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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

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2021

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Vol. 65, No. 4

art. no. 52

EN

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).

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Facies patterns and depositional processes in two Frasnian mixed siliciclastic-carbonate systems in the Cantabrian Mountains, northwest Spain

Van Loevezijn Gerard B.S., Raven J.G.M.

Geologos

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2020

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Vol. 26, No. 1

1--23

EN

Relative sea level fluctuations during the Frasnian generated two shallow-marine, mixed siliciclastic-carbonate successions in the Devonian Asturo-Leonese Basin. Each system represents a third-order sequence-stratigraphical unit deposited in the same basin during comparable extreme greenhouse conditions without nearby fluvial entry points. Depositional control on the siliciclastic and carbonate distribution was driven by relative sea level fluctuations, basin geometry, availability of sand and the way sediment was distributed by shelf currents. Early Variscan flexural bending of the continental crust changed the basin shape from a shelf with a gradual profile and low dip (early Frasnian) towards a shelf with a steep depositional dip (late Frasnian). Shelf distribution changed from along-shelf transport (early Frasnian) towards offshore-directed gravity flows (late Frasnian). As a consequence, siliciclastic-carbonate distribution changed from a predominance of skeletal carbonate in the proximal shoreface – foreshore area and siliciclastic predominance distally (early Frasnian), to a distribution pattern with proximal shoreface skeletal carbonates, offshore muddy carbonates and a siliciclastic zone in between where gravity flows distributed the siliciclastic sediment down dip (late Frasnian).

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On the erroneous identification of a turiniid thelodont in the Middle/Upper Devonian boundary beds of the Middle Urals

Märss T., Ivanov A.

Acta Geologica Polonica

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2018

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Vol. 68, no. 3

455

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The youngest Devonian record of "Housean pits" in ammonoids

Rakociński M.

Geological Quarterly

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2012

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Vol. 56, No 2

387-390

EN

An unusual occurrence of parasitic "Housean pits" in internal mould of ammonoid specimen referred to as Felisporadoceras cf. subvaricatum (Sobolew) from Middle Famennian of Poland are described. Hitherto the youngest representatives of goniatites showing a pitting on the internal moulds were known from the Middle Devonian (lower Givetian), thus, most probably the presented material constitutes the youngest world record of this phenomenon.

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Biostratygrafia konodontowa dewonu górnego lubelszczyzny

Narkiewicz K., Bultynck P.

Prace Państwowego Instytutu Geologicznego

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2011

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T.196

193--254

PL

Zbadano 203 próbki konodontowe, w tym 114 pozytywnych, z 15 profili wiertniczych, w większości z utworów franu formacji modryńskiej, a ponadto z fameńskiej formacji bychawskiej i firlejskiej. Ze 100 próbek z profili franu uzyskano 2139 okazów zaliczonych do 9 rodzajów, w obrębie których oznaczono 81 taksonów niższego rzędu. Czternaście gatunków znaleziono i udokumentowano w Polsce po raz pierwszy. Wobec braku form indeksowych wiek zespołów określano głównie na podstawie zestawienia zasięgów stratygraficznych wszystkich elementów znalezionych w próbce. Najwyższą część formacji telatyńskiej w centralnej części basenu lubelskiego, tuż poniżej podstawy formacji modryńskiej, zaliczono do franu dolnego (profile otworów Giełczew PIG 5, Mełgiew 2). Datowania utworów frańskich pozwalają też na zawężenie wieku poszczególnych ogniw tworzących formację modryńską. Udokumentowano diachronizm górnej granicy formacji modryńskiej, która wypada w famenie dolnym w profilu Opole Lubelskie IG 1, a w najwyższym franie w profilu Giełczew PIG 5. Granica franu z famenem biegnie w pobliżu granicy formacji modryńskiej i firlejskiej (Korczmin IG 1). Granica między formacją bychawską a firlejską w segmentach lubelskim i stężyckim przebiega w obrębie wyższego famenu dolnego albo niższego środkowego. W segmencie komarowskim datowanie stropowych partii formacji firlejskiej sugeruje natomiast, że dolna granica formacji hulczańskiej wypada w pobliżu granicy famenu dolnego i środkowego.

