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1

New data on the age and stratigraphic relationships of the Czajakowa Radiolarite Formation in the Pieniny Klippen Belt (Carpathians) based on the radiolarian biostratigraphy in the stratotype section

Bąk M., Chodacka S., Bąk K., Okoński S.

Acta Geologica Polonica

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2018

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Vol. 68, no. 1

1--20

EN

The radiolarian biostratigraphy of the Middle–Upper Jurassic pelagic siliceous sediments (Czajakowa Radiolarite Formation) in the Niedzica succession of the Pieniny Klippen Belt (Carpathians) is interpreted in terms of their age in a stratotype section, and facies equivalents in other tectonic-facies units of this region. The siliceous sediments are represented by radiolarian cherts and silicified limestones which are underlain and overlain by red nodular limestones, equivalents of the Rosso Ammonitico facies. The radiolarian association includes thirty-seven taxa belonging to twenty one genera which represent the Northern Tethyan Palaeogeographic Province. Key radiolarians recorded provide a means of correlation with zonation schemes based on Unitary Associations defined for the Jurassic Tethyan sediments. The age of the Czajakowa Radiolarite Formation in the stratotype section is determined as U.A.Z.9 to U.A.Z.11 corresponding to middle Oxfordian up to Kimmeridgian. Comparison of radiolarian biozones from the stratotype section with other facial equivalent sections in the Pieniny Klippen Belt reveals a significant diachronism for both the lower and the upper limits of the Jurassic pelagic siliceous facies.

2

Three-dimensional imaging of the Jurassic radiolarian Protunuma ? ochiensis Matsuoka : an experimental study using high-resolution X-ray micro-computed tomography

Ishida N., Kishimoto N., Matsuoka A., Kimoto K., Kurihara T., Yoshino T.

Volumina Jurassica

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2015

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Vol. 13, no. 1

77--82

EN

To evaluate the utility of high-resolution micro-computed tomography (micro-CT) in observing radiolarian fossils, we examined the skeleton of the Jurassic radiolarian fossil Protunuma ? ochiensis Matsuoka using a micro-CT device. Although this species is a closed Nassellarian with a thick exterior wall, important taxonomic characters on the interior and exterior of the shell were represented almost perfectly in the acquired three-dimensional computer graphic images. These characters include those documented in the original description, such as the height and width of the skeleton, the outline, the number of segments, the pore arrangement and other features. In addition, the structure of the initial spicule of this species was revealed newly. An enlarged plaster radiolarian model printed using the laminated modelling method was useful for detailed observation. Nondestructive omnidirectional observation is an advantage of this method, which is not possible with scanning electron microscopy or optical microscopic investigations. Micro-CT technology would become an effective observational tool for radiolarian studies in the near future.

3

Rekonstrukcje paleotemperatur w strefie Frontu Polarnego Oceanu Południowego (sektor atlantycki) na podstawie środkowo-górnoplejstoceńskich promienic z odwiertu ODP Leg 177 Site 1091

Kotrys B.

Przegląd Geologiczny

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2014

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Vol. 62, nr 9

448--455

EN

Quantitative analysis of radiolarian assemblages, carried out at the Ocean Drilling Program (ODP) Leg 177 Site 1091 (Atlantic sector of the Southern Ocean), provides a well-established summer sea surface temperature (SSST) record from the Polar Front Zone extending back into the Middle Pleistocene at orbital- -submillennial resolution. In order to estimate the SSST, the Imbrie & Kipp method (IKM) and the artificial neural network (ANN) were applied. The SSST records derived from the IKM and ANN display close similarities in paleotemperature fluctuations, amplitudes and absolute values. The ANN-derived SSST estimations display a pattern of slightly more distinct warm events that is closest to the records obtained from EDC (EPICA Dome C) ice cores and ODP Site 1090. The warm events indicate a distinct shift in the extent of the Southern Ocean cold water sphere that must have affected the ocean–atmosphere–ice field interactions and the configuration of high-latitude wind fields. Consistently with the global trend of paleotemperature fluctuation, the SSST record is marked by a distinct shift from low to high glacial/interglacial variability around Termination V. Prior to Termination V, the SSST displays coldest values and low variability. It points to a distinct expansion of the Southern Ocean cold water masses and positional changes of hydrographical fronts during most of the lower Middle Pleistocene.

