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Mikrofacje i diageneza wapieni oolitowych najniższego triasu w profilu Gorzów Wielkopolski IG 1 (zachodnia Polska)

Jasionowski Marek, Becker Anna

Przegląd Geologiczny

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2023

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Vol. 71, nr 5

292--297

EN

Lowermost Triassic oolitic limestones occur in the Gorzów Wielkopolski IG 1 borehole as thin intercalations (mostly less than 1 m thick) within laminated or massive reddish brown mudstones or sandy mudstones of the Baltic and Pomerania formations of the Lowerand Middle Buntsandstein, respectively. In order to characterize the microfacies and diagenesis of the limestones, 46 thin sections from 44 core specimens were investigated. The limestone intercalations are poorly diversified in terms of microfacies, especially in the lower part of the section (Baltic Formation), where almost exclusively fine-grained, well-sorted ooid grainstones occur. The upper part of the section (Pomerania Formation) is more diverse. In addition to grainstones similar to those of the Baltic Formation, coarse-grained and/or poorly sorted ooid grainstones, subordinate stromatolites, oncoid grainstones, and mudstones are present. The limestones are almost completely devoid of bioclasts. The only organic remains present in the thin sections are single rounded plates composed of apatite (possibly fish scales) and, even rarer, snail shells and small shells of other organisms (bivalves?, ostracods?), now dissolved (probably originally aragonitic) and visible only due to the preserved coatings of micritic calcite cement previously precipitated on them. The diagenesis of these deposits has not been very intensive and involves mainly cementation by calcite and subordinately by anhydrite, recrystallization of some ooids and other grains (including carbonate bioclasts), and to alesser extent by dissolution under pressure.

2

Palaeobiogeography, palaeoecology, and sequence stratigraphy of the Upper Jurassic carbonate succession of the Lar Formation, central Alborz Zone, Iran

Saleh Zahra, Reháková Daniela

Geological Quarterly

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2023

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Vol. 67, No. 2

art. no. 15

EN

Foraminifera, ammonites, and calcareous dinoflagellates were used for stratigraphy and, together with microfacies, for the assessment of the palaeoenvironmental conditions of the Upper Jurassic deposits in the central Alborz Zone of northern Iran. The Lar Formation (Lar Fm.) in the Polur section is of latest Oxfordian to early Kimmeridgian age. The ammonite Subnebrodites planula and the calcareous dinoflagellate Colomisphaera nagyi have been introduced as new biomarkers of the lower Kimmeridgian in the central Neo-Tethys. The distribution of calcareous dinoflagellates reflects possible dispersal routes along a narrow seaway between the western Neo-Tethys and the Alborz Zone in the central Neo-Tethys. The Terebella-Crescentiella associations of the Lar Fm. represent a low-energy setting under dysoxic conditions in the Central Neo-Tethys Ocean. The benthic foraminiferal assemblages in this formation show a high dominance of infaunal taxa and r-selected strategists. This assemblage is reminiscent of eutrophic conditions and low oxygen levels in the lower part of the Lar Fm. Good preservation of the hexactinellid sponges in the upper part of the Lar Fm. also indicates an oxygen-minimum zone. Three third-order depositional sequences can be distinguished in the study area based on six microfacies. Depositional sequence 1 (DS1) is composed mainly of argillaceous limestone and medium- to thick-bedded limestone, corresponding to an outer ramp-to-middle ramp environment. Depositional sequence 2 (DS2) comprises breccia limestone and thick-bedded limestone facies in its lower part and thin-bedded limestone to massive limestone in its upper part. The breccia limestone facies may be associated with subaerial exposure and reworking of previously deposited sediment during a relative sea level fall. The thin-bedded limestone to massive limestone of DS2 consists mainly of bioclastic mudstone to wackestone (outer ramp). These represent an deep-water outer homoclinal ramp facies. Depositional sequence 3 (DS3) consists mainly of massive limestone to thick-bedded limestone with a bioclastic peloidal microbial Crescentiella packstone (middle ramp). The relative stratigraphic positions of DSs1–3 and sequence boundaries in the uppermost Oxfordian to lower Kimmeridgian of the Polur area show a fair match to the upper Oxfordian to lower Kimmeridgian sequences (JOx7, JOx8, JKi1 and JKi2) on the global sea level curve.

