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1

Ichnological record of oxygenation changes in the Lower Cretaceous flysch deposits of the Silesian Unit, Polish Carpathians

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Uchman A.

Biuletyn Państwowego Instytutu Geologicznego

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2001

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tom nr 396

159-160

2

Paleogeographic characterization of the Early Cretaceous "Urgonian" carbonate platforms

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Fekete K. , Straka A.

Geology, Geophysics and Environment

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2014

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tom Vol. 40, no. 1

80--81

EN

The objective of the present paper is to show clues which are provided for understanding the development and paleogeographic significance of the Lower Cretaceous carbonate platform sequences in different localities. The results are based mainly on the study of previous works and also on the preliminary results from lithological sections investigated by authors. The Urgonian-type limestone represents a characteristic Barremian and Aptian shallow-water carbonate facies deposited along the northern Tethyan margin. The term Urgonien was established by A. d'Orbigny in 1847 for the reef limestones near Orgon (southern France). The facies encloses massive, light-coloured organodetrital limestones with foraminifers (Orbitolina) and transitional sediments - detrital or siliceous limestones. Among bioclasts, fragments of bivalves (rudists), corals, hydrozoans, bryozoans, small and large foraminifera (Palorbitolina lenticularis, Sabaudia minuta) and algae are the most characteristic constituens. In the Early Cretaceous, the opening of Alpine Tethys was completed and induced the development of carbonate platforms on its northern margin. Urgonian carbonate platforms in the Tethys have been widely studied (e.g. Arnaud & Arnaud-Vanneau 1991, Michalik 1994). Several deposition areas can be distinguished in the Western Carpathians, mainly: the Tatric "Urgonian" Platform (biohermal and lagoonal facies), source of the detritus transported to the Murań Limestone; and the Manin Urgonian Platform prograding into the Bela Unit during the Aptian. Debris from both platforms was transported into adjacent basins and deposited as allodapic accumulations (Misik 1990). The oldest hypothesis on the position of the neritic "Urgonian" Lower Cretaceous limestones of the Manin Unit consisting of Podhorie and Manin formations was summarized by Andrusov (1938). He considered the Manin Unit as an independent nappe unit. Later, based on lithostratigraphic and tectonic features, he characterized it as a succession of Central Carpathian affinity. However, its position and the tectonic style are close to Pieniny Klippen Belt structures (Andrusov 1938, Birkenmajer 1977). From the Urgonian-like facies, which occur in the Klippen Belt and the Peri-Klippen Belt we focused mainly on the Manin Unit in the area of the Strazovske vrchy Mts., the Nizna Unit (Nizna Limestone Formation) (Jozsa & Aubrecht 2008), Benatina Klippe (Schlogl et al. 2004) and also in the Haligovce Unit (Haligovce Limestone Formation), which is usually considered as an equivalent of the Manin Unit. In the Outer Carpathians, the Urgonian-type limestones occur exclusively as exotic pebbles in younger deposits. Urgonian facies in the Western Carpathians shows some different features in comparison with other areas in the Tethys realm; e.g. lack of oolitic and oncolitic limestones, small representation of typical lagoonal facies with miliolids and dasycladaceans. The "reef-tufa" cementation, fenestrae, evaporate minerals are also missing, bauxitization is unknown. They use to be affected by silicification (presence of cherts). Dolomitization is almost missing (Misik 1990).

3

Hydrocarbon generating potential and their migration versus the diagenetic changes in Upper Jurassic and Lower Cretaceous sediments in the Polish Lowlands

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Wołkowicz K. , Grotek I.