4

Foraminiferal and radiolarian biostratigraphy of the youngest (Late Albian through Late Cenomanian) sediments of the Tatra massif, Central Western Carpathians

Bąk K., Bąk M.

Acta Geologica Polonica

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2013

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Vol. 63, no. 2

223--237

EN

The foraminiferal and radiolarian biostratigraphy of selected sections of the Zabijak Formation, the youngest sediments of the Tatra massif (Central Western Carpathians), have been studied. Benthic foraminifers, mainly agglutinated species, occur abundantly and continuously throughout the studied succession, while planktic foraminifers are generally sparse. Five planktic and two benthic foraminiferal zones have been recognized. The marly part of the Zabijak Formation comprises the Pseudothalmanninella ticinensis (Upper Albian) through the Rotalipora cushmani (Upper Cenomanian) planktic foraminiferal zones, and the Haplophragmoides nonioninoides and Bulbobaculites problematicus benthic foraminiferal zones. The radiolarians were recognized exclusively in the Lower Cenomanian part of the formation.

5

Radiolarian and agglutinated foraminiferal biostratigraphy of the Paleogene deep-water deposits on the northern margin of the Carpathian Tethys (Skole Unit)

Rajchel J. M., Barwicz-Piskorz W.

Geological Quarterly

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2012

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Vol. 56, No 1

1-24

EN

Radiolarian and agglutinated foraminiferal fauna within upper deposits of the Skole Unit of the Polish Flysch Outer Carpathians occur in the Variegated Shale and Hieroglyphic formations of Paleocene and Eocene age. About 70 radiolarian and 50 foraminiferal species have been identified and their stratigraphic distribution determined using both regional and local biozonations. Five radiolarian zones: the Bekoma bidartensis Interval Zone, the Buryella clinata Interval Zone, the Phormocyrtis striata striata Interval Zone, the Theocotyle cryptocephala Interval Zone and the Dictyoprora mongolfieri Interval Zone in the lower Eocene and in the lower part of the middle Eocene have been distinguished. In the upper part of the middle Eocene and in the uper Eocene the abundance of radiolarians decreases and their age assignment has not been possible. Five foraminiferal zones have been distinguished and correlated with radiolarian zones based on co-occurrence of both Protista groups in the deposits investigated. These are: the Rzehakina fissistomata Zone, the Saccamminoides carpathicus Zone, the Reticulophragmium amplectens Zone, the Ammodiscus latus Zone and the Cyclammina rotundidorsata Zone covering the time span from upper Paleocene to upper Eocene.

6

Late Ladinian radiolarians from the Tahtalidag Nappe of the Antalya nappes, SW Turkey : remarks on the late Middle and Late Triassic evolution of the Tahtalidag Nappe

Tekin U., Sonmez I.

Acta Geologica Polonica

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2010

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Vol. 60, no. 2

199-217

EN

The late Ladinian to Late Triassic succession of the Tahtalidag (upper) Nappe of the Antalya nappes was studied in the Egregindere section, north of the city of Antalya, SW Turkey. The chert bands in the central part of the section have yielded poorly to moderately preserved radiolarians documenting the Late Ladinian Muelleritortis firma and Muelleritortis cochleata radiolarian zones. Based on the Egregindere succession, a major deepening event, evidenced by radiolarian cherts, took place between the middle and late Late Ladinian. The Late Triassic thick-bedded neritic limestones represent a shallowing-upward sequence, which formed as a result of the horst-like rising of the Tahtalidag Nappe during the Late Triassic block faulting. Fifty-nine radiolarian taxa have been determined from the Upper Ladinian of the Egregindere section. One species (Muelleritortis elegans) and two subspecies (Muelleritortis firma equispinosa and Muelleritortis firma globosa) are described as new.

7

Revised radiolarian zonation for the entire Jurassic in the western Pacific and Japan

Matsuoka A.

