BazTech - Yadda

1

Summary of a decade of research at the Owadów–Brzezinki Lagerstätte (Tithonian, central Poland): A review and perspectives for the future

Błażejowski Błażej, Weryński Łukasz, Wierzbowski Andrzej, Michalska Monika, Hryniewicz Krzysztof, Uchman Alfred, Kugler Stanisław, Bącal Paweł, Hołda-Michalska Aleksandra

Volumina Jurassica

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2023

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Vol. 21

83--98

EN

For over ten years, the Lower to Upper Tithonian boundary beds cropping out in the Owadów–Brzezinki quarry have yielded numerous fossils of ammonites, bivalves, brachiopods, xiphosurans, decapods, insects, and vertebrates – including actinopterygian fishes and various reptiles and others, all of which exhibit fine preservation of their anatomical details due to special environmental conditions during their fossilization. The Owadów–Brzezinki section is also important for stratigraphical correlations because it contains ammonite faunas indicative of the NE European and NW European Subboreal zonal schemes, as well as Tethyan calpionellids. The whole faunal as- semblage, which represents taxa of many iconic groups of Mesozoic animals, has created the opportunity to establish the ‘Owadów– Brzezinki geopark’, a geoeducation area where the public, and especially the young, can learn about the beauty of the natural history of the region.

2

Palaeobiogeography of Late Bajocian–Tithonian ammonites of northeastern Iran

Majidifard Mahmoud Reza

Geotourism / Geoturystyka

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2023

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nr 1-2 (72-73)

46--46

EN

Jurassic rocks are widely distributed and superbly exposed in the Alborz Mts. (northern Iran) and Koppeh Dagh (northeastern Iran). The Lower Jurassic and large parts of the Middle Jurassicare characterized by a thick siliciclastic succession, whereas the Upper Bajocian to Tithonian rocks are predominantly carbonates, which represent a platform, slope and basin system. The Upper Bajocian-Tithonian ammonite faunas the NNE Iran are mostly of Submediterranean affinity, but elements of Subboreal, Mediterranean, and Ethiopian provinces are occasionally intermingled. Palaeobiogeographically the Late Bajocian to Bathonian ammonites belong to Submediterranean Province, as elsewhere in north and central Iran. This is supported by the occurrence of ammonites such as Garantiana and Morphoceras and some cosmopolitan taxa such as Cadomites and Oxycerites. In order to unravel the origin of the faunal elements and their migration routes, the relationship of the ammonite fauna of Iran to that of other regions was evaluated. On the whole, at the species level, the Toarcian to Early Bajocian ammonite faunas of northern and central Iran show a close relationship to that of northwestern Europe. A characteristic feature of this fauna is the scarcity of Phylloceratidae (accounting for less than 1% up to 3%) and the absence of Lytoceratidae. Remarkably, from Late Bathonian onward to Kimmeridgian, Phylloceratidae account for more than 50% of the ammonites fauna. Palaeogeographic reconstructions show the position of the Iranian plate (North and Central Iran) during the Middle Jurassic time at the southern margin of Eurasia at a palaeo-latitude of around 30° N which rather corresponds to European regions (Enay & Cariou, 1997). The open migration routes across pericontinental shelf seas along the northern Tethyan margin that were approximately parallel to palaeo-latitudes may explain the strong affinities of the Late Bajocian–Bathonian ammonites of northern and Central Iran to those of the Submediterranean Province. The Callovian ammonite fauna has a typical northwest Tethyan character, and belong to the Submediterranean faunal province (Seyed-Emami et al., 2013), and are largely dominated by Phylloceratidae ammonites. These pelagic taxa that preferred open oceanic conditions are accompanied consistently by Perisphinctidae, Reineckeiidae, Oppeliidae (Hecticoceratinae), Macrocephalitidae , Tulitidae, Aspidoceratidae (Parawedekindia, Peltoceras). On the other hand, this is supported by the occurrence of Submediterranean ammonites such as Macrocephalites, Pachyceras, and some cosmopolitan taxa such as Hecticoceras and Reineckeia. Some taxa from the Oxfordian- Kimmeridgian belong to the Western Tethys Province (Sequeirosia and Passendorferia) or Subboreal Province (Cardioceras). It is remarkable that, besides some cosmopolitan ammonites, there is no direct connection with faunas from southwestern Iran, western India and the southern Tethys. Finally, the Tithonian ammonite faunas of northeastern Iran are mostly of Submediterranean affinity (Seyed-Emami et al., 2013). However elements of the Mediterranean faunal provinces occasionally occur. In order to unravel the origin of the faunal elements and their migration routes, the relationship of the ammonite fauna of Iran to that of other regions need to be analysed in the future. Especially the appearance of several allegedly regionally restricted Ataxioceratidae such as Phanerostephanus, Nannostephanus, Nothostephans and the Oppeliidae as Oxylenticeras, which occur in Ethiopian Province (Page, 2008) is of great palaeobiogeographical interest.