Volumina Jurassica

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2006

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tom Vol. 4, no. 1

261-262

EN

The material studied came from selected boreholes, mainly in the Mid-Polish Trough: Korabiewice PIG 1, Magnuszew IG 1, Narol PIG 1, Narol PIG 2, Oświno IG 1, Poddębice PIG 2, Strzelno IG 1 and Tomaszów Lubelski IG 1. In the Upper Jurassic section, marine carbonates predominate (e.g. Radlicz 1997). At the Jurassic/Cretaceous boundary, the basin shallowed substantially, and carbonate-sulphate deposits formed. During the subsequent stage of Lower Cretaceous sedimentation, carbonate and siliciclastic rocks were deposited (e.g. Marek 1997). The sediments underwent diagenetic processes influencing their reservoir properties. In the Upper Jurassic carbonate rocks, dissolution of many constituents, especially bioclasts, led to formation of numerous pores. Also heavy dolomitization enhanced their secondary porosity. Chemical compaction produced stylolite sutures, acting as possible migration ways for fluids. The reservoir properties were negatively affected by mechanical compaction and cementation, due to denser packing of grains and filling the pores with calcite and anhydrite. Diagenetic processes led to formation of rocks with various levels of porosity or very poorly permeable (<0.1mD). In the Lower Cretaceous strata, important results of decreased porosity are due to compaction and cementing. In siliciclastic rocks, grains were protected against destruction by compaction by their early diagenetic overgrowths of quartz and chlorite. In carbonates, the grains were similarly protected by calcite spar envelopes or micritic covers. While early cementation helped preserving primary porosity, late cementation led to blocking of the pores between grains and crystals. In arenites increased porosity was due to dissolution of unstable constituents, mainly feldspars. Through diagenesis, the Cretaceous sandstones obtained strongly porosity and permeable. The studied Upper Jurassic and Lower Cretaceous strata contain organic matter, mainly humus type, with poor hydrocarbon generating potential. The degree of their transformation indicates immature (Lower Cretaceous) or early (Upper Jurassic) hydrocarbon generating stageCretaceus deposits. (Figs 1, 2). Only the most changed Upper Jurassic rocks from the Poddębice PIG 2 borehole in their bottom part achieve the main stage of petroleum generation. Locally, they are enriched in organic carbon (>1.5% Corg), thus can be regarded as very poor or poor bedrock for oil generation. Upper Jurassic rock studied showed low maturity of organic matter to hydrocarbon generation, with limited migration potential. The Cretaceous strata analyzed contain organic matter at the immature stage. However, noteworthy is the presence of sandstones with high filtration properties.

4

Lower Cretaceous exotic intraplate basaltoid olistolith from Biała Woda, Pieniny Klippen Belt, Poland: geochemistry and provenance

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Birkenmajer K. , Lorenc M. W.

Studia Geologica Polonica

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2008

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tom Vol. 131

237-246

EN

Geochemical analysis of a basaltic olistolith, K-Ar dated at Lower Cretaceous, which occurs in Upper Cretaceous conglomerates (Jarmuta Formation) of the Pieniny Klippen Belt of Poland, points to trachybasalt field of intraplate basaltoids. The olistolith most probably derived from a volcanic structure located on the Czorsztyn Ridge - a lithospheric splinter of the North European Platform which, during Jurassic-Early Cretaceus, bordered the Pieniny Klippen Belt Basin from the north.

5

Foraminifera from the Late Jurassic and Early Cretaceous carbonate platform facies of the southern part of the Crimea Mountains, Southern Ukraine

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Krajewski M. , Olszewska B.

Annales Societatis Geologorum Poloniae

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2007

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tom Vol. 77, No 3

291-311

EN

Upper Jurassic and Lower Cretaceous deposits of the Crimea Peninsula are rich in microfossils frequently used for stratigraphic interpretations. In case of foraminifera, the research has been carried predomi- nantly on assemblages obtained by washing the rock samples. The present paper is based on investigations of thin sections from the more indurated sediments that seldom were objects of study. Its goal was to obtain additional information on age and environment of sediments studied. Over 250 thin sections from 16 surface outcrops yielded abundant foraminifera from which over fourty are described herein. Many foraminiferal species (e.g., Labirynthina mirabilis, Parurgonina caelinensis, Neokilianina rahonensis, Amijella amiji, Anchispirocyclina lusitanica) are stratigraphically significant and known from the Kimmeridgian-Tithonian of the Mediterranean Tethys. The Early Cretaceous fauna is represented by Protopeneroplis ultragranulata, Everticyclammina kelleri, Nautiloculina bronnimanni, Monsalevia salevensis, and Mayncina bulgarica. Generally, the investigated fauna is typical for paleoenvironment of the carbonate platform. Older (Kimmeridgian-Tithonian) assemblages represent the inner, and younger (Berriasian) outer parts of the platform. Palaeogeographic distribution of many species described from the studied area indicates their affiliation with cosmopolitan biota known from the north Tethyan shelf. Additionally, few calcareous cysts of Dinoflagellata have been identified and described.

6

Actinaraeopsis ventosiana, a new scleractinian species from the Lower Cretaceous of Provence (SE France)

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Morycowa E. , Masse J. P.