Volumina Jurassica

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2006

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Vol. 4, no. 1

183-184

EN

A radiolarian zonal scheme for the entire Jurassic in Japan was proposed by Matsuoka and Yao (1986) on the basis of radiolarian biostratigraphic research on several continuous sections in the Japanese Islands. The zonal scheme was partly modified by applying the results from deep sea cores obtained in the ODP Leg 129 cruise (Matsuoka 1992). The Jurassic zones composed of the Parahsuum simplum Zone (JR1), Trillus elkhornensis Zone (JR2), Laxtorum(?) jurassicum Zone (JR3), Tricolocapsa plicarum Zone (JR4), Tricolocapsa conexa Zone (JR5), Stylocapsa(?) spiralis Zone (JR6), Hsuum maxwelli Zone (JR7), Loopus primitivus Zone (JR8), and Pseudodictyomitra carpatica Zone (KR1), in ascending order, have been established by combining the results from land sections and ODP materials (Matsuoka 1995). The zonation is widely utilized for the dating of marine sequences in Japan and Asian countries. The accumulation of new data in the last decade requires a further revision of the zonation and age assignment. The major modifications are as follows: The Bipedis horiae Zone (JR0) is newly proposed below the Parahsuum simplum Zone (JR1). The base of the Bipedis horiae Zone (JR0) is defined by the first appearance of Bipedis horiae Sugiyama and corresponds roughly to the Triassic (Rhaetian)/Jurassic (Hettangian) boundary. The base of the Parahsuum simplum Zone is dated as Middle Sinemurian. The Tricolocapsa plicarum Zone (JR4), Tricolocapsa conexa Zone (JR5), and Stylocapsa(?) spiralis Zone (JR6) are replaced by Striatojaponicapsa plicarum Zone (JR4), Striatojaponicapsa conexa Zone (JR5), and Kilinora spiralis Zone (JR6), respectively, in accordance to the change of generic assignment of zone-diagnostic species. The base of the Pseudodictyomitra carpatica Zone (KR1) is dated as Early Tithonian based on the occurrence of the zone-diagnostic species from the Lower Tithonian of the Solnhofen area, Germany (Zügel 1995).

8

Feeding behavior of Jurassic radiolarians inferred from comparison in skeletal morphology with laboratory cultured radiolarians

Matsuoka A.

Volumina Jurassica

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2006

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Vol. 4, no. 1

239-240

EN

Living radiolarian research provides us with fundamental data for feeding behavior of radiolarians. Detailed observations of a variety in feeding behavior of laboratory cultured radiolarian specimens make it possible to understand the relationship between skeletal morphology and feeding behavior. This work focuses on the application of living radiolarian research to clarifying feeding behavior of Jurassic radiolarians, leading to reconstruct marine eco-system in the Jurassic oceans. Four types of feeding strategy well correspond to skeletal morphology in extant radiolarian taxa. High diversity of radiolarian skeletal morphology is partly related to having a variation in feeding strategies. The wide variation in feeding behavior means that radiolarians occupy several kinds of ecological niches in marine environments. We can infer feeding behavior of extinct radiolarian group based on their skeletal morphology. Once we recognize the role of radiolarians in food web in the modern ocean environments, we can apply it to reconstruct marine eco-system in the Jurassic time. Fluctuation in morphological diversity of radiolarian skeletons is well documented in fossil records. This fluctuation can be interpreted as change in the number of ecological niches in the marine eco-system through time. Jurassic radiolarians include most types of basic skeletal morphology of extant radiolarians except for colonial radiolarians. Extant Eucyrtidium, Pterocorys, Lipmanella and Spirocyrtis are model taxa for multi-segmented nassellarians such as Jurassic Archaeodictyomitra, Hsuum, Parahsuum, and others. Extant Lithomelissa and Pseudocubus are probably analogous to Jurassic small nassellarians like cryptocephalic and cryptothoracic taxa. Spherical and discoidal spumellarians are common in both recent and Jurassic radiolarian assemblages. Assuming that skeletal morphology indicates their feeding strategy then at least three types of feeding behavior were developed in the Jurassic time. The presence of radiolarian skeletal morphology suggests that prey of radiolarians also existed in a water column where radiolarians dwelled. The resemblance between modern and Jurassic radiolarian skeletons indicates that the marine eco-system in the present and Jurassic times is probably similar to each other in terms of the nature (size and mobility) of prey.

