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1

Badania mineralizacji REE w utworach pokrywy osadowej masywu Tajna

Dymowski Witold

Przegląd Geologiczny

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2021

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Vol. 69, nr 7

426--433

EN

The paper presents a study of occurrences of REE mineralization in Lower Triassic and Middle Jurassic sedimentary rocks in the Tajno Massif, NE European Platform. Manifestations the REE mineralization occurin siltstones, sandstones, conglomerates and debris, and in other mixed weathered rocks.

2

Provenance of heavy minerals to the Middle and Upper Jurassic epicontinental deposits of NW Poland

Bembenek Kinga, Woronko Barbara, Ziółkowski Piotr

Geological Quarterly

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2021

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Vol. 65, No. 1

art. no. 2

EN

The source of clastic material supplied to the epicontinental sea during the Middle and Late Jurassic in the Pomeranian Segment of the northern part of the Mid-Polish Trough is analysed, using deposits from the Rzeczyn PIG-1 borehole that represent the Łyna, Chociwel, Brda, Pałuki, Kcynia and Rogoźno formations. Heavy mineral analysis, including weathering indices (ZTR, GZI, RZI and Q) and standardised scores for each mineral species, shows that each formation is characterized by a different heavy minerals association. In each association, transparent minerals include both ultrastable minerals (zircon, tourmaline and rutile), occurring in various proportions, and unstable minerals. This indicates that deposits subject to earlier multiple reworking were eroded from the surrounding landmasses. Most probably these deposits represented Triassic rocks, although fresh weathering covers were also eroded. The main direction of clastic material supply was from the N and NW, and to a lesser degree from the NE. The main reasons for changes in the source areas were probably sea level oscillations, while during regressions, exposed parts of the seabed became source areas of clastic material. Conversely, during transgressions, parts of the seabed became cut off from the supply of clastic material from eroded landmasses.

3

The siliciclastics/carbonates shift in the Jurassic of the Western Caucasus (central northern Neo-Tethys): reconsidering research over the last 50 years

Ruban Dmitry A.

Geologos

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2019

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Vol. 25, No. 2

153--162

EN

A chain of carbonate platforms evolved in the northern Neo-Tethys during the Late Jurassic, but current knowledge remains incomplete as long as data from several larger regions, such as the Western Caucasus, are not included. In order to fill this gap, it is here suggested to reconsider the information accumulated chiefly during Soviet times. Although these data are too general, they still matter with regard to some regional characteristics and tentative interpretations. Available data on the spatio-temporal distribution of Bajocian-Callovian sedimentary rocks are summarised in a novel way which permits documentation of depositional trends at six representative localities in the Western Caucasus. The extent of the carbonate platform increased at two localities since the Late Callovian and at a third since the Middle Oxfordian. Three additional sites were characterised either by non-deposition or deep-marine sedimentation. The onset of carbonate platform development marked a remarkable shift from chiefly siliciclastic to carbonate deposition, although this event was not sudden everywhere. The Bathonian pulse of tectonic activity, coupled with the eustatic sea level rise, allowed shelves to expand during the Callovian-Oxfordian, with a reduction in siliciclastic input from islands and seawater that became well oxygenated and warmer. These conditions were conducive to biogenic carbonate production, allowing the carbonate platform to expand subsequently.

4

Long-term shoreline shifts on continental blocks during the Bajocian: an updated interpretation based on synthetic stratigraphical and palaeogeographical developments on regional scales

Ruban Dmitry A., Sallam Emad S.

Geologos

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2019

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Vol. 25, No. 1

43--50

EN

Available reconstructions of Jurassic global sea level changes differ and are in need of an update. New stratigraphical charts and palaeogeographical developments for a number of large continental blocks or their portions of these (e.g., Germany, India, northeast Africa, northwest Australia, the Russian Platform and western Siberia) reveal regional long-term shoreline shifts (i.e., transgressions and regressions) during the Bajocian Stage (168.3–170.3 Ma). A comparison of these allows to document only a single coherent feature, namely the earliest Bajocian transgression, in the majority of the continental blocks considered. Undoubtedly, this event was triggered by a eustatic rise. However, long-term shoreline shifts were either weak to absent or differed between the blocks during almost the entire Bajocian, thus providing evidence of the apparent stability of global sea level and the importance of regional tectonic activity as a control mechanism on particular transgressions and regressions. Interestingly, it appears that the earliest Bajocian eustatic rise was a constituent of a long-term eustatic pattern; the nature of this event has yet to be fully understood. Generally, the findings presented here are in better agreement with Anthony Hallam’s view of Jurassic eustasy and question some other global sea level reconstructions.