Annales Societatis Geologorum Poloniae

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2007

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tom Vol. 77, No 2

141-145

EN

Actinaraeopsis ventosiana is a new scleractinian coral species from the Lower Cretaceous shallow- water limestones of the Mont Ventoux (Provence, SE France). To date only two Late Jurassic species of this genus have been known, i.e. Actinaraeopsis araneola Roniewicz and A. exilis Roniewicz. The new species shows some similarity to the Jurassic species A. araneola, but differs in microstructure details and morphometric parameters.

PL

W pracy opisano nowy gatunek koralowca kolonijnego Actinaraeopsis ventosiana, pochodzącego z płytkowodnych wapieni górnobarremskich Prowansji (SE Francja). Dotychczas tylko dwa gatunki tego rodzaju są znane z jury górnej, A. araneola Roniewicz i A. exilis Roniewicz. Nowy gatunek Actinaraeopsis ventosiana wykazuje pewne podobieństwo do jurajskiego gatunku A. araneola, ale różni się od niego parametrami morfometrycznymi i szczegółami budowy mikrostrukturalnej szkieletu.

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A mixed assemblage of deep-sea and shelf trace fossils from the Lower Cretaceous (Valanginian) Kamchia Formation in the Troyan region, central Fore-Balkan, Bulgaria

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Uchman A. , Tchoumatchenco P.

Annales Societatis Geologorum Poloniae

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2003

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tom Vol. 73, No 1

27-34

EN

Trace fossils collected from the best outcrop of the Kamchia Formation have been analysed. There are thirteen ichnotaxa (Curvolithus simplex, Gyrochorte isp., ?Helminthoidichnites tenuis, Multina minima [second occurrence], Palaeophycus tubularis, ?Palaeophycus isp., Phycodes bilix, Phycosiphon incertum, Planolites cf. reinecki, Spongeliomorpha ?chevronensis, Squamodictyon tectiforme, Thalassinoides suevicus, Zoophycos isp.) representing different ethologic, toponomic and preservational types, and produced at different depths in the sediment. The ichnoassemblage contains a mixture of forms typical of flysch (Squamodictyon) and shelf deposits (Curvolithus, Gyrochorte). Probably, sediments of the Kamchia Formation were deposited in an offshore or deeper basin with storm deposition of sand beds and background marly sedimentation. It is possible that storm currents transported trace makers of the shelf trace fossils to the deeper sea. It is not excluded that the trace maker of Gyrochorte migrated to the deep-sea after the Jurassic. However, the simplest explanation is that the Kamchia ichnofauna represents an ecological transition between shelf and slope communities.

8

The Olcostephanus Level : an Upper Valanginian ammonoid mass-occurrence (Lowel Cretaceous, Northern Calcareous Alps, Austria)

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Lukeneder A.

Acta Geologica Polonica

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2004

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tom Vol. 54, no. 1

23-33

EN

The Early Cretaceous mass-occurrence of Olcostephanus (Olcostephanus) guebhardi morph. querolensis BULOT from the Late Valanginian Saynoceras verrucosum Zone of the KB1-A section, Ternberg Nappe, the Northern Calcareous Alps (Upper Austria) is described. This horizon, spanning an interval of almost 3 metres, is interpreted as a long-term accumulation from the water column combined with temporary redeposition from local submarine highs. The fauna of the Olcostephanus horizon is composed of nine genera and ten species. The Olcostephanus mass-occurrence represents a widespread phenomenon. It appears most commonly at oceanographic elevations where olcostephanid shells accumulated on the sea-floor during see-level highs.

9

Geochemical analysis for palaeoenvironmental interpretations : a case study of the English Wealden (Lower Cretaceous, south-east England)

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Akinlotan O.

Geological Quarterly

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2017

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tom Vol. 61, No. 1

227--238

EN

The elemental composition of terrigenous sediments is extremely important for interpreting the depositional conditions of sedimentary basins especially when traditional data are not available or insufficient. For the first time in the published literature, the elemental composition of the Lower Cretaceous Weald Basin (south-east England) is presented via X-ray fluorescence (XRF) and Spectral Gamma-ray (SGR) methods. The concentrations of Zr, Cr, Ni, Rb, and Sr in varying quantities suggest that the sediments may have been sourced from a stable craton while the enriched redox-sensitive elements such as Mo and Co confirm the presence of anoxic and reducing conditions at the sites of deposition. The spectral gamma-ray data show that the sandstone facies are more radioactive than the adjacent mudstone and shale and this trend is consistent with a freshwater origin. The higher quantity of thorium in relation to uranium indicates humid and hot palaeoclimatic conditions at the source areas that favoured intense weathering. The results of these analyses reinforce the importance of the geochemistry of sedimentary rocks as useful tools for understanding the depositional conditions of sedimentary basins.