3

Turonian-Coniacian (Upper Cretaceous) of the Babadag Basin (North Dobrogea, Romania) : integrated biostratigraphy and microfacies succession

Lodowski Damian Gerard, Walaszczyk Ireneusz Piotr, Grădinaru Eugen

Geological Quarterly

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2019

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Vol. 63, No. 1

39--64

EN

The Upper Turonian to Middle Coniacian (Upper Cretaceous) succession of the Babadag Basin (North Dobrogea, Romania) constitutes an apparently continuous fossiliferous carbonate succession. The presence of moderately rich inoceramid, ammonite and foraminiferal assemblages allows for the application of a precise biostratigraphic subdivision. The palaeoenvironmental conditions and evolution of the Babadag Basin during the Late Turonian-Middle Coniacian are inferred using microfacies analysis and foraminiferal spectra. Together, these suggest the Turonian-Coniacian Badabag Basin reflects relatively shallow-water conditions in a near-shore environment, punctuated by two regression events in the Late Turonian and in the Middle Coniacian.

4

Depositional environments, facies and diagenesis of the Upper Jurassic–Lower Cretaceous carbonate deposits of the Buila-Vânturariþa Massif, Southern Carpathians (Romania)

Pleş G., Bucur I. I., Săsăran E.

Annales Societatis Geologorum Poloniae

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2016

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Vol. 86, No. 2

165--183

EN

The Buila-Vânturariţa Massif consists of massive Upper Jurassic reef limestones (Kimmeridgian–Tithonian) and Lower Cretaceous (Berriasian–Valanginian, and Barremian–?Lower Aptian) deposits. Besides corals and stromatoporoids, a wide range of micro-encrusters and microbialites has contributed to their development. In this study, the authors describe briefly and interpret the main facies associations and present the microfossil assemblages that are important for age determination. The distribution of facies associations, corroborated with the micropalaeontological content and early diagenetic features, indicate different depositional environments. The carbonate successions show the evolution of the Late Jurassic–Early Cretaceous depositional environments from slope and reef-front to internal-platform sedimentary settings, including peritidal environments in the lowermost Cretaceous. Early diagenesis, represented by synsedimentary cementation in the form of micritization (including cement crusts in the reef microframework), followed by dissolution, cementation and dolomitization in a meteoric regime, and void-filling late cementation during the burial stage.

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Analiza statystyczna parametrów mikrofacji dolomitu głównego w granicznej strefie platformy węglanowej

Semyrka R., Jarzyna J. A., Krakowska P. I., Semyrka G.

Gospodarka Surowcami Mineralnymi

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2015

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T. 31, z. 1

123--140

PL

Duża liczba wyników badań laboratoryjnych parametrów zbiornikowych dolomitu głównego na obszarze platformy węglanowej, w rejonie wschodniej części platformy Gorzowa, w zatoce Noteci wraz z mikroplatformą Krobielewka, na półwyspie Grotowa, oraz na fragmencie platformy wielkopolskiej, sięgającym rejonu Pniew umożliwiła wykonanie wiarygodnych analiz statystycznych. Standardowe badania na próbkach skał (gęstości objętościowej, porowatości efektywnej i przepuszczalności fizycznej) wzbogacone zostały o wyniki pomiarów porozymetrii rtęciowej. Wyniki badań laboratoryjnych, przede wszystkim porozymetrii rtęciowej, rozszerzyły znacznie informację o skale zbiornikowej (dolomicie głównym) i przyczyniły się do wydzielenia różnorodnych mikrofacji oraz stref paleogeograficznych. Na podstawie wyników przeprowadzonej analizy statystycznej porównano parametry petrofizyczne trzech mikrofacji i stwierdzono, że utwory ziarnozwięzłe charakteryzowały się najlepszymi właściwościami zbiornikowymi. Dla tych utworów stwierdzono wysoką średnią porowatość efektywną oraz wysoką średnią porowatość dynamiczną dla gazu i ropy. Utwory te charakteryzowały się także wysoką przepuszczalnością. [...]