9

High resolution microfossil, microfacies and palynofacies studies as the only method in recognition of the Jurassic and Cretaceous "black shales" in a strongly tectonised section of the Czorsztyn Succession, Pieniny Klippen Belt, Poland

Bąk K., Barski M., Bąk M.

Studia Geologica Polonica

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2005

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Vol. 124

171-198

EN

Combined stratigraphic studies based on foraminifers, radiolarians and palynomorphs together with microfacies and palynofacies characteristics allowed us to separate the Lower Turonian sediments corresponding to the Cenomanian/Turonian boundary event from the Lower-Middle Jurassic black facies in a strongly tectonised section of the Czorsztyn Succession in the Pieniny Klippen Belt, Poland. The studied section, located at Trawne creek, includes tectonised incompetent series of black marly facies and pink, cherry-red marls and marly limestones. The Cenomanian/Turonian boundary event deposits (ca. 0.5 m thick) belong to the upper part of the Altana Shale Bed of the Jaworki Formation with uncertain transition to the pelagic pink and cherry-red marly limestones and marls. Both facies represent the Helvetoglobotruncana helvetica planktonic foraminiferal Zone (Lower-Middle Turonian). The other black facies in the studied section include dark-grey marly shales with dark-grey calcareous mudstone (ca. 1.5 m of total thickness). These sediments most likely belong to the Skrzypny Shale Formation. This is documented by the filament-radiolarian microfacies, dinocyst and radiolarian stratigraphic data. An Early Bajocian age was determined only for one thin package of dark-grey shale. Other packages of black facies include long-ranging dinocyst taxa of Late Pliens- bachian-Early Bathonian age. Following the earlier stratigraphic data for the Skrzypny Shale Formation (Middle Aalenian-Lower Bajocian), based on ammonite fauna, it may be suggested that a part of these black facies might represent the underlying lithostratigraphic unit, the Krempachy Marl Formation, or its transition to the Skrzypny Shale Formation. Pelagic cherry-red marls and marly limestones which in most cases are in tectonic contact with the black facies are here also strongly tectonised. They represent different, non-continuous stratigraphic horizons of the Lower-Middle Turonian and the Lower Campanian.

10

Stratigraphical and ecological significance of Early Eocene radiolarians from the Subsilesian Series, Polish Flysch Carpathians

Bąk M., Barwicz-Piskorz W.

Annales Societatis Geologorum Poloniae

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2005

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Vol. 75, No 2

139-139

EN

Variegated shales in the Early Eocene hemipelagic deposits of the Subsilesian series, Polish part of the Western Carpathians, have yielded rich siliceous microfossils comprising abundant radiolarians and rare diatoms. Forty-three radiolarian taxa have been recognised. One new radiolarian species, Amphisphaera subsilesianensis n. sp. was described. The assemblage represents the Phormocyrtis striata striata radiolarian Zone of the tropical oceans. The deposits investigated have also yielded abundant agglutinated foraminifera which correlate with the lower Eocene Saccamminoides carpathicus foraminiferal Zone. The radiolarian assemblage comprises a low content of taxa characterising cool, oligotrophic water masses which also occur in the upper Paleocene deposits of the Subsilesian series. Most part of the assemblage is represented by abundant radiolarian species characteristic of tropical domain, which may indicate the incursion of warm water masses into the Subsilesian Basin during the Early Eocene Climatic Optimum Period.