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The Aptian Gura Râului conglomerates (Southern Carpathians) : remains of an extended subaqueous gravity flow deposit from the eastern flank of the Getic Nappe

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Ungureanu R. , Săsăran E. , Bucur I. I. , Mircescu C. V. , Ungureanu A. , Ungur C. G.

Geological Quarterly

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2019

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tom Vol. 63, No. 1

88--105

EN

The Getic Nappe belongs to the Central Dacides or Dacia Mega Unit. Gravity flow deposits were generated by the Lower Cretaceous overthrust and uplift of this unit over the External Dacides. In the Piatra Craiului Syncline (part of the Getic Nappe), such detrital deposits are represented by the Aptian conglomerates and the uppermost Albian-Cenomanian conglomerates. Part of the infill of the syncline consists of a thick pile of NW-SE oriented conglomerates. Sedimentological study documents the presence of an association which consists of three distinct facies types, represented by: massive conglomerates; alternating conglomerates, sandstones and microconglomerates; and fining- and coarsening-upwards conglomerates. These deposits were accumulated through a series of debris flows, and hyperconcentrated or concentrated flows. The entire assemblage represents a complex routing system within submarine channels, an interpretation made by interpreting facies associations, palaeoflow directions and clast fabrics. A large part of this succession was removed by post-Albian erosion. Thus, the interpretation of the depositional system could be as a series of feeder channels or the submarine sector of a fan-delta system representing a foreland basin fill.

11

The palynofacies pattern for the Lower Cretaceous of central Poland

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Leszczyński K. , Waksmundzka M.

Geological Quarterly

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2013

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tom Vol. 57, No. 1

101–-112

EN

Sedimentary environments and palynofacies were identified in the Lower Cretaceous of central Poland. The study was based on lithological observations, sedimentological logging and palynological investigations in the following boreholes: Poddębice PIG2, Koło IG3 and IG4, Wągrowiec IG1, Sarnów IG1, Ciechocinek IG3, Mszczonów IG1, Korabiewice PIG1, Człuchów IG2, Klosnowo IG1 and Tuchola IG1. Palynological observations were correlated with sedimentological, lithofacies and paleogeographical data. Sedimentary environments and palynofacies were analysed in the vertical section, and spatially in different areas: in the central basin area, in the carbonate-clastic deposition zone, in the transitional zone (deltaic sedimentation) and in a zone of an active salt pillow. The following sedimentary environments were identified in the Lower Cretaceous: upper shoreface and lower-middle shoreface with transitions to an offshore-open marine shelf, delta (?delta front) passing up into distributary channel fills on a delta plain, presumed barrier and shallow-marine embayment, lagoon and shallow carbonate-siliciclastic shelf. In case of the absence of diagnostic features for exact determination of sedimentary environments, the environments were defined as generally marine or transitional (probably deltaic). A maximum flooding surface has been identified in the Poddębice PIG2 section, represented by a thin dark-grey marl bed which seems to be dated at the Berriasian/Lower Valanginian transition. The relationships between sedimentary environments and the characteristics of the palynofacies spectrum were determined, and a palynofacies pattern for the Lower Cretaceous of central Poland was proposed in a tabular form.

12

Facies of the Upper Jurassic–Lower Cretaceous deposits from the southern part of the Carpathian Foredeep basement in the Kraków–Rzeszów area (southern Poland)

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Krajewski M. , Matyszkiewicz J. , Król K. , Olszewska B.