5

Instrumental methods applied in the investigations of carbonate minerals in the Middle Jurassic sideritic rocks with respect to diagenetic processes

Kozłowska Aleksandra

Biuletyn Państwowego Instytutu Geologicznego

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2019

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nr 474

31--42

EN

Carbonate minerals in the Middle Jurassic sideritic rocks from the Polish Lowlands, north-eastern margin of the Holy Cross Mountains and the Częstochowa region have been studied applying accessible instrumental methods. The following techniques were applied: polarization microscope, staining with the Evamy’s solution, cathodoluminescence, microprobe, fluid inclusions and isotopic analyses. Most of these methods were not available either in the 20ies of the past century when studies of sideritic iron ores in Poland had begun, or in 50ies and 60ies when they were in full progress. The sideritic rocks are mainly represented by clayey siderites (they contain also muddy and sandy varieties), sideritic sandstones and sideritic coquina, less frequently by sideritic conglomerates and mudstones. Sideroplesite is the main carbonate mineral that builds the sideritic rocks, while pistomesite and siderite are less frequent. Fe-calcite and Fe-dolomite, ankerite, and sporadic dolomite occur in lesser amounts. Syderoplesite and siderite have crystallized in the early diagenesis (eodiagenesis), in the zone of microbiologic methanogenesis, at temperatures of about 20°C, from the porous waters of marine origin, or from marine waters mixed with fresh waters. Sideroplesite enriched in magnesium, pistomesite, calcite and ankerite sequently have formed at the later diagenetic stage (mezodiagenesis). These minerals have crystallized at temperatures above 60°C, from the porous waters of marine origin, or from the fluid which interacted with the adjacent rocks. Fe-calcite was formed in the zone of microbiologic methanogenesis, while the ankerite – in the zone of thermal decarboxylation.

XX

Na podstawie dostępnych obecnie metod instrumentalnych zbadano minerały węglanowe skał syderytowych jury środkowej z Niżu Polskiego, północno-wschodniego obrzeżenia Gór Świętokrzyskich i rejonu Częstochowy. Zastosowano: mikroskop polaryzacyjny, barwienie roztworem Evamy’ego, katodoluminescencję, mikrosondę energetyczną, analizę inkluzji fluidalnych i izotopową. Większość z tych metod nie była dostępna w latach dwudziestych, kiedy rozpoczęto badania syderytowych rud żelaza w Polsce, ani w latach pięćdziesiątych i sześćdziesiątych, kiedy były kontynuowane. Skały syderytowe są reprezentowane głównie przez: syderyty ilaste (obejmują również odmiany mułkowe i piaszczyste), piaskowce syderytowe i muszlowce syderytowe, rzadziej przez zlepieńce syderytowe i mułowce syderytowe. Głównym minerałem węglanowym budującym skały syderytowe jest syderoplesyt, rzadziej pojawiają się pistomesyt i syderyt. W zmiennych ilościach występują Fe-kalcyt oraz Fe-dolomit i ankeryt, sporadycznie dolomit. Syderoplesyt i syderyt krystalizowały we wczesnej diagenezie (eodiagenezie) w strefie mikrobiologicznej metanogenezy w temperaturze ok. 20°C z wód porowych pochodzenia morskiego lub wód morskich zmieszanych z wodami słodkimi. W późniejszym etapie diagene¬zy (mezodiagenezie) tworzyły się w kolejności: syderoplesyt z większą zawartością magnezu, pistomesyt, kalcyt i ankeryt. Minerały te krystalizowały w temperaturze powyżej 60°C z wody porowej pochodzenia morskiego lub wody, która weszła w reakcję z otaczającymi skałami. Fe-kalcyt tworzył się w strefie mikrobiologicznej metanogenezy, natomiast ankeryt w strefie termalnej dekarboksylacji.

6

Skały syderytowe jury środkowej Kujaw : studium petrologiczne

Maliszewska A., Kozłowska A., Kuberska M.

Przegląd Geologiczny

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2018

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Vol. 66, nr 4

240--251

EN

The paper presents the results of new mineralogical and petrographic analyses of Middle Jurassic sideritic rocks in the Kujawy area. The scope of the research has been extended to the Ciechocinek-Brześć Kujawski-Wojszyce zone, where clayey and sandy siderites and sideritic coquina form only inserts in siliciclastic rocks. Early diagenetic sideroplesite and mesodiagenetic sideroplesite, Fe-dolomite, ankerite, pistomestite and calcite occur among carbonate minerals. They are accompanied by an early diagenetic green mineral called chamosite and identified as berthierine in the XRD analysis. The richest mineral composition occurs in the sideritic coquina containing various shell elements, often also ooids. It is suggested that the formation of the coquina in the Klodawa-Łęczyca anticline area was caused by saline movements of the Cimmerian orogeny. The start-up and blending of salt masses and the rockfracture contributed to the intensive circulation of mineralizing solutions and the development of diagenetic processes, especially the replacement of unstable components and the cementation of Jurassic sediments throughout the Kujawy area.