EN

Reliable statistical analysis was carried out for the Main Dolomite reservoir parameters on the area of carbonate platform in the vicinity of the east part of Gorzów Platform, in the Noteć Bay, together with Krobielewko Microplatform, on the Grotów Peninsula and on the part of Wielkopolska Platform, reaching Pniewy region thanks to large number of laboratory measurements results. The standard measurements on the core samples (bulk density, effective porosity and absolute permeability) were enriched by mercury porosimetry results. Laboratory measurements results, especially mercury porosimetry, extended considerably information about the reservoir rock (the Main Dolomite) and contributed to the separation of diverse microfacies and paleogeographic zones. Petrophysical parameters of the three microfacies were compared based on the results of statistical analysis. It was found that grainstones were characterized by the best reservoir parameters. For these microfacies high average effective porosity and average dynamic porosity for oil and gas were discovered. Additionally, grainstones characterized by high permeability. [...]

6

The isolated Wuchiapingian (Zechstein) Wielichowo Reef and its sedimentary and diagenetic evolution, SW Poland

Fheed A., Świerczewska A. T., Krzyżak A.T.

Geological Quarterly

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2015

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Vol. 59, No. 4

762--780

EN

The development of a relatively small and isolated part of the Wuchiapingian, Zechstein Wielichowo Reef was possible owing to a progressive subsidence and frequent sea level fluctuations. Three biofacies were distinguished within the studied object: (1) a shallow-water and highly energetic Acanthocladia biofacies, dominated by bryozoans and crinoids, with poorly preserved porosity, reduced mainly by calcite cementation and compaction; (2) the Horridonia biofacies comprising numerous brachiopods, preferring a moderate depth of water, with comparably poor porosity; and (3) the Fenestella/Kingopora biofacies rich in fossils of the highest variability, related to the deepest and calmest waters, occurring on the top of the profile and showing a significant effective porosity, reaching almost 13%. Among many diagenetic processes altering the reef, several lines of evidence suggest that it was the meteoric diagenesis to enhance its porosity the most extensively. Since no stromatolites are present, the final sea level decrease is interpreted to be rapid, hence creating conditions favourable for the meteoric dissolution. Some intraparticle porosity, however, seems to be of a depositional origin.

7

Aptian age of the “spotted limestone” (Pieniny Lime stone Formation) in Grajcarek Stream (Pieniny Klippen Belt, Poland)

Pszczółkowski A.

Annales Societatis Geologorum Poloniae

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2015

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Vol. 85, No. 1

21--42

EN

Planktonic foraminifera, calcareous dinocysts and nannofossils have been identified in thin sections of the “spotted limestone”, exposed in the Grajcarek Stream at Szlachtowa and assigned to the Pieniny Limestone Formation in the Magura Succession, Pieniny Klippen Belt (southern Poland). The new data indicate that the “spotted limestone” is older than was suggested in previous reports (Albian or Cenomanian?). The foraminiferal taxa belong mainly to the upper part of the Lower Aptian. The calcareous nannofossils may correspond to the Aptian NC6(?)-NC7 zones, whereas the assemblage of calcareous dinoflagellate cysts is less conclusive (Late Barremian-Aptian).

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The Permian and Triassic in the Albanian Alps

Gaetani M., Meço S., Rettori R., Henderson C. M., Tulone A.