3

New records of Tmaegoceras lacordarii (Michelin, 1835) from the Lower Jurassic Arietenkalk Formation of SW Germany and its systematic relationships

Schweigert Günter, Scherzinger Armin, Gräbenstein Stefan

Volumina Jurassica

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2021

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Vol. 19, no. 1

95--108

EN

New material of the enigmatic cosmopolitan ammonite genus Tmaegoceras Hyatt, 1889 is reported from the upper Lower Sinemurian (Bucklandi Zone, ‛cf. pinguisʼ Biohorizon) of SW Germany. It is better preserved than previously described material. All specimens are assigned to Tmaegoceras lacordarii (Michelin, 1835), an almost forgotten subjective senior synonym of Tmaegoceras crassiceps Pompeckj, 1901. The presence of an extreme rursiradiate ribbing style in some specimens allows a better understanding of this genus and provides a hint for its systematic affiliation. This diagnostic ribbing style is shared with some extremely rare Alpine taxa such as Ammonites salinarius Hauer, 1846 and “Arietites” subsalinarius Wähner, 1891. Tmaegoceras is included here in Pseudotropitinae Donovan, 1973. Pseudotropitinae are possibly an early offshoot of Arietitidae indigenous of the Panthalassa Realm that occasionally spread into the Tethys and its adjacent shelves. A phyletic relationship with Late Triassic Tropitidae Mojsisovics, 1875, however, cannot be excluded either.

4

In defence of invertebrate fossil taxonomy

Fedorowski Jerzy

Acta Geologica Polonica

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2021

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Vol. 71, no. 3

249--258

EN

Starting from a subjective viewpoint on the decreasing interest in invertebrate fossil taxonomy, this essay discusses its importance in palaeobiological studies exemplified with cases from the palaeobiogeography and palaeoecology of rugose corals, and aims at provoking a discussion on the topic. The possible causes of this negative declining trend include inherent problems of palaeontological taxonomy, and changing systems in science and higher education.

5

The Bajocian to Kimmeridgian (Middle to Upper Jurassic) ammonite succession at Sentralbanken High (core 7533/3-U-1), Barents Sea, and its stratigraphical and palaeobiogeographical significance

Andrzej Wierzbowski, Morten Smelror

Volumina Jurassica

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2020

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Vol. 18, no. 1

1--22

EN

Ammonites recovered from Upper Bajocian to Upper Kimmeridgian strata in a core drilled at Sentralbanken High in the northern Barents Sea are described and chronostratigraphically interpreted. The lower part of the core comprises Upper Bajocian to Upper Callovian deposits of the Fuglen Formation with ammonites of the genus Cranocephalites near the base, and Longaeviceras in the upper part. The overlying Oxfordian to Kimmeridgian deposits of the Hekkingen Formation are thin and condensed. The Hekkingen Formation is dominated by Boreal cardioceratid ammonites (Cardioceras, Amoebites, Euprionoceras, Hoplocardioceras), with numerous Subboreal aulacostephanid ammonites (Rasenia, Zenostephanus) at two levels. The occurrences of Boreal and Subboreal ammonites are discussed in relation to the palaeogeography and fluctuations of ammonite faunas within the Boreal Realm during the Kimmeridgian with special attention to levels rich in Subboreal ammonites whose appearance has been controlled by tectonic and climatic factors. The uppermost part of the succession deposited during a time of maximum flooding in the Late Kimmeridgian is dominated by Boreal ammonites.