Annales Societatis Geologorum Poloniae

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2011

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tom Vol. 81, No 3

269-290

EN

A comparative sedimentological analysis of the Upper Jurassic–Lower Cretaceous deposits carried out on drill-cores from the southern part of the Carpathian Foredeep allowed us to distinguish thirteen main microfacies types. The results of microfacies analyses and stratigraphical data made it possible to propose a lithological subdivision of the southern part of the Upper Jurassic and Lower Cretaceous sediments of the Carpathian Foredeep basement between Kraków and Rzeszów. In the analysed wells, three main sedimentary complexes were distinguished, embracing the following intervals: (i) Callovian–Oxfordian, (ii) Kimmeridgian and (iii) Tithonian– Berriasian–Valanginian. The Oxfordian, Kimmeridgian and Tithonian deposits represent the outer – mid homoclinal ramp facies, whereas the Berriasian and Valanginian deposits belong to the inner homoclinal ramp facies. Complexes of microbial-sponge reefs, with a distinct relief, could be recognised in the Upper Oxfordian sediments only. The development of these buildups took place in a basin typified by diversified morphology, determined by the block-type structure of the Palaeozoic basement and synsedimentary tectonics, which brought about substantial variability in thickness of the Oxfordian sediments. At the end of the Oxfordian, large complexes of the reef facies were replaced mainly by microbial-sponge and microbial-coral biostromes developed during the Kimmeridgian and Tithonian. In the principal part of the studied area (except the western part of the described fragment of the Carpathian Foredeep; Kraków area) during the Kimmeridgian, Tithonian, Berriasian and Valanginian, sedimentation occurred in a basin typified by homogeneous morphology, which resulted in a wide extent and comparable thicknesses of the distinguished facies types. In the studied sections, indications of partial or complete dolomitization were observed in a large part of the sediments. Four generations of dolomite document a complex diagenetic history with multiple episodes of dolomite formation: from early diagenetic environment to late burial conditions.

13

Facies of the Upper Jurassic–Lower Cretaceous sediments in the basement of the Carpathian Foredeep (western Ukraine)

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Krajewski M. , Król K. , Olszewska B. , Felisiak I. , Skwarczek M.

Annales Societatis Geologorum Poloniae

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2011

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tom Vol. 81, No 3

291-307

EN

The Upper Jurassic–Lower Cretaceous carbonate sediments developed in a narrow, Ukrainian part of the basement of the Carpathian Foredeep show high facies diversity. Based upon thin section studies, the authors identified eleven principal microfacies varieties. Three main stages of development of carbonate platform were distinguished: (i) Oxfordian–Early Kimmeridgian, (ii) Kimmeridgian–Tithonian, and (iii) Berriasian–Valanginian. The Oxfordian sediments are rather thin and represent both the outer and inner, distally steepened ramp facies. In the Late Kimmeridgian and, mainly, in the Tithonian, the intensive growth of rimmed platform took place with distinct zones of peritidal, margin barrier and platform slope, bearing calciturbidite facies. Development of the rimmed platform was controlled by synsedimentary tectonic movements along faults rejuvenated southwest of the Holy Cross Mts. Fault Zone. In the Berriasian–Valanginian, the dominant process was sedimentation onto not-rimmed platform controlled by small sea-level changes. Both the facies development and literature data indicate that the Late Jurassic sedimentation in the Ukrainian part of the Carpathian Foredeep basement shows considerable differences in comparison to that of the Polish part. In the studied successions, large Oxfordian microbial-siliceous sponge reef complexes, known from the Polish part of the Carpathian Foredeep basement and other areas in Europe, were rare. In the study area carbonate buildups were encountered mainly in the intervals representing the Upper Kimmeridgian–Tithonian where small, microbial-sponge and microbial-coral biostromes or patch-reefs were formed. Their growth was presumably restricted to a narrow zone of the upper slope, close to ooidal-bioclastic margin platform facies. In the Polish part of the Carpathian Foredeep basement, the Late Jurassic sedimentation took place on a vast, homoclinal ramp while in the Ukrainian part it proceeded on a narrow, distally steepened ramp and rimmed platform with distinct marginal platform barrier. Similar platform facies distribution in both regions appeared mainly in the Early Cretaceous, although with some stratigraphical differences. The facies distribution of the Upper Jurassic sediments was closely controlled by the block structure of the basement and by orientation of the main, transcontinental Holy Cross Mts. Fault Zone, which supports the opinion on its activity in the Mesozoic era. The Ukrainian part of the Carpathian Foredeep basement located over the Palaeozoic Kokhanivka Block, between the Krakovets and Holy Cross fault zones, includes predominantly the slope, marginal and inner platform facies. Facies observed over the Palaeozoic Rava Ruska Block (south-western part of the East-European Platform), between the Holy Cross and Rava Ruska fault zones, represents mainly the inner platform and the peri-shore deposits.