Acta Geologica Polonica

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2015

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Vol. 65, no. 3

271--295

EN

The sedimentary succession of the Permian to Middle Triassic of the Albanian Alps is described, as part of the eastern Adria passive margin towards the Tethys. A carbonate ramp deepening towards NE in present day coordinates developed during the Middle Permian and was affected by block faulting with the deposition of carbonate breccia. The Early Triassic was characterized by intense terrigenous deposition with several cobble conglomerate units up to 80 m-thick, and by oolitic carbonate shoals. The fine clastic deposition ended gradually during the earliest Anisian and a wide calcarenitic ramp occupied the area, with small local carbonate mounds. Basinward, the red nodular limestone of the Han Bulog Formation was interbedded with calcarenitic material exported from the ramp. Drowning to more open conditions occurred towards the end of the Pelsonian. Subsequently, cherty limestone and tuffitic layers spread over the entire area. Towards the end of the Ladinian, with the end of the volcanic activity, red pelagic limestone was deposited locally for a short period. By the latest Ladinian most of the area returned to shallow-water conditions, with a peritidal carbonate platform. In the Theth area, in contrast, a basin with black organic-rich dolostone and limestone developed which seems to be unique in that part of the Adria passive margin. The occurrence of cobble conglomerate units in the Lower Triassic testifies to very active block faulting and high accommodation, not yet described for the area.

9

Dewońska seria węglanowa w otworze wiertniczym Trojanowice 2

Tomaś A.

Biuletyn Państwowego Instytutu Geologicznego

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2014

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nr 459

167--168

PL

Dewońską serię węglanową badano w otworze wiertniczym Trojanowice 2, usytuowanym na północny zachód od Krakowa. Jest ona reprezentowana przez dolomity, z nielicznymi poziomami brekcji śródwarstwowych i warstwę wapienia mikrytowego. Dolomity zawierają ślady pierwotnych struktur, ziarn (bioklasty, peloidy, intraklasty, ooidy) oraz relikty substancji mikrytowej. Powstały one w wyniku wczesnej dolomityzacji wapieni mikrytowych, które osadzały się w płytkim, spokojnym, prawdopodobnie izolowanym środowisku morskim. Serię dolomitową z otworu Trojanowice 2 zaliczono do eiflu–żywetu dolnego na podstawie podobieństwa do dolomitów występujących w innych otworach w masywach górnośląskim i małopolskim.

EN

The Devonian carbonate succession was examined in the Trojanowice 2 borehole located northwest of Kraków. It is represented by dolomites with infrequent intrastratal breccias and a micrite limestone layer. The dolomites contain traces of primary structures, grains (bioclasts, peloids, intraclasts and ooids) and relics of micritic matter. They formed as a result of early dolomitization of micrite limestones deposited in a shallow, quiescent and probably isolated marine environment. The dolomite succession from the Trojanowice 2 borehole has been assigned to the Eifelian–Lower Givetian based on the similarity to the dolomites known from other boreholes in the Upper Silesian and Małopolska blocks.

10

Lower Jurassic to lower Middle Jurassic succession at Kopy Sołtysie and Płaczliwa Skała in the eastern Tatra Mts (Western Carpathians) of Poland and Slovakia: stratigraphy, facies and ammonites

Iwańczuk J., Iwanow A., Wierzbowski A.