6

A microconchiate Hypowaagenia Schweigert and Schlampp, 2020 (Aspidoceratidae, Hybonoticeratinae) from the Upper Jurassic of Southern Germany

Schweigert Günter, Schlampp Victor

Volumina Jurassica

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2020

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Vol. 18, no. 2

115--120

EN

The previously unknown microconch which corresponds to the recently introduced Late Jurassic aspidoceratoid ammonite genus Hypowaagenia Schweigert and Schlampp, 2020, is reported from beds of the topmost Platynota Zone or basal Hypselocyclum Zone of Franconia. This record indicates that these exotic ammonite findings are not of long-drifting necroplanktonic shells, but stem from animals that have spread over this area after immigration from the Tethys

7

Detailed biostratigraphy of the Middle Callovian – lowest Oxfordian in the Mikhaylov reference section (Ryazan region, European part of Russia) by ammonites

Kiselev D. N., Rogov M. A.

Volumina Jurassica

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2018

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Vol. 16, no 1

73--186

EN

Study of the sections near the Mikhaylov (Ryazan region) has made it possible to improve the infrazonal subdivision of the Middle Callovian – Lower Oxfordian of the European Russia by ammonites. The Athleta Zone is the most complete in the studied sections. A sequence of kosmoceratid biohorizons (phaeinum, proniae, rowlstonense and kuklikum) is established here, as well as infrazonal units based on a phylogenetic sequence of species of the genus Funiferites. A study of the paleobiodiversity and frequency of occurrence of ammonites at different intervals of the section showed that the ammonite assemblages of the Athleta Zone are Sub-Boreal or Sub-Tethyan, while in the Lamberti Zone they are Boreal, and in the Lower Oxfordian they are Arctic. It is also shown that the change in ammonite composition in the sections coincides with the cycles of transgressions and regressions of Boreal basins. New species and subspecies of the ammonites Funiferites allae compressum, Cadoceras (Eichwaldiceras) intermedium, Brightia (B.) lominadzei, B. (B.) progzhellensis, B. (B.) eccentrtica, B. (Glyptia) canaliculata stankevitchae, Zieteniceras rarecostatum are described.

8

Stem chondrichthyan microfossils from the Lower Old Red Sandstone of the Welsh Borderland

Burrow C. J., Turner S.

Acta Geologica Polonica

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2018

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Vol. 68, no. 3

321--334

EN

Placoid and polyodontode scales of stem chondrichthyans have been found in the early Lochkovian “Ditton Group” of the Brown Clee Hill district, Shropshire, England and at Talgarth, south Wales. One of the forms is assigned to a new species of Altholepis Karatajūtė-Talimaa, 1997, a genus already recognised from Lochkovian shallow marine deposits in Celtiberia, Spain and the Northwest Territories, Canada as well as the type locality in Podolia, Ukraine. Altholepis salopensis sp. nov. is based on small polyodontode scales with typically three to eight high odontodes; the scale form was previously considered to belong to acanthodian “Nostolepis” robusta (Brotzen, 1934). The structure of other scales formerly assigned to “Nostolepis” robusta has led us to erect a new genus Jolepis for this scale form, which differs from Altholepis in lacking an ordered layout of odontodes. Jolepis robusta (Brotzen, 1934), originally (and possibly still) considered to be an acanthodian, is also known from the Baltic countries, Russia, and northern Germany (ex erratic limestones). Scales of acanthodian Parexus recurvus Agassiz, 1845, and/or possibly from the stem chondrichthyan Seretolepis elegans Karatajūtė-Talimaa, 1968 (scales of these two taxa are barely distinguishable), and of stem chondrichthyan Polymerolepis whitei Karatajūtė-Talimaa, 1968 are also present. Altholepis, Jolepis gen. nov., Seretolepis Karatajūtė-Talimaa, 1968 and Polymerolepis KaratajūtėTalimaa, 1968 are found in marine deposits elsewhere; the British occurrence of these taxa adds to the debate on the sedimentological origins of the Lower Old Red Sandstone deposits in the Welsh Borderland. The geographic range of several early sharks is now known to extend around the Old Red Sandstone continent and beyond.

