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EN
The aim of this study was to establish the stratigraphic extent of a putative Tournaisian Stage within the Carboniferous succession in the Lublin Basin. The oldest part of the succession, known as the Huczwa Formation and comprising depositional sequences 1-4, was investigated based on lithofacies analysis, sequence stratigraphy and petrographic studies. The article provides descriptions of depositional sequences, parasequences (cyclothems) and lithofacies that were formed in a range of environments (elements of depositional architecture) and as a result of volcanic processes - lava and pyroclastic eruptions and chemical weathering of their products. Correlation of the sequence stratigraphy to the West European and global Carboniferous chronostratigraphic divisions, as well as to the Khoriv suite in the Lviv-Volyn Basin in adjacent Ukraine, indicates a putative late Tournaisian age for sequence 1, and a late Visean age for sequences 2-4. There is a stratigraphic gap between sequences 1 and 2, spanning probably the uppermost Tournaisian and the lower and middle Visean. The upper Tournaisian is represented by the FRST-LST deposits of sequence 1, comprising mainly volcaniclastic conglomerates and sandstones developed in braided-river channels and incised valleys with hyperconcentrated flow processes. These deposits are represented by polymictic paraconglomerate and lithic/sublithic/subarkose arenites or sublithic wackes, and contain predominantly grains of acidic and alkaline volcanic and igneous rocks. This material probably came from the Łuków-Wisznice Elevation and the Volynian Polesia region, located to the NE and E of the Lublin Basin. In the uppermost part of sequence 1, volcanic rocks and tuffs appear which developed during the activity of at least three volcanic cones in the Lublin Basin. The volcanoes were the source of alkaline lavas in the central and SW areas of the basin, and of acidic lavas in the SE area, previously undescribed. The Visean sequences 2-4 consist of the FRST-LST sediments deposited within incised valleys. The TST and HST deposits accumulated mainly in a shallow ramp-type carbonate shelf, shallow clayey shelf and deltaic environments.
EN
A sample of late Viséan limestone from the Włodawa IG-4 borehole, east of Lublin, Poland, yielded a piece of a tooth and a few hundred well-preserved scales comparable to those of “Ctenacanthus” costellatus Traquair, 1884 from Glencartholm, Scotland, UK. Most of the scales are typical compound body scales of the ctenacanthid type. Their crowns are composed of several separate odontodes whose distal ends are turned backwards and bases are characterised by concave undersides. In the material, there are also sparse scales with similar crowns but with flat or convex bulbous bases, as well as ornamented plates and single, star-like denticles, probably from the head region. The taxonomic status of “Ctenacanthus” costellatus was analysed and a new generic name for that species, viz. Glencartius gen. nov., is proposed.
EN
A new species of micromorphic articulate brachiopod (Rhynchonellida) Lambdarina jugowiensis sp. nov., from the upper Viséan (Sokolec Beds) of central Sudetes, SW Poland, is described. The studied specimens are calcified, what makes them unique in respect of their state of preservation. The material is represented by a full range of growth stages; from brephic to gerontic. Based on its morphological features and the palaeogeographical distribution of all its known species, two main evolutionary lines are proposed for the genus; the Australian and the European ones. Lambdarina was widely distributed in the equatorial-tropical waters of marginal seas of the Palaeotethys Ocean, mostly during Mississippian time.
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