Volumina Jurassica

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2013

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Vol. 11, no. 1

19–-58

EN

The Lower Jurassic and the lower part of the Middle Jurassic deposits corresponding to the Sołtysia Marlstone Formation of the Lower Subtatric (Krížna) nappe in the Kopy Sołtysie mountain range of the High Tatra Mts and the Płaczliwa Skała (= Ždziarska Vidla) mountain of the Belianske Tatra Mts in the eastern part of the Tatra Mts in Poland and Slovakia are described. The work concentrates both on their lithological and facies development as well as their ammonite faunal content and their chronostratigraphy. These are basinal deposits which show the dominant facies of the fleckenkalk-fleckenmergel type and reveal the succession of several palaeontological microfacies types from the spiculite microfacies (Sinemurian–Lower Pliensbachian, but locally also in the Bajocian), up to the radiolarian microfacies (Upper Pliensbachian and Toarcian, Bajocian–Bathonian), and locally the Bositra (filament) microfacies (Bajocian–Bathonian). In addition, there appear intercalations of detrital deposits – both bioclastic limestones and breccias – formed by downslope transport from elevated areas (junction of the Sinemurian and Pliensbachian, Upper Toarcian, and Bajocian). The uppermost Toarcian – lowermost Bajocian interval is represented by marly-shaly deposits with a marked admixture of siliciclastic material. The deposits are correlated with the coeval deposits of the Lower Subtatric nappe of the western part of the Tatra Mts (the Bobrowiec unit), as well as with the autochthonous-parachthonous Hightatric units, but also with those of the Czorsztyn and Niedzica successions of the Pieniny Klippen Belt, in Poland. The character of the deposits in the sequences, and their biostratigraphical analysis, show that sedimentation during the Early Jurassic, and up to the Late Bajocian, was controlled by rifting phases which were active at the junction of the Sinemurian and Pliensbachian (Zliechov Phase), during the Late Pliensbachian and Toarcian (Devín Phase), and during the Bajocian (Krasín Phase). The onset of pelagic sedimentation overlying the rift strata took place during the latest Bajocian. Selected ammonite taxa are illustrated and discussed.

11

Facies and sedimentation of Coniacian deposits of the Kraków Swell in the Wielkanoc area (southern Poland)

Olszewska-Nejbert D., Świerczewska-Gładysz E.

Geological Quarterly

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2013

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Vol. 57, No. 1

1–-16

EN

Coniacian deposits, ca. 1.5 m thick, cropping out in the Wielkanoc Quarry, north of Kraków in southern Poland, consist of firm, nodular and, less commonly, marly limestones with horizons of in situ, slightly phosphatized hexactinellid sponges and thick-shelled inoceramid bivalves. The succession is composed of foraminiferal-inoceramid packstones with common sand-sized quartz and glauconite grains at the base, passing upwards into foraminiferal or foraminiferal-inoceramid wackestones with or without rare glauconite. A microfacies analysis shows that planktonic foraminifers are the dominant forms, while benthic forms are rare. The facies indicates that sedimentation in the Wielkanoc area on the Kraków Swell, which separated the deeper Mid-Polish Trough Zone to the north-east and the Opole Trough Zone to the south-west, was generally calm (documented by abundant wackestones) and slow (indicated by the dominant sedimentary “coccolith system” and presence of glauconite) during the Coniacian. Rare episodes of non-deposition are recorded by episodes of phosphatization and minor intra-Coniacian discontinuity surfaces. The presence of hexactinellid sponges in the section studied are consistent with a calm environment, below the storm-wave base, with low rates of sedimentation. Subhercynian (latest Turonian–Coniacian Ilsede Phase) local tectonic movements had an important influence on the evolution of the region. They presumably led to subsidence of the Wielkanoc Block during the Early Coniacian. These movements were probably associated with activity on the Kraków–Myszków Fault Zone.

12

Experimental method for estimation of compaction in the Oxfordian bedded limestones of the southern Kraków-Częstochowa Upland, Southern Poland

Kochman A., Matyszkiewicz J.

