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Number of results: 4
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Abstract

Sparse fish microremains have been found in marine limestones from the Middle Devonian (Givetian) Skały

Formation (Sitka Coral-Crinoid Limestone Member and Sierżawy Member), Świętomarz–Śniadka section,

Bodzentyn Syncline, Łysogóry Region, northern Holy Cross Mountains, associated with conodonts of the

hemiansatus to ansatus zones. Thelodont scales referred here to Australolepis sp. cf. A. seddoni come from near

Śniadka village, from samples dated as hemiansatus to rhenanus/varcus zones. This increases the known range

for the genus from its original find in Western Australia. The presence of a thelodont in the late Middle Devonian

in Poland extends the known distribution of turiniids around the peri-Gondwana shorelines of Palaeotethys.

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Authors and Affiliations

Susan Turner
Michał Ginter
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Abstract

A microfauna of small shelly fossils (SSF) is reported here for the first time from middle Cambrian (Series 3, Stage 5) subsurface strata of the Torgau-Doberlug Syncline (TDS), Central Germany. Considering that this microfauna is strongly limited and poorly preserved the material is quite abundant and diverse. The assemblage consists of molluscs (pelagiellids, bivalves), coeloscleritophorans (chancelloriids, halkieriids), poriferids, protoconodonts, cambroclaves, hyoliths, brachiopods, and disarticulated echinoderm remains. Additionally, a probable pterobranch hemichordate is noted. The assemblage is dominated by epifaunal suspension feeders from mid- to outer shelf depositional settings. Stratigraphically it represents (together with rare trilobites) the oldest middle Cambrian (Series 3, Stage 5) fauna known from Central Germany and the entire Saxothuringian Zone. Regardless the taphonomic problems related to the SSF occurrence, close palaeobiogeographic relations are indicated with the Mediterranean shelf of West Gondwana (especially with the areas of southwestern Europe and Morocco). The reported microfauna coupled with recent trilobite and palynomorph research supports assumptions that the Cambrian succession in the TDS is by far more complete than hitherto suggested, emphasizing its importance as a region yielding Cambrian rocks in Central Europe.

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Authors and Affiliations

Abubaker Atnisha
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Abstract

Molluscan fossils accompanied by familiar SSF have been recovered from Early Cambrian limestone erratics in the Early Miocene glaciomarine Cape Melville Formation of King George Island, West Antarctica. The molluscan fauna comprises the hyoliths Conotheca, Microcornus, Parkula, Hyptiotheca, “Hyolithes”, the helcionelloids ?Pararacornus, Yochelcionella, Anabarella, the low dextrally coiled Pelagiella and the high helically coiled Beshtashella, as well as the problematic mollusc Cupitheca. Most of described species are recorded here for the first time from Antarctica. The lithological and fossil contents of the erratics are almost the same as from autochthonous successions the Shackleton Limestone in the Argentina Range and Transantarctic Mountains. Early Cambrian outcrops around the Weddell Sea are a probable source of the erratic boulders. The Antarctic fauna is very similar to that from uppermost Botomian and Toyonian carbonate deposits in the Cambrian Basins of South Australia. These faunal and facies similarities between Antarctica and Australia confirm their neighbouring position and common biotic and basin evolution on the Cambrian Gondwana margin.

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Authors and Affiliations

Ryszard Wrona
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Abstract

In the Balkans, the Serbo-Macedonian Unit (SMU), Serbia, is thrust bounded by the composite Tethyan Vardar Zone and the Carpatho-Balkanides. The SMU actually emerges from beneath the Neoalpine Miocene–Pliocene deposits. Both provenance and geodynamic position of the SMU are poorly known and still debated. This paper reviews the data hitherto published and includes some new field data interpretations. The SMU is composed of a Neoproterozoic–Cambrian high-grade (para- and ortho-) gneiss with peraluminous magmatic arc components (560–470 Ma). The SMU is in the contact with Neoproterozoic upper Ordovician–Carboniferous low-grade metasedimentary succession of an accretionary wedge assembly represented by the Supragetic basement. The SMU basement became folded, sheared and metamorphosed around 490–450 Ma. Paleomagnetic data point to high southern latitudes and a peri-Gondwanan position of the SMU at that time, which concurs with glaciomarine evidence recorded from the upper Ordovician sediments at the base of an accretionary wedge succession. Based on the published data and field survey in the Stalać region, we correlate the SMU with the pre-Mesozoic gneiss terrane exposed in the Strona-Ceneri zone of the Alps. This terrane, identified as the Cenerian orogen of the Alaskan subduction type, developed at an active margin of Gondwana during middle Ordovician times. The SMU basement, with augen and migmatitic gneisses and arc-related peraluminous magmatic bodies, developed at this margin as part of the Cenerian belt or its equivalent. Such an orogenic edifice proved transient and in the earliest Silurian the SMU fragments drifted away being bound for Baltica (amalgamated Moesian microplate and Danubian terrane) to which they became accreted in the Carboniferous and included in the southern European branch of the Variscan orogen (Marginal Dacides/Carpatho-Balkanides). Despite considerable Variscan and Alpine reworking, the pre-Variscan, Cenerian-type crustal assembly along with an inferred boundary between the magmatic arc and the accretionary wedge, accompanied by back-arc/forearc deposits, are still decipherable in the Western Balkan countries.
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Authors and Affiliations

Darko Spahić
1
ORCID: ORCID
Zoran Bojić
1
Danica Popović
1
Tivadar Gaudenyi
2
ORCID: ORCID

  1. Geological Survey of Serbia, Rovinjska 12, 11000 Belgrade, Serbia
  2. Geographical Institute “Jovan Cvijić” of the Serbian Academy of Sciences and Arts, Djure Jakšića 9, 11000 Belgrade, Serbia

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