PL

Radiolarie eoceńskie z polskich Karpat fliszowych są stosunkowo słabo poznane. Istnieje tylko kilka prac dotyczących tych mikroskamieniałości z eocenu jednostki skolskiej (Bąk, 1995; Bąk et al., 1997; Rajchel et al., 1999). Prezentowany zespół radiolarii pochodzi z utworów dolnego eocenu jednostki podśląskiej, odsłaniających się w potoku Czerwin, w obrębie okna tektonicznego Wiśniowej (Fig. 1A, B). W odsłonięciu widoczne są utwory górnokredowych margli z Węglówki oraz paleogeńskich piaskowców z Czerwina, oraz zielonych i pstrych łupków (Fig. 2). Radiolarie zostały znalezione w zielonkawych łupkach ilastych należących do serii łupków pstrych, ponad pierwszą odsłaniającą się w profilu wkładką bentonitu (Fig. 1C). Badany zespół radiolarii obejmuje 43 gatunki należące do czterech rodzin z rzędu Nassellaria (Trissocyclidae, Arthostrobiidae, Pterocorythidae i Eucyrtidiidae) i do pięciu rodzin z rządu Spumellaria (Actinommidae, Phacodiscidae, Sponguridae, Spongodiscidae i Porodiscidae) (Figs 3-6). Wyróżniono także nowy gatunek - Amphisphaera subsilesianensis n. sp. (Fig. 3G-I). Na podstawie obecności wielu charakterystycznych gatunków promienic jak: Calocycloma ampulla (Ehrenberg), Buryella clinata Foreman, Phormocyrtis striata striata Brandt, Lychnocanium bellum (Clark & Campbell), L. auxilla Foreman, L. babylonis (Clark & Campbell), Amphisphaera minor (Clark & Campbell), Amphisphaera coronata (Ehrenberg), badany zespół zaliczono do zony radiolariowej Phormocyrtis striata striata, wyróżnionej przez Riedel & Sanfilippo (1987) dla regionów tropikalnych. Współwystępowanie zespołów otwornic aglutynujących wraz z radiolariami umożliwiło korelację tego poziomu radiolariowego z poziomem otwornicowym Saccamminoides carpathicus (Geroch & Nowak, 1984). Opisany zespół radiolarii wskazuje wyraźnie na ingresję ciepłych wód powierzchniowych do basenu podśląskiego we wczesnym eocenie, w których mogły żyć gatunki tropikalne i subtropikalne. Podobne zespoły taksonów występują w utworach jednostki skolskiej należących do tych samych poziomów biostratygraficznych (Bąk et al., 1997). Może to wskazywać na zmianę termiki wód oceanicznych na skalę regionalną, która mogła być związana z wczesnoeoceńskim optimum klimatycznym.

11

Calpionellid and nannoconid stratigraphy and microfacies at the Tithonian-Berriasian boundary in the Sierra del Infierno (western Cuba)

Pszczółkowski A., Delgado D. G., González S. G.

Annales Societatis Geologorum Poloniae

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2005

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Vol. 75, No. 1

1--16

EN

The radiolarian and calpionellid microfacies are characteristic for the latest Tithonian–Early Berriasian limestones of the Guasasa Formation in the Sierra del Infierno, western Cuba. The limestones of the uppermost part of the El Americano Memberbelongto the Late Tithonian Crassicollaria intermedia Subzone, Crassicollaria Standard Zone, and to the basal part of the Early Berriasian Calpionella alpina Subzone. The lower part of the Tumbadero Member is assigned to the C. alpina Subzone of the Calpionella Standard Zone. A heteromorph ammonite assemblage (Protancyloceras-Vinalesites) crosses the Crassicollaria/Calpionella Zones boundary. The studied limestones belong to three nannoconid assemblages of latest Tithonian–Early Berriasian age assigned to Nannoconus wintereri Subzone, N. steinmannii minor Subzone and N. steinmannii steinmannii Zone. Radiolarian taxa identified in thin sections are consistent with the lower part of D2 radiolarian zone from Western Tethys. The investigated deposits have been probably accumulated in the dysaerobic zone. At the Tithonian–Berriasian (J/K) boundary, dysaerobic to anaerobic conditions could be widespread in the deeper waters of the northwestern Proto-Caribbean basin.