Acta Geologica Polonica

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2013

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Vol. 63, no. 4

681--696

EN

The Upper Jurassic carbonates exposed in the southern part of the Kraków-Częstochowa Upland are well known for their significant facies diversity related to the presence of microbial and microbial-sponge carbonate buildups and bedded detrital limestone in between. Both the buildups and detrital limestones revealed differential susceptibility to compaction which, apart from differential subsidence of the Palaeozoic basement and synsedimentary faulting, was one of the factors controlling seafloor palaeorelief in the Late Jurassic sedimentary basin. The compaction of the detrital limestones has been estimated with an experimental oedometric method in which specially prepared mixtures made of ground limestones from a quarry in the village of Żary were subjected to oedometer tests. The diameters of the detrital grains and their percentages in the limestones were determined by microscopic examinations of thin sections. The diameters were assigned to predetermined classes corresponding to the Udden-Wentworth scale. The rock samples were then ground down to the grain sizes observed in thin sections. From such materials, mixtures were prepared of grain size distributions corresponding to those observed in thin sections. After adding water the mixtures were subjected to oedometer tests. Analysis of the compression of such mixtures under specific loads enabled preparation of a mathematical formula suitable for the estimation of mechanical compaction of the limestone. The obtained values varied from 27.52 to 55.53% for a load corresponding to 300 metres burial depth. The most significant effect of mechanical compaction was observed for loads representing only 2 metres burial depth. Further loading resulted in a much smaller reduction in sample height. The results of the oedometer tests cannot be used directly to determine compaction of the detrital limestones. Mainly because microscopic observations of thin sections of the experimental material show that chemical compaction was also an important factor influencing thickness reduction of the limestones.

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Fatrzańska przynależność utworów retyku w profilu "Nad Moreną" (rejon Przysłopu Miętusiego) : korekta stratygrafii hronikum w Tatrach

Gaździcki A., Uchman A.

Przegląd Geologiczny

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2012

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Vol. 60, nr 6

333-340

EN

The "Nad Moreną" section (Triassic–Jurassic boundary interval) in the Tatra Mts. was previously ascribed to the Choč Nappe (Hronicum domain) or to the Križna Nappe (Fatricum domain). Microfacies analysis of the Rhaetian limestones proves that they belong to the Fatra Formation, particularly because of the fossil biota assemblages. This study definitely proves the Križna (Fatricum) provenance of the "Nad Moreną" section and corrects stratigraphy of the Choč Nappe (Hronicum domain) in the Tatra Mts.

14

Biostratigraphy and palaeoenvironment of the Kimmeridgian-Lower Tithonian pelagic deposits of the Krížna Nappe, Lejowa Valley, Tatra Mts. (southern Poland)

Jach R., Řeháková D., Uchman A.

Geological Quarterly

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2012

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Vol. 56, No. 4

773--788

EN

The Upper Jurassic strata of the Krížna Unit in the Tatra Mts. comprises pelagic, fine-grained and well-oxygenated deposits. They are represented by red radiolarites and radiolarian limestones (Czajakowa Radiolarites Formation), red nodular limestones (Czorsztyn Limestones Formation) and wavy, platy or nodular light grey and reddish limestones and marlstones (Jasenina Formation). These deposits are mainly wackestones characterized by a succession of the following microfacies: radiolarian, filament-Saccocoma, Saccocoma and Globochaete–Saccocoma. The section comprises four calcareous dinoflagellate zones, i.e. the Late Kimmeridgian Moluccana Zone, and the Early Tithonian Borzai, Pulla and Malmica zones. In the uppermost part of the studied section, the Early Tithonian Dobeni Subzone of the Chitinoidella Zone has been identified. Using these biostratigraphic data, the sedimentation rate for the Late Kimmeridgian (Borzai Zone) and Early Tithonian (Dobeni Subzone of the Chitinoidella Zone) interval is estimated as 3.7 m/my. This is in accordance with the general trend of increasing sedimentation rate through the Tithonian and Berriasian. The increased supply of clastic material in the Jasenina Formation may have been caused by climate changes and continental weathering. The sedimentation was controlled mainly by eustatic changes and fluctuations in ACD and CCD levels.

15

Stratigraphy and microfacies of the Jurassic and lowermost Cretaceous of the Veliky Kamenets section (Pieniny Klippen Belt, Carpathians, Western Ukraine)

Rehakova D., Matyja B., Wierzbowski A., Schlogl J., Krobicki M., Barski M.

