. 92, No. 4

323--379

The middle and upper parts of the Skały Fm, Early to Middle Givetian in age, were investigated in four sections at Miłoszów Wood in the Łysogóry Region (northern region of the Holy Cross Mountains, central Poland). The dating is based on conodonts (Polygnathus timorensis Zone to the later part of the Polygnathus varcus/Polygnathus rhenanus Zone; early Polygnathus ansatus Zone cannot be excluded) and spores (Ex1–2 subzones) and, coupled with cartographic analysis and geophysical investigation, allows correlation within the strongly faulted succession. Significant lateral facies variations within the carbonate ramp depositional system in comparison with the better studied Grzegorzowice–Skały section, about 3 km distant, are documented, thanks to conodont-based correlation of both successions. Foraminifers, fungi, sponges, rugose and tabulate corals, medusozoans, microconchids and cornulitids, polychaetes (scolecodonts), molluscs (bivalves, rostroconchs, and gastropods), arthropods (trilobites and ostracods), bryozoans, hederelloids, ascodictyids, brachiopods, echinoderms (mostly crinoids, rare echinoids, holuthurians, and ophiocistoids), conodonts, fish, plants (prasinophytes, chlorophycophytes, and land plant spores), and acritarchs are present. Brachiopods are the most diverse phylum present (68 species), other richly represented groups are bryozoans and echinoderms; in contrast, cephalopods and trilobites are low in diversity and abundance. The muddy, middle to outer ramp biota (200 marine taxa, including 170 species of marine animals, 22 photoautotrophs, 6 forams) represents a mixture of allochthonous shallower-water communities (upper BA3), including storm- and possibly tsunami-affected coral mounds, and autochthonous deep-water soft-bottom brachiopod (e.g., Bifida–Echinocoelia) communities (BA 4–5). The richness and diversity of the Miłoszów biota is relatively high, comparable with other approximately coeval pre-Taghanic ecosystems during the Devonian climatic deterioration (cooling). Preliminary data indicate that in the Holy Cross Mountains, no large-scale replacement of brachiopod (and probably many other benthic ones, like crinoids) communities took place between the Early–Middle Givetian and the Early Frasnian, in contrast to the demise of the Hamilton/Upper Tully fauna in the Appalachian Basin. Such a similarity of pre- and post-Taghanic faunas does not exclude the occurrence of environmental perturbations and transient community turnovers, caused by immigrations during the Taghanic Biocrisis, but evidences the successful recovery of the indigenous biota.

Sedimentary environments and stratigraphy of the Stipinai Formation (Upper Frasnian, northern Lithuania) : a sedimentary record of sea-level changes in the Main Devonian Field of the East European Platform

Jaglarz Piotr, Rychliński Tomasz, Filipiak Paweł, Uchman Alfred, Vainorius Julius

Geological Quarterly

2021

Vol. 65, No. 4

art. no. 52

The Frasnian carbonate-siliciclastic deposits of the Stipinai Formation exposed in two quarries at Petrašiūnai and Klovainiai (northern Lithuania) show considerable vertical facies changes. The lower part of this succession is dominated by argillaceous dolomitic facies with subordinate fine siliciclastic deposits. They display haloturbation and bioturbation structures, represent a hypersaline lagoonal environment, and record the beginning of the transgression. The middle part of the succession consists of secondary dolostones containing moulds of brachiopods, tetracorals, stromatoporoids and trace fossils of deposit feeders; these were deposited in a shallow subtidal marine environment and represent the deepest sedimentary environment of this succession. This was followed by a lagoonal environment (episodic hypersaline), represented by dolomudstones and marly dolomudstones. The upper part of the succession is built of bedded dolostones which document a shallowing trend. Intercalations of clays and palaeosol horizons record emergence events. Palynostratigraphic data tentatively indicate that the Stipinai Formation represents the Upper Frasnian. The succession can be interpreted as a record of the upper part of a T-R cycle (related to the semichatovae transgression) in the Main Devonian Field of the East European Platform. The Stipinai Formation is distributed across western and central Latvia and has a correlative in the Pomerania Basin (northern Poland).