7

Utwory jury środkowej przedgórza Karpat na obszarze Wadowice-Busko-Rzeszów, południowa Polska

Moryc W.

Prace Państwowego Instytutu Geologicznego

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2018

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T. 205

5--55

PL

Utwory jury środkowej na obszarze przedgórza Karpat polskich występują w dwóch rejonach, północno-wschodnim (Księżpol-Nowy Lubliniec-Lubaczów) opracowanym przez autora w 2004 r. i południowym (Wadowice-Busko-Rzeszów), będącym tematem monografii. Jura środkowa rejonu Wadowice-Busko-Rzeszów jest zbudowana głównie z utworów silikoklastycznych o miąższości przekraczającej 300 m, reprezentujących wiek co najmniej od bajosu do keloweju włącznie. W monografii przedstawiono wyniki badań uzyskane w 148 otworach wiertniczych, skorelowanych na podstawie wykresów geofizyki wiertniczej oraz oznaczeń fauny i flory. Szczegółowo omówiono stosunki dotyczące miąższości utworów poszczególnych poziomów środkowojurajskich oraz przedstawiono tektonikę i paleogeografię tych skał. Podkreślono przekraczające ułożenie utworów i transgresywny postęp morza tetydzkiego, stopniowo zwiększającego zasięg i zajmującego coraz większe obszary lądowe.

EN

Middle Jurassic sediments in the Polish Carpathian Foreland occur in two regions: northern (Księżpol-Nowy Lubliniec-Lubaczów) described by Author in 2004 and the southern (Wadowice-Busko-Rzeszów), considered here. The latter contains mainly siliciclastic sediments of thickness exceeding 300 m, whose age range from (at least) Bajocian to Callovian. The study presents results obtained from boreholes, correlated on the basis of logging diagrams and the fauna and flora. The thickness of particular Middle Jurassic series, their tectonics and palaeogeography are discussed in details. The transgressive arrangement of the sediments and the transgressive advance of the Tethyan Ocean, which gradually covered increasingly large areas of land, is evidenced.

8

Sedimentological study of the Nikolčice Formation : evidence of the Middle Jurassic transgression onto the Bohemian Massif (subsurface data)

Nehyba S., Opletal V.

Geological Quarterly

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2017

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Vol. 61, No. 1

138--155

EN

The Jurassic sedimentary succession along the eastern margin of the Bohemian Massif starts with mostly fluvial deposits of the Gresten Formation and continues after marine transgression with the deposition of the Nikolčice Formation (Middle Jurassic, Callovian). The provenance and depositional environment of the Nikolčice Formation showed that deposition occurred within offshore, transitional zone, shoreface, foreshore and littoral sand bar environments; however, shoreface and foreshore deposits dominate in the cores studied. The crystalline units along the eastern margins of the Bohemian Massif represent the primary source of deposits of the Nikolčice Formation. An important role was played by acidic and intermediate plutonites and highly metamorphosed metasedimentary rocks (granulite and amphibolite metamorphic facies), which indicates an advanced stage of erosion of the source area. The role of volcanic and intrusive rocks was small. The primary source was followed by an additional recycled source from older sedimentary rocks (especially the Moravo-Silesian Paleozoic deposits – the Líšeň Formation, the Myslejovice Formation). A similarity of the source areas for the Nikolčice Formation and the underlying Gresten Formation was recognized. Identified differences in their source areas are mainly explained by varied erosional levels due to successive exhumation of the source Variscan orogen and possibly also by an expansion of the source area.

9

Tubular tempestites from Jurassic mudstones of southern Poland

Leonowicz P. M.