Volumina Jurassica

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2011

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Vol. 9, no. 1

61-104

EN

The Veliky Kamenets section in the eastern part of the Pieniny Klippen Belt in the Ukrainian Carpathians shows a well exposed, 83 m thick succession composed of Jurassic and lowermost Cretaceous (Berriasian) deposits. The terrigenous part of the section includes: gravels with a sandy matrix (unit 1A), massive grey-green sandstones (unit 1B) and shales with intercalations of siltstones/sandstones and oyster/gastropod lumachelles (unit 2). Organic-walled dinoflagellates document the Toarcian-Aalenian age of the siliciclastic deposits of unit 2. The carbonate part of the succession embraces: stromatactis mud-mounds interfingering with crinoidal limestones (unit 3A), lower nodular limestones (unit 3B), cherty limestones (unit 3C), upper nodular limestones (unit 3D), pink pelitic limestones (unit 3E), limestones with a volcanogenic bed (unit 5) and limestone breccia limestones (unit 6). This succession has yielded abundant ammonites from the Bathonian, Oxfordian and Kimmeridgian (with a stratigraphical hiatus covering the Callovian and Lower Oxfordian), as well as calcareous dinoflagellates (from the Upper Oxfordian towards the top of the succession), and calpionellids (in the Tithonian and Berriasian). Detailed stratigraphical study of the succession based both on ammonites and microfossils has resulted in the recognition of biostratigraphical units and their correlation with the chronostratigraphical scale.The microfacies recognized in the pelagic part of the succession include: the “filament” (Bositra) microfacies (Bathonian), the planktonic foraminifer microfacies (Oxfordian), the Saccocoma microfacies (Kimmeridgian to Upper Tithonian), and the calpionellid microfacies (Upper Tithonian–Berriasian). The volcanogenic rocks (lava flows and volcanic ash) appear in the topmost part of the succession (units 4 to 6) and this volcanic event is very precisely located in the Elliptica-Simplex chrons of the Middle and Late Berriasian.

16

Mikrofacje utworów węglanowo-silikoklastycznych miocenu w dolinie Opatówki (północna marginalna strefa zapadliska przedkarpackiego)

Czarniecka U.

Przegląd Geologiczny

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2011

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Vol. 59, nr 9

625-632

EN

The study concerns the Miocene carbonate and mixed siliciclastic-carbonate deposits of the Pińczów and Chmielnik Formations. They are located on the south-eastern slopes of the Holy Cross Mountains. Based on the thin sections analysis the framework components, kinds of cements and character of porosity were described. The framework components were qualified according to their size, roundness and sorting. Two types of components predominate: carbonate intraclasts and non-carbonate extraclasts. Among the intraclasts, mainly well rounded algal bioclasts occur. Moreover, poorly rounded skeletal elements of bryozoans, foraminifera, echinoids, serpulids, bivalves, gastropods, as well as rare glauconite grains have also been observed. The extraclasts are represented mainly by quartz grains and rare litoclasts, among which fragments of sandstones and limestones were recognized. These grains are poorly rounded or angular. Overall, the framework components are poorly sorted. Microspar is the main kind of pore-filling carbonate cements. The examined deposits have considerable porosity. The following types of porosity were distinguished: intergranular, intragranular, intercrystalline, moldic and vuggy. Based on the results of thin sections analysis, seven types of microfacies were distinguished: algal foraminiferal packstone, algal packstone, quartz-rich algal packstone, lithoclastic algal packstone, quartz-rich bryozoan algal packstone, bryozoan packstone, quartz-rich bryozoan packstone.

17

Wapiennik Breccia Member (Pieniny Klippen Belt, Poland) - revised stratigraphy and origin

Arabas A., Sidorczuk M., Olszewska B.

Geological Quarterly

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2011

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Vol. 55, No. 1

49-62

EN

The Wapiennik Breccia Member was originally attributed to the Czorsztyn Limestone Formation of the Czorsztyn Succession in the Pieniny Klippen Basin. The breccia was assigned previously to the Callovian-Oxfordian. Based on micropalaeontological and microfacies studies we have determined its age as late Albian. At this time the Czorsztyn Swell was affected by extensional faulting, with subsequent submarine erosion of scarps. The re-evaluated age of the breccia, as well as the lithology of its clasts and its matrix that contains Cretaceous foraminifera, indicate the assignment of the Wapiennik Breccia Member to the Chmielowa Formation.