14

Provenance of Lower Cretaceous deposits of the western part of the Silesian Nappe in Poland (Outer Carpathians): evidence from geochemistry

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Wójcik-Tabol P. , Ślączka A.

Annales Societatis Geologorum Poloniae

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2013

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tom Vol. 83, No. 2

113–-132

EN

The turbiditic to hemipelagic, fine-grained deposits of the Hradiště Formation (Hauterivian, 132 Ma) to the Lhoty Formation (Albian–Cenomanian, 99 Ma) in the western part of the Silesian Nappe (Polish Outer Car- pathians) were studied mineralogically and geochemically to determine if the main factors controlling the chemistry of the sedimentary material can be attributed to provenance, or to post-depositional processes. A high degree of weathering of the source rocks is indicated by the chemical index of alteration (CIA) that varies from 75.98 to 89.86, and Th/U ratios (~4 with outliers at 1.85 and >6). The cooccurrence of rounded and unabraded grains of zircon and rutile, the enrichment in Zr and Hf, as well as the high Zr/Sc ratios suggest that the Hradiště and Veřovice Formations contain recycled material. Plots of La/Th versus Hf and Th against Sc show that samples occur in the field of felsic and mixed felsic/basic sources. On a ternary La–Th–Sc diagram, all of the sediments studied are referable to the continental island-arc field. The European Plate, as an alimentary area, has a mosaic structure consisting of Cadomian and Variscan elements. The Proto-Silesian Ridge was detached from the continent, because of rifting. Therefore, it could have corresponded to a continental island arc. The concentrations of Fe and trace metals (e.g., Mo, Au, Cu) in the Veřovice Formation and silica and potassium additions to the Veřovice and Lhoty Formations, as well as the fractionation of REE, and Nb, Ta, Zr, Hf, and Y can be explained by the action of basinal brines. The fluids were of hydrothermal origin and/or were released, owing to the dewatering of clay minerals. Diagenetic processes could have exerted a greater influence on sedimentary rock chemistry than the provenance and sedimentary processes. A distinction between primary, terrigenous elements and those changed diagenetically is necessary for the reliable determination of provenance.

15

Biostratigraphy and palaeoecology of the Dalichai Formation (Lower Cretaceous) based on calcareous nannofossils from the western Alborz Mountains (north-west Iran)

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Shiri R. , Hadavi F.

Geological Quarterly

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2021

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tom Vol. 65, No. 4

art. no. 53

EN

We describe the biostratigraphy and palaeoecology of the Dalichai Formation based on calcareous nannofossils from the Guydagh section in the western Alborz Mountains, north-west Iran. The nannofossils are moderately to well-preserved, and 25 species belonging to 8 genera have been distinguished, representing the Early Berriasian to Late Hauterivian ages according to the CC1-CC4b biozones of Sissingh (1977). The recorded nannofossils are generally Tethyan and cosmopolitan, while the record of Nannoconus inornatus, a Boreal species, at the top of the section reflects the water mass connection between the Boreal and Tethyan domains during the Late Hauterivian. The records of Nannoconus spp., Watznaueria spp., and Rhagodiscus asper show that the sedi mentary basin of the Dalichai Formation was located at low lati tudes of the Tethyan realm with warm surface waters. Palaeoecologically, the findings represent a marine transgression and increasing depth, and the palaeoenvironmental conditions change from low-high mesotrophic (shown by the dominance of W. britannica) to oligotrophic (from the dominance of nannoconids), r- to K-strategy of life (from the dominance of nannoconids), and became increasingly stable (shown by the reduction of W. britannica) towards the top of the section.

16

Calcareous nannofossil biostratigraphy and sedimentary environment of Valanginian–Hauterivian rhythmites (Silesian Nappe, Polish Carpathians)

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Kędzierski M. , Ochabska A.