Geological Quarterly

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2016

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Vol. 60, No. 2

385--394

EN

This paper presents tubular tempestites from southern Poland and their application for environmental and sequence stratigraphy interpretation. Tubular tempestites are present in muddy successions of the Lower Jurassic Ciechocinek Formation and in the Middle Jurassic Częstochowa Ore-Bearing Clay Formation in the Silesian-Kraków region. They occur as sand-filled tubes of Spongeliomorpha and Thalassinoides entrenched in the mudstone, which form two characteristic horizons. Tubes were emplaced in semi-consolidated substrate and filled with sand brought by storm-generated bottom currents. The trace fossils reveal features typical of Glossifungites ichnofacies associated firmgrounds, which record discontinuities in the stratigraphical record, linked with a depositional hiatus or condensation and erosion of the sea-floor. The coincidence of these horizons with early phases of regional transgressions suggests that they represent transgressive surfaces of erosion. Their limited spatial extent probably resulted from varying intensity of erosion, which locally scoured deeply down to already consolidated substrate, whereas in other places erosion was weaker or even absent, and thus it is not marked in the sedimentary record there.

10

Temperature and isotopic relations in carbonate minerals in the Middle Jurassic sideritic rocks of central and southern Poland

Jarmołowicz-Szulc K., Kozłowska A.

Geological Quarterly

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2016

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Vol. 60, No. 4

881-892

EN

The present study assesses the physico-chemical character of the fluids responsible for the genesis of carbonate minerals in the Middle Jurassic sideritic rocks at the northeastern margin of the Holy Cross Mts. and in the Częstochowa region. These rocks occur at present at depths between 30 and 600 m. Fluid inclusion and isotopic analyses have been performed in the carbonate minerals from sideritic sandstones, clayey siderites and sideritic coquinas. Siderite is the main carbonate mineral of the sideritic rocks. Calcite and ankerite are also present. The siderite is represented by two varieties, Mg-rich siderite (sideroplesite, less commonly – pistomesite) and siderite. Two generations of siderite have been distinguished – an early and a late one. The early siderite was formed at temperatures of about 20°C in the zone of microbiological methanogenesis from marine waters with some influence of meteoric waters (δ18O from –7.84 to –1.92‰ VSMOW). The late siderite crystallized at temperatures of about 62–110°C from pore waters enriched in 18O (δ18O >0‰ VSMOW) as compared with the isotopic composition of the waters responsible for the early siderite generation. The conducted fluid inclusion analyses point to formation of the cements from complex fluids of brine and carbon dioxide character, with densities slightly exceeding 1 g/cm3 and salinities varying from 10.5 to 16.9 wt.% NaCl eq. and from 6.4 to 14.0 wt.% NaCl eq. in the Holy Cross Mts. and in the Częstochowa region, respectively. The homogenization temperatures lie in the intervals of 62–110°C and 60–97°C, respectively and represent elevated values compared with data from the Polish Lowlands. Apart from burial, other heat sources must have been important for the lithogenesis of the Middle Jurassic deposits.

11

A Bajocian (Middle Jurassic) marine gastropod assemblage from the Badamu Formation, Central Iran

Ferraris M., Binazadeh T., Kaim A.

Annales Societatis Geologorum Poloniae

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2016

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Vol. 86, No. 3

329--340

EN

Nine species of gastropods are reported from the Bajocian (Middle Jurassic) part of the Badamu Formation of Central Iran. This is the first report of a gastropod assemblage of this age from the shelves of the Kimmerian Continent. Seven species belong to the Vetigastropoda and two to the Caenogastropoda. Two new species, the pleurotomariid Bathrotomaria iranica sp. nov. and the eucyclid Eucycloidea badamuensis sp. nov., are described. The remaining species are left in open nomenclature owing to poor preservation. The composition of the gastropod association is strongly reminiscent of other Tethyan gastropod faunas, in particular those from the southern shores of the Tethys (India and Arabia) and from southern Europe. This indicates a relatively uniform distribution of gastropod faunas along the Middle Jurassic shores of the western Tethys.

12

Berthierine in the Middle Jurassic sideritic rocks from southern Poland

Kozłowska A., Maliszewska A.

Geological Quarterly

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2015

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Vol. 59, No. 3

551--564

EN

A characteristic green and yellow-brown clay mineral from sideritic rocks was studied from 14 boreholes penetrating the Middle Jurassic strata of the northeastern margin of the Holy Cross Mountains and Częstochowa region, using polarizing and scanning electron microscopes, cathodoluminescence and X-ray analysis and revealing the presence of berthierine. In these sideritic rocks, berthierine occurs mainly in Lower and Middle Bathonian strata deposited in shoreface and deltaic environments of the northeastern margin of the Holy Cross Mountains, and in Upper Bajocian deposits of both areas studied. It forms the clay cement of sideritic rocks, fills voids in bioclasts and is also present in ooids. Ooids consisting of berthierine have been affected by mechanical compaction and mainly carbonate replacement. Berthierine ooids, replaced by sideroplesite, pistomesite, Fe-calcite or ankerite, and rarely by pyrite and altered by kaolinite, occur commonly. Berthierine ooids of the Bathonian sideritic rocks are typically better preserved, compared to those from the Bajocian and Aalenian. Berthierine crystallised in the eodiagenesis stage in suboxic conditions below the water-sediment interface, where iron-bearing freshwater mixed with sea water. It is chemically and structurally unstable and, during the mesodiagenetic stage at higher temperatures, could transform to chamosite by recrystallisation.