18

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

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

Annales Societatis Geologorum Poloniae

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2011

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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.

19

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

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

Annales Societatis Geologorum Poloniae

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2011

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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.

20

Zapis litologiczny i mikrofacjalny osadów euksynicznych kambru górnego i tremadoku obniżenia bałtyckiego (północna Polska)

Szymański B.

Biuletyn Państwowego Instytutu Geologicznego

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2008

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nr 430

113-113

PL

W sekwencji litologicznej kambru górnego i tremadoku polskiego fragmentu obniżenia bałtyckiego wyróżniono - opierając się na makro- i mikroskopowej zmienności cech sedymentacyjnych i petrograficznych osadów - dwie jakościowo odmienne grupy mikrofacji hydrogenicznych - grupę mikrofacji terygenicznych (silikoklastycznych) i grupę mikrofacji węglanowych. Grupę wyróżnionych mikrofacji terrygenicznych tworzą: zlepieńce piaszczyste i piaszczysto-glaukonitowe (COsa-COsa-gl), piaskowce kwarcowe (arenity) (SAqw) oraz czarne iłowce i mułowce bitumiczne (CLbi-SLbi). Grupę mikrofacji węglanowych tworzą: greistony (GRbc), greistony/pakstony bio-klastyczne (GRbc/PAbc), pakstony/wakstony bioklastyczne (PKbc/WKbc) oraz sparyty i mikrosparyty (LMre). Zasięg stratygraficzny mikrofacji grupy węglanowej jest zróżnicowany przestrzennie i przyporządkowany kolejno: w profilach części zachodniej obniżenia bałtyckiego - interwałowi poziomów Agnostus pisiformis-Acerocare kambru górnego (formacja z Piaśnicy), a w profilach części środkowej - przedziałowi poziomów Olenus i Agnostus (Homagnostus) obesus-Parabolina spinulosa włącznie (formacja z Młynar). Sumaryczna miąższość sekwencji osadów silikoklastyczno-węglanowych kambru górnego i tremadoku waha się od 34,5 m w zachodniej i północno-zachodniej części obniżenia bałtyckiego (otwór wiertniczy A21-1/95) do 0,05 m w skrajnie wschodniej jego części (otwór wiertniczy Jezioro Okrągłe IG 2).

EN

The paper presents microfacies characteristics of Upper Cambrian and Tremadocian siliciclastic and carbonate rocks from the Polish part of the Baltic Depression (Northern Poland). Whitin the Upper Cambrian and Tremadocian sequence two different groups of hydrogenic microfacies can be distinguished: terrigenous (siliciclastic) and carbonate microfacies. The terrigenous (siliciclastic) group consists of three microfacies types: sandy conglomerates and sandy-glauconitic conglomerates (COsa-COsa-gl); quartz sandstones (arenites) (SAqw), black bituminous claystones (shales) and black bituminous siltstones (SLbi-CLbi). The carbonate group consists of four microfacies types: bioclastic grainstones (GRbc), bioclastic grainstones/packestones (GRbc/PAbc); bioclastic packstones/wackestones (PKbc/WKbc) and sparites and microsparites (LMre). Stratigraphic range of the carbonate mocrofacies is spatially variable and assigned respectively to the Upper Cambrian Agnostus pisiformis-Acerocare zones in the sections from the western part of the Baltic Depression, and to the Olenus and Agnostus {Homagnostus) obesus-Parabolina spinulosa zones (Młynary Formation) in the sections from the central part. The total thickness of the Upper Cambrian-Tremadocian siliciclastic-carbonate sequence varies from 34.5 m in the western and north-western part of the Baltic Depression (21-1/95 borehole) to 0.05 m in its easternmost area (Jezioro Okrągłe IG 2 borehole).