9

From museum drawers to ocean drilling: Fenneria gen. nov. (Bacillariophyta) offers new insights into Eocene marine diatom biostratigraphy and palaeobiogeography

Witkowski J.

Acta Geologica Polonica

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2018

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Vol. 68, no. 1

53--88

EN

Triceratium barbadense Greville, 1861a, T. brachiatum Brightwell, 1856, T. inconspicuum Greville, 1861b and T. kanayae Fenner, 1984a, are among the most common diatoms reported worldwide from lower to middle Eocene biosiliceous sediments. Due to complicated nomenclatural histories, however, they are often confused. A morphometric analysis performed herein indicates that T. brachiatum is conspecific with T. inconspicuum, and that both were previously often misidentified as T. barbadense. Triceratium barbadense sensu stricto is a distinct species similar to Triceratium castellatum West, 1860. Triceratium brachiatum and T. kanayae are transferred herein to a new genus, Fenneria, for which a close phylogenetic relationship with Medlinia Sims, 1998 is proposed. A review of the geographic and stratigraphic distribution of Fenneria shows that the best constrained records of its occurrences are found at DSDP Site 338, and ODP Sites 1051 and 1260. The ages of the base (B) and top (T) of each species’ stratigraphic range are calibrated here to the Geomagnetic Polarity Timescale either directly or inferred via correlation with dinocyst biostratigraphy. Latitudinal diachroneity of ~7 million years is documented for F. brachiata, which disappears earlier in tropical and mid-latitude sites than in the northern high latitudes. These observations, coupled with a preliminary compilation of the Chron C20n taxonomic composition of pelagic diatom assemblages for Sites 338, 1051 and 1260, indicate that diatoms diversified palaeobiogeographically considerably earlier than the Eocene-Oligocene Transition, as commonly believed. This study also emphasizes the importance of the detailed examination of specimens from both museum collections and deep-sea cores as a step toward enhancing the utility of Palaeogene diatoms in palaeoceanographic and palaeoenvironmental reconstructions.

10

New finds of well-preserved Tithonian (Late Jurassic) fossils from Owadów–Brzezinki Quarry, Central Poland: a review and perspectives

Błażejowski B., Gieszcz P., Tyborowski D.

Volumina Jurassica

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2016

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Vol. 14, no. 1

123--132

EN

Here we briefly report the discovery of new, exceptionally well-preserved Late Jurassic (Tithonian) fossils from Owadow- Brzezinki quarry - one of the most important palaeontological sites in Poland. These finds which comprise organisms living originally in different environments indicate that the Owadow-Brzezinki site represents a link - most probably in a form of open marine passages - betweeen distinct palaeobiogeographical provinces. This creates an unprecedented opportunity for better recognition of the regional palaeobiogeography of adjacent European areas during the Late Jurassic.

11

The earliest ostracods from the Ordovician of the Prague Basin, Czech Republic

Lajblová K., Kraft P.

Acta Geologica Polonica

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2014

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Vol. 64, no. 4

367--392

EN

The earliest ostracods from the Bohemian Massif (Central European Variscides) have been recorded from the Middle Ordovician of the Prague Basin (Barrandian area), in the upper Klabava Formation, and became an abundant component of fossil assemblages in the overlying Šárka Formation. Both early ostracod associations consist of eight species in total, representing mainly eridostracans, palaeocopids, and binodicopids. The revision, description, or redescription of all species and their distribution in the basin is provided. Their diversification patterns and palaeogeographical relationships to ostracod assemblages from other regions are discussed.