PL

W niniejszej pracy zostały zbadane dwa profile obejmujące wapienie najwyższego tytonu i dolnego beriasu w Sierra del Infierno, na zachód od Vifiales w zachodniej części Kuby (Fig. 1A-C). Wapienie najwyższej części ogniwa El Americano formacji Guasasa (Tab. 1) należą do podpoziomu Crassicollaria intermedia poziomu standardowego Crassicollaria (górny tyton) i najniższej części podpoziomu Calpionella alpina (dolny berias) poziomu standardowego Calpionella (Fig. 2, 3). Dolna część ogniwa Tumbadero została zaliczona do podpoziomu C. alpina. W wapieniach najwyższej części ogniwa El Americano (Fig. 4A) i dolnej części ogniwa Tumbadero (Fig. 4B) charakterystyczne są mikrofacje kalpionellidowa (Fig. 5A) i radiolariowa (Fig. 6A). Pelmikrosparyty (Fig. 5B) i laminowane biomikryty (Fig. 6B) również są spotykane w dolnym beriasie. Kalpionellidy (Fig. 7A-I) są reprezentowane przez pojedyncze okazy do bardzo licznych zespołów (Tab. 2); zwykle są one słabo zachowane. Jest to już wcześniej opisana cecha kalpionellidów obecnych w wapieniach późnego tytonu i beriasu sukcesji Sierra de los Organos (Pop, 1976). Badane wapienie zawierają również nannokonidy (Fig. 8, 9A-H) zaliczone tutaj do podpoziomów Nannoconus wintereri i N. steinmannii minor oraz do poziomu N. steinmannii steinmannii (Tab. 3). Granica ogniw El Americano i Tumbadero znajduje się w obrębie podpoziomu N. steinmannii minor. Radiolarie oznaczone w płytkach cienkich (Fig. 10A-J, 11) odpowiadają dolnej części poziomu radio-lariowego D2 ustalonego w formacji Maiolica zachodniej Tetydy (Jud, 1994). Niektóre rodzaje (Ristola, Mirifusus) są często spotykane w badanych profilach. Obecność juwenilnych amonitów rozwiniętych: Protancyloceras gr. hondense (Imlay) (Fig. 12A), Protancyloceras sp. i Vinalesites sp. (Fig. 12B) została stwierdzona w niektórych płytkach cienkich wykonanych z wapieni (Tab. 4). Zespół tych amonitów przekracza granicę poziomów kalpionellidowych Crassicollaria i Calpionella (Tab. 5). Szare, ciemnoszare i czarne wapienie najwyższej części ogniwa El Americano i dolnej części ogniwa Tumbadero zostały osadzone prawdopodobnie w strefie dysaerobowej, w której fauna bentosowa była bardzo nieliczna (Fig. 12C). Ławice wapieni zazwyczaj nie zawierają struktur wskazujących na intensywną działalność organizmów ryjących w osadzie. W pobliżu granicy tytonu i beriasu (J/K), warunki dysaerobowe (lub nawet anaerobowe) mogły być rozprzestrzenione w głębszych wodach północno-zachodniej części basenu Protokaraibskiego. Takie warunki wskazująna raczej słabą cyrkulację w głębszych wodach tego dosyć wąskiego w tym czasie basenu.

12

Pyrite framboids in pyritized Radiolarian skeletons (Mid-Cretaceous of the Pieniny Klippen Belt, Western Carpathians, Poland)

Szczepanik P., Sawłowicz Z., Bąk M.

Annales Societatis Geologorum Poloniae

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2004

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Vol. 74, No 1

35--41

EN

Well preserved pyritized radiolarian skeletons have been found within the grey-green Mid-Cretaceous (Upper Cenomanian) shales in the Pieniny Klippen Belt (Carpathians, Poland). The skeletons contain numerous pyrite framboids in different positions, in channels and inside the abdomen of cryptothoracic forms, but their genetic context is not known. They were formed as a result of the reaction between dissolved iron and sulphide originated from the bacterial sulphate reduction. Two sources of organic matter, "post mortem" in situ decaying organic matter of radiolaria and disseminated organic matter from the surrounding sediment could be available for this process. Pyrite found in the radiolarians probably originates from different processes. It is suggested that pyritization of the radiolarian skeletons took place in the water column whereas pyrite framboids in the skeleton's free spaces could have been formed later during the diagenesis of the sediment. However, their simultaneous formation in the water column or in the sediment cannot be excluded.

13

Radiolarian faunas from the Late Callovian and Early Oxfordian deposits of the Kraków-Wieluń Upland, South Poland

Smoleń J.