EN

Investigations were based on 203 conodont samples, including 114 positive, from 15 borehole sections mainly representative of the Modryń Formation (Frasnian), and also comprising the Famennian Bychawa and Firlej formations. The Frasnian conodont collection was obtained from 100 samples which contained 2139 specimens attributed to 9 genera and 81 lower rank taxa, including 14 species found and documented in Poland for the first time. Age of the assemblages was determined mainly basing on a comparison of stratigraphic ranges of all elements found in a sample. Uppermost part of the Telatyń Formation, just below the base of the Modryń Formation was ascribed to the Lower Frasnian in the Lublin (Central) Segment of the Lublin Basin (Giełczew PIG 5, Mełgiew 2). The conodont biostratigraphy of the Frasnian sections allows to constrain also the age of particular members constituting the Modryń Formation. Upper formation boundary appears diachronous, running in the Lower Famennian in the Opole Lubelskie IG 1 and in the uppermost Frasnianin the Giełczew PIG 5. The boundary between the Bychawa and Firlej formations in the Central and Stężyca (NW) segments is traced in the upper Lower Famennian or lower Middle Famennian. On the other hand, in the Komarów Segment (SE) the data from the uppermost part of the Firlej Formation suggest that the base of the overlying Hulcza Formation runs near the Lower/Middle Famennian boundary.

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Source and depositional processes of coarse-grained limestone event beds in Frasnian slope deposits (Kostomłoty-Mogiłki quarry, Holy Cross Mountains, Poland)

Vierek Aleksandra

Geologos

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2010

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Vol. 16, No. 3

153--168

EN

The Kostomłoty-Mogiłki succession is situated in the Kostomłoty transitional zone between the shallow-water Kielce stromatoporoid-coral platform and the deeper Łysogóry basin. In the Kostomłoty-Mogiłki quarry, the upper part of the Szydłówek Beds and Kostomłoty Beds are exposed. The Middle-Upper Frasnian Kostomłoty Beds are composed of shales, micritic and nodular limestones with abundant intercalations of detrital limestones. The dark shales and the micritic and nodular limestones record background sedimentation. The interbedded laminated and detrital limestones reflect high-energy deposition (= event beds). These event beds comprise laminated calcisiltites, fine-grained calcarenites, coarse-grained grain-supported calcirudites fabrics, and matrix-supported calcirudites. The material of these event beds was supplied by both erosion of the carbonate-platform margin and cannibalistic erosion of penecontemporaneous detrital limestones building the slope of this platform. Storms and the tectonic activity were likely the main causes of erosion. Combined and gravity flows were the transporting mechanisms involved in the reworking and redeposition.

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Storm-dominated deposition on a Frasnian carbonate platform margin (Wietrznia, Holy Cross Mts., Poland)

Vierek A.

Geological Quarterly

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2007

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Vol. 51, No 3

307-318

EN

The Wietrznia quarry in Kielce is situated between the shallow-water Devonian carbonate platform in the Kielce region and the deeper Łysogóry basin. This palaeogeographic setting affected carbonate sedimentation in Late Devonian times. The transitional facies of the Wietrznia Frasnian comprises two over lapping types of deposits: (1) micritic and marly limestone of shelf basin facies and (2) coarse-grained limestone of fore-reef facies. The first type includes laminated- and graded micritic limestone and modular limestone. The second includes intraformational conglomerates and breccias, and crinoidal limestone. The limestones in the middle Wietrznia Beds formed within storm wave basein a shal ow (possibly only a few tens of metres) sea that deepened eastwards. Storms are likely to have been the main cause of erosion and transport. In the western part of the quarry, proximal tempestites show evidence of amalgamation and cannibalism as do some high-energy flat-pebble conglomerates. With abating storm winds, finer-grained graded and laminated limestones accumulated. To ward the eastern part of the quarry, the high-energy effects of near-shore storm waves are less evident; the deposits there are transitional or more distal tempestites.

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Paleomagnetism and remagnetization of Upper Devonian synorogenic clastic sediments from the Pogorzała Formation (Świebodzice Depression, West Sudetes, Poland

Kądziołko-Hofmokl M., Jeleńska M., Aifa T., Edel J.B., Żelaźniewicz A.

Geologia Sudetica

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1999

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Vol. 32, nr 2

113-126

EN

The Upper Devonian highly polymict conglomerates (site 26) and sandstones with clasts (site 27) of the Pogorzała Formation in the synorogenic Świebodzice Depression, West Sudetes, are hydrothermally altered and show signs of penetration by mineralized fluids. Nearly all the magnetic minerals present (mainly Fe-oxides and pyrrhotite accompanied by Fe-hydroxides) are of secondary origin. Rocks from each site carry multicomponent natural remanence composed of Mesozoic/post-Mesozoic and Palaeozoic components. In the conglomerates (site 26) two Palaeozoic components, labelled P and C, occur in the matrix and pebbles, whereas in the sandstones with large clasts (site 27) only one Palaeozoic component labeled C1 occurs. This means that the results of the conglomerate test for both sites are negative and the studied rocks were remagnetized during several remagnetization episodes. The overprints present in site 26 closely fit the reference data for the Baltica Plate for the Early Permian component (P) and Viséan component (C). The overprint present in site 27 is slightly shifted from the Westphalian (C1) segment of the reference path. The P component is also close to the path of polar wander for Variscan Europe.