12

A new species of Lambdarina (Rhynchonellida, Brachiopoda) from the Viséan of central Sudetes (Poland) and its phylogenetic position

Muszer J.

Acta Geologica Polonica

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2014

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Vol. 64, no. 1

1--12

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.

13

Late Cenomanian.Turonian (Cretaceous) ammonites from Wadi Qena, central Eastern Desert, Egypt : taxonomy, biostratigraphy and palaeobiogeographic implications

Nagm E., Wilmsen M.

Acta Geologica Polonica

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2012

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Vol. 62, no. 1

63-89

EN

In Egypt, marine Upper Cenomanian.Turonian strata are well exposed in the Eastern Desert. The southernmost outcrops are located in the central part of Wadi Qena, where the lower Upper Cretaceous is represented by the fossiliferous Galala and Umm Omeiyid formations. From these strata, numerous ammonites have been collected bed-by-bed and 13 taxa have been identified, which are systematically described herein. Four of them (Euomphaloceras costatum, Vascoceras globosum globosum, Thomasites gongilensis and Pseudotissotia nigeriensis) are recorded from Egypt for the first time. The ammonite ranges are used for a biostratigraphic zonation of the lower Upper Cretaceous succession in the northern and central part of Wadi Qena: the Upper Cenomanian.Lower Turonian has been subdivided into five biozones (including a new upper Lower Turonian biozone based on the occurrence of Pseudotissotia nigeriensis), and one biozone has been recognized in the Upper Turonian. Palaeobiogeographically, the ammonite assemblage has a Tethyan character. During the Early Turonian, influences of the Vascoceratid Province were predominant with strong affinities to typical Nigerian faunas. This shows the significance of faunal exchange between Egypt and Central and West Africa via the Trans-Saharan Seaway. Compared to contemporaneous ammonoid faunas from the northern part of the Eastern Desert, Boreal influences are much less obvious in Wadi Qena. Thus, the present study greatly enhances the knowledge of the Late Cretaceous palaeobiogeography and biostratigraphy of Egypt and adjacent areas.

14

Uppermost Devonian ammonoids from Oklahoma and their palaeobiogeographic significance

Becker R., Mapes R.

Acta Geologica Polonica

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2010

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Vol. 60, no. 2

139-163

EN

The upper part of the Woodward Shale of southern Oklahoma has yielded the first moderately diverse North American ammonoid fauna from the uppermost Famennian (Upper Devonian VI). It includes six species from three clymeniid and one goniatite family: Kielcensia vagabunda sp. nov., Riphaeoclymenia polygona sp. nov., R. pontotocensis sp. nov., Cyrtoclymenia cf. procera Czarnocki, 1989, Spirosporadoceras overi gen. nov. sp. nov., and a poorly preserved different juvenile sporadoceratid that may represent a second new genus. For comparison, the related Spirosporadoceras delicatum sp. nov. from Germany is described. Kielcensia specimens from Oklahoma represent the first uncontested record of triangularly coiled wocklumeriids from North America. Together with Riphaeoclymenia, the Oklahoma fauna has similarities and strong biogeographical ties with the far distant Holy Cross Mountains of Poland. Kielcensia and Riphaeoclymenia are missing from the diverse contemporaneous ammonoid faunas of Middle and Southern Europe, which were located between the Oklahoma and the Polish occurrences. Geographically intermediate contemporaneous Moroccan faunas also show a fundamentally different composition but the Afro-Appalachian migration route must have been viable in the uppermost Famennian. Migrations through regions without leaving a trace in available very rich fossil records ("ghost distributions") create a bias for the palaeobiogeographical analysis of nektonic organisms. The faunal composition of the Woodford Shale suggests a control of ammonoid distribution patterns by palaeoecological factors that are not recognizable in the lithofacies.