Annales Societatis Geologorum Poloniae

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2002

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Vol. 72, No 2

145-161

EN

This paper presents the result of research on radiolarian faunas from the Upper Callovian and Lower Oxfordian deposits of the Kraków-Wieluń Upland (South Poland). The studied material comes from boreholes Wodna 1, Trzebionka 2 and Trzebionka 3, and from outcrops at Górka near Trzebinia and Grojec. Two radiolarian assemblages, differing markedly in their species contents, I and II, have been identified. Assemblage I occurs in the Upper Callovian deposits. It has been found within Q. lamberti ammonitic Zone. In the number of specimens this association is dominated by the spherical, oval and conical forms of the Nassellaria group. Assemblage II is associated with the Lower Oxfordian deposits and it is characterised by the dominance of spongy radiolarians belonging to the Spumellaria group. Assemblage II has been found within Q. mariae and C. cordatum ammonitic zones. A correlation with the Tethyan radiolarian zones indicates that both assemblages can be assigned to U.A.Z. 8 (Late Callovian trough Early Oxfordian age). The radiolarians show features of Tethyan faunas which spread over epicontinental seas when communication with the Tethys Ocean opened. A change in the character of the radiolarian assemblage in the Lower Oxfordian suggests boreal influences as well as gradual shallowing of the basin.

14

Agglutinated foraminifera, radiolaria and trace fossils from Upper Cretaceous Deep-Water Variegated Shales at Trawne Stream, Grajcarek Unit, Pieniny Klippen Belt, Carpathians, Poland

Bąk K., Uchman A., Bąk M.

Bulletin of the Polish Academy of Sciences. Earth Sciences

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2000

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Vol. 48, nr 1

1-32

EN

The age and palaeoenvironment of the Upper Cretaceous non-calcareous variegated shales have been interpreted, based on the foraminiferal, radiolarian and trace fossil assemblages from the Malinowa Shale Formation of the Grajcarek Unit (Pieniny Klippen Belt, of Poland), exposed at Trawne Stream. The deposits represent the lower part of the Uvigerinammina jankoi Zone (Turonian-Coniacian), as based on the occurrence of foraminifers Uvigerinammina praejankoi Neagu and U. jankoi Majzon, and radiolaria Holocryptocanium barbui Dumitrica, H. tuberculatum Dumitrica, Praeconocaryomma universa Pessagno and P. lipmanae Pessagno. Predominance of non-calcareous shales with siliceous-walled agglutinated foraminifers and radiolaria as the only biotic components, and occurrence of trace fossils typical of the Nereites facies, indicate a deep-water marine palaeoenvironment, below the CCD. Energy of bottom-waters was low, except for rare episodes of diluted turbidite flows. Diversified foraminiferal benthic and trace fossil assemblages, abundant epi- and infaunal foraminiferal morphotypes, low values of foraminiferal dominance index, intense bioturbation of the shales, and well-developed tiering pattern of the trace fossils (including deep-tier ichnotaxa such as Zoophycos and Scolicia), indicate that the sediments were poor in organic matter and were deposited in highly oxygenated conditions. Changes in the sediment colouration (red and grey-green) are reflected in small changes within the foraminiferal benthos and trace fossil assemblages.

15

Early Oxfordian Radiolaria from Zalas quarry, Kraków Upland, South Poland

Górka H., Bąk M.

Annales Societatis Geologorum Poloniae

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2000

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Vol. 70, No. 2

165-179

EN

This paper presents preliminary research on radiolarian faunas from the Upper Jurassic deposits of the Kraków Upland (South Poland) carried at Zalas quarry. The systematic description of twenty-five species of Radiolaria from the lower Oxfordian deposits has been presented herein. The species belong to the orders Nassellaria (16 species) and Spumellaria (9 species). In number of specimens, the assemblage is dominated by spumellarians. The radiolarians show features of Boreal faunas, influenced by Tethyan realm. The assemblage has been correlated with cordatum ammonitic subzone (early Oxfordian).

PL

W pracy przedstawiono wstępne wyniki badań promienic (Radiolaria) z utworów górnej jury, prowadzonych na Wyżynie Krakowskiej w kamieniołomie w Zalasie. Przedstawiono opis systematyczny 25 gatunków promienic z dolnego oksfordu. Spośród opisanych form 16 reprezentuje rząd Nassellaria, a 9 należy do rzędu Spumellaria. Pod względem liczby okazów, w zespole przeważają przedstawiciele rzędu Spumellaria. Promienice reprezentują faunę borealną, która żyła w środowisku o znacznym wpływie morza tetydzkiego. Analizowany zespół promienic został skorelowany z podpoziomem amonitowym cordatum (wczesny oksford).