Annales Societatis Geologorum Poloniae

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2012

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tom Vol. 82, No. 3

225–-237

EN

The results of semi-quantitative and qualitative studies of nannofossil assemblages in dark to light grey, rhythmically bedded, calcareous mudstones of the Upper Cieszyn Beds, Silesian Nappe of the Outer Carpathians are presented. The vertical variation in the carbonate content of these mudstones and changes in the composition of nannofossil assemblages, as well as the Shannon diversity index (SI), result from humid-arid climate changes, driving the trophic conditions of surface waters and nannoplankton biocalcification. These changes were control- led by the variable influences of both the Tethyan and Boreal provinces. The light grey mudstones were deposited during the dominance of warm waters from the Tethyan realm and some nannoconids, typical of the warm, stratified water of lower palaeolatitudes, occur here. The dark grey mudstones represent influences of the Boreal province, indicated by the appearance of Crucibiscutum sp. and a generally higher biodiversity demonstrated by SI. Climatic changes affected the stratification of surface water, expressed also by different linear fits for pairs of SI, Watznaueria barnesiae and Rhagodiscus asper. On the basis of the presence of Eiffellithus striatus, E. windii and signals of both Tethyan and Boreal influences. the section studied represents the uppermost Valanginian– lowermost Hauterivian boundary interval, i.e., the upper part of the BC5/BC6 nannofossil zones, related to the furcillata-radiatus ammonite zones.

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First report on dinosaur tracks from the Burro Canyon Formation, San Juan County, Utah, USA : evidence of a diverse, hitherto unknown Lower Cretaceous dinosaur fauna

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Milàn J. , Chiappe L. M. , Loope D. B. , Kirkland J. I. , Lockley M. G.

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tom Vol. 85, No. 3

515--525

EN

The newly discovered White Mesa tracksite in the Burro Canyon Formation represents a snapshot of a diverse, Lower Cretaceous dinosaur fauna from south-eastern Utah. The tracks were found at a construction site where the sandstone had been bulldozed and broken up. All tracks were found as deep, well-preserved natural casts on the underside of the sandstone slabs. Individual theropod tracks are 19–57 cm in length; one peculiar track shows evidence of a possible pathological swelling in the middle of digit III and an apparently didactyl track is tentatively assigned to a dromaeosaurid. Individual sauropod tracks are found with pes lengths of 36–72 cm, and interestingly, three distinct shapes of manus tracks, ranging from wide banana shaped to rounded and hoof-like. Ornithopods are represented with individual tracks 18–37 cm in length; a sin gle track can possibly be attributed to the thyreophoran ichnogenus Deltapodus. Zircon U-Pb dating places the track-bearing layer in the Barremian, contemporary to the lower Yellow Cat Member of the Cedar Mountain Formation, which has a similar faunal composition based on both tracks and body fossils. This new track-fauna demonstrates the existence of a diverse dinosaurian assemblage in the lower part of the Burro Canyon Formation, which hitherto is not known to yield skeletalre mains.

18

Two ammonites from the Early Cretaceous deep-sea sediments of the Silesian Nappe, Polish Carpathians, and stratigraphic problems resulted from micropalaeontological dating of their sites

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Vašíček Z. , Gedl E. , Kędzierski M. , Uchman A.

Annales Societatis Geologorum Poloniae

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2010

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tom Vol. 80, No 1

25-37

EN

Two ammonites Teschenites subflucticulus Reboulet and Criosarasinella mandovi Thieuloy have been found for the first time in the Flysch Carpathians. They occur in the so far poorly dated Early Cretaceous flysch deposits of the Silesian Nappe at Poznachowice Dolne, in the Upper Cieszyn Shale and the Hradiště (Grodziszcze) beds lithotypes, respectively. Teschenites subflucticulus points to Late Valanginian (Furcillata Zone), but nanno- plankton points to Late Hauterivian-Late Barremian and dinocysts to Late Hauterivian, all analyzed from the same sample. Criosarasinella mandovi points also to Late Valanginian (Furcillata Zone), what is not in contra-diction with the nannoplankton assemblage (Early Valanginian-Early Barremian) analyzed from the same bed, but dinocysts suggest Late Hauterivian. Preservation of the ammonites and sedimentary features of their host beds exclude redeposition. The difference in age by almost 3 Ma years between the ammonites and microfossils cannot be satisfactorily explained according to the current knowledge on their biostratigraphic meaning; it is left as it is as a dilemma.

19

Wykształcenie i biostratygrafia wybranych profili górnej jury i dolnej kredy sukcesji braniskiej i pienińskiej pienińskiego pasa skałkowego Polski, na podstawie wapiennych dinocyst i kalpionellidów

75%

Hejnar J.

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

|

2008

|

tom T. 34, z. 3/1

174-175

20

The spicules of sponges from Lower Cretaceous of the Polish lowlands

75%

Sztejn J.

Bulletin of the Polish Academy of Sciences. Earth Sciences

|

1995

|

tom 43

|

nr 3