15

Paleogeografia południowo-wschodniej Azji i jej związek z rozmieszczeniem wczesnojurajskich budowli małżowych (z grupy Lithiotis) na tle wielkiego wymierania trias/jura

Krobicki M., Golonka J.

Geologia / Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie

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2009

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T. 35, z. 3/1

79-90

EN

The separation of Laurasia and Gondwana, which was initiated by the Triassic break-up of Pangea, continued during Early-Middle Jurassic times. The origin of the narrow sea strait. so-called "Hispanic Corridor", took place between these two continents and connection of the Panthalassa Ocean (Proto-Pacific) and western (Alpine) Tethys gradually started in Early Jurassic, most probably in Sinemurian-Pliensbachian times. Recovery of marine fauna after Triassic/Jurassic mass extinction event was mainly marked by world-wide distribution of Lithiotis-type bivalve buildups. They indicate mainly shallow-marine/lagoon-type carbonate sedimentation and palaeogeographic/geodynamic regimes during break-up of Pangea in Pliensbachian-Early Toarcian times.

16

When the "primitive" shark Tribodus (Hybodontiformes) meets the "modern" ray Pseudohypolophus (Rajiformes) : the unique co-occurrence of these two durophagous Cretaceous selachians in Charentes (SWFrance)

Vullo R., Neraudeau D.

Acta Geologica Polonica

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2008

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Vol. 58, no. 2

249-255

EN

The palaeoecology and palaeobiogeography of two Cretaceous selachian genera, Tribodus BRITO & FERREIRA, 1989 and Pseudohypolophus CAPPETTA & CASE, 1975, are briefly discussed. These two similar-sized taxa developed an analogous pavement-like grinding dentition, characterized by massive teeth with a rhomboidal to hexagonal occlusal surface. Although both genera appear to have been euryhaline forms, the hybodont Tribodus occurred in fresh/brackish water habitats (e.g. deltas) to shallow marine lagoons, whereas the ray Pseudohypolophus lived in brackish water to coastal marine environments. Palaeobiogeographically, their global distribution displays two distinct but adjoined areas, with Tribodus being present in the northern part of Gondwana (Brazil and North Africa), and Pseudohypolophus occurring on both sides of the North Atlantic (North America and Western Europe). However, the two genera coexisted during Cenomanian times within a small overlap zone, localized in western France. A trophic competition may have arisen from this situation between these two selachians belonging to the same trophic guild. This peculiar situation is well documented within the Cenomanian transgressive series of Charentes (SW France), where a turnover between the two forms is observed (replacement of Tribodus by Pseudohypolophus).

17

Nanoplankton wapienny górnokredowych facji pelagicznych jednostki podśląskiej polskich Karpat fliszowych

Jugowiec-Nazarkiewicz M.

Biuletyn Państwowego Instytutu Geologicznego

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2007

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nr 426

53-70

PL

W pelagicznych osadach jednostki podśląskiej (marglach węglowieckich, marglach typu frydeckiego, marglach żegocińskich, piaskowcach z Rybia) oraz w marglach bakulitowych jednostki skolskiej i marglach z Bonarki występujących na monoklinie śląsko-krakowskiej (odsłonięcie Bonarka w Krakowie) stwierdzono liczne formy nanoplanktonu wapiennego wieku kampan-mastrycht. Wyznaczono poziomy nanoplanktonowe, określając wiek badanych osadów. W marglach bakulitowych, nazywanych też marglami z Węgierki, występujących w jednostce skolskiej, odnotowano podobny skład i charakter nanoplanktonu wapiennego jak w szarych marglach typu frydeckiego występujących w jednostce podśląskiej w zachodniej części Karpat. W badanych osadach jednostki podśląskiej nie stwierdzono ciągłego przejścia sedymentacyjnego między osadami mastrychtu i danu. Badania nanoplanktonu potwierdziły istnienie połączenia między strefą borealną i tetydzką na obszarze polskich Karpat zewnętrznych w kampanie i mastrychcie, o czym świadczy obecność w próbkach form nanoplanktonu uważanych za typowo borealne.

EN

In pelagic sediments of the Subsilesian Unit (Węglówka marls, Frydek-type marls, Żegocina marls and Rybie sandstones) and in the bakulit marls from the Skole Unit, and in marls from Bonarka in Silesian-Cracow Monocline many forms of calcareous nannoplankton of Campanian-Maastrichtian age were noted. Distinguishing of several nannoplankton assemblage zones allowed for more detailed time resolution of the studied sediments. Existing of the connection between the boreal and Tethyan realms in Polish Outher Carpathians during Campanian/Maastrichtian has been confirmed. Calcareous nannoplankton of the bakulit marls (Skole Unit) appeared similar to that from the Frydek-type marls (Subsilesian Unit). No continuous transition between sediments of the Maastrichtian and Danian within the studied Subsilesian Unit has been stated. Transition between Boreal and Tethyan realms on the Polish Outher Carpathians area, during Campanian and Maastrichtian age are confirmed.

18

Otwornice warstw cieszyńskich z obszaru Pogórza Cieszyńskiego (Karpaty zewnętrzne)

Szydło A.

Biuletyn Państwowego Instytutu Geologicznego

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2005

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nr 415

59-99

PL

W warstwach cieszyńskich odnotowano liczne otwornice bentoniczne wieku tyton-hoteryw. Generalnie ich liczebność i zróżnicowanie taksonomiczne zmniejszały się podczas depozycji tych osadów. Zubożenie zespołów otwornicowych było związane z transformacją geotektoniczną basenu karpackiego (cieszyńskiego) i ewolucją ówczesnych środowisk na przełomie jury i kredy. Analizy morfogrupowa i tafofacjalna wykazały, iż basen ewoluował od marginalnego i szelfowego zbiornika do otwartego basenu morskiego. Proces ten udokumentowała sukcesja ośmiu zespołów otwornicowych. Początkowo dominowały w nich wapienne otwornice bentoniczne znane z szelfowych i pararafowych środowisk basenów epikontynentalnych i morskich. Na przełomie jury i kredy zostały one wyparte przez głębokomorskie otwornice krzemionkowe. Pierwsza grupa wapiennych otwornic miała charakter allochtoniczny i była związana z końcową fazą regresji morza. Odmienna autochtoniczna mikrofauna pojawiła się z początkiem cyklu regresywno-transgresywnego. W tym czasie, przy nadal utrzymującym się niskim poziomie morza, doszło do wyraźnego pogłębienia zbiornika cieszyńskiego. Następstwo omawianych zespołów otwornic określa przynależność paleobiogeograficzną badanego fragmentu zbiornika karpackiego, który stał się integralną częścią oceanu tetydzkiego już we wczesnej kredzie.

EN

Numerous benthic foraminifers are noted in the Cieszyn Beds. Generally their number and taxonomic variability decreased during the sedimentation of these deposits. The impoverishment of foraminiferal assemblages, which corresponded with geotectonic transformation of the Carpathian (Cieszyn) Basin and evolution of the contemporary environments was noted at the turn of Jurassic-Cretaceous. Morphogroup and taphofacial analyses suggest that this basin evolved from narrow, shelf basin into open marine basin. Succession of foraminiferal assemblages has evidenced this process. At the beginning these assemblages contained calcareous benthic forms, which were known from shelf and para-reef environments of epicontinental and marine basins. At the Jurassic-Cretaceous boundary these ones were replaced by deep-water siliceous foraminifers. The first group of the mentioned foraminifers comprised mainly allochthonous forms, which occurred at the end of the regression of the sea. Autochthonous microfauna, al-though differing, appeared at the beginning of transgression cycle. At this time the basin was deepening while a level of the sea was as low as before. The sequence of the studied foraminiferal assemblages is related to paleobiogeographical position of the Cieszyn Basin, which finally became an integral part of the Tethyan bioprovince at the Early Cretaceous.