13

Rewitalizacja kamieniołomu skał jurajskich w Wieluniu w celu wykorzystania jego walorów geologicznych, geoturystycznych i rekreacyjnych

Antczak J., Krzeczyńska M., Wierzbowski A., Woźniak P.

Prace Komisji Krajobrazu Kulturowego

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2014

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nr 26

37--43

PL

Kamieniołom Kowalskiego w Wieluniu jest jednym z ważniejszych obiektów poeksploatacyjnych w pasie Jury Polskiej pod względem potencjału naukowego i edukacyjnego. Można w nim zobaczyć rzadko dostępne na powierzchni skały z pogranicza jury środkowej i górnej, które formowały się w morskim środowisku około 165 -160 mln lat temu. Kamieniołom ten odegrał też istotne znaczenie w historii kształtowania się miasta, bowiem właśnie stąd pochodził charakterystyczny twardy, żółty kamień (geza), z którego powstały jego najstarsze, średniowieczne budowle. Przemysłowej eksploatacji w kamieniołomie Kowalskiego zaprzestano w latach 60. XX w. Walory przyrodnicze kamieniołomu oraz jego położenie dały początek idei stworzenia w nim parku łączącego rekreację z interdyscyplinarną i interaktywną edukacją wysuwającą na pierwszy plan zagadnienia geologiczne. Projekt zmierza do ukazania Wielunia, jako północnych „wrót” Jury Polskiej, atrakcyjnego turystyczne regionu pomiędzy Wieluniem, Częstochową, a Krakowem.

EN

The Kowalski’s quarry at Wieluń is one of the most important post-exploited objects in the Polish Jura area both from its scientific and educational potentials. It shows the rocks rarely accessible on the surface from the transition of the Middle and Upper Jurassic which originated about 165-155 millions of years ago in sea environment. The quarry played an important role in development of Wieluń because it yielded the characteristic hard yellow-coloured rock (geizas) being the rough material for construction of the town. The industrial exploitation in the quarry was checked in sixties of the twenty century. The natural value of the quarry and its location gave the assumption for its treatment as a place for the future park foundation where the interdisciplinary and interactive education with special attention to geology could be realized. The project is aimed at accentuation of the position of the Wieluń Town as the northern “gate” of the Polish Jura – the attractive touring region.

14

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.

15

Aromatic hydrocarbons from the Middle Jurassic fossil wood of the Polish Jura

Smolarek J., Marynowski L.

Contemporary Trends in Geoscience

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2013

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Vol. 2, iss. 1

82--90

EN

Aromatic hydrocarbons are present in the fossil wood samples in relatively small amounts. In almost all of the tested samples the dominating aromatic hydrocarbon is perylene and its methyl and dimethyl derivatives. The most important biomarkers present in the aromatic fraction are dehydroabietane, siomonellite and retene, compounds characteristic for conifers. The distribution of discussed compounds is highly variable due to such early diagenetic processes affecting the wood as oxidation and the activity of microorganisms. MPI1 parameter values (methylphenanthrene index) for the majority of the samples are in the range of 0.1 to 0.5, which results in the highly variable values of Rc (converted value of vitrinite reflectance) ranging from 0.45 to 0.70%. Such values suggest that MPI1 parameter is not useful as maturity parameter in case of Middle Jurassic ore-bearing clays, even if measured strictly on terrestrial organic matter (OM). As a result of weathering processes (oxidation) the distribution of aromatic hydrocarbons changes. In the oxidized samples the amount of aromatic hydrocarbons, both polycyclic as well as aromatic biomarkers decreases.

16

Bulk geochemical data of fossil wood from the middle jurassic clays of Poland

Smolarek J.

Contemporary Trends in Geoscience

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2012

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Vol. 1, iss. 1

71--80

EN

Macroscopic observations, microscopic studies and literature data revealed that Middle Jurassic wood from Częstochowa area has a different state of preservation, and various types and degrees of mineralization and oxidation. Obtained results of organic matter fractionation illustrate a clear domination of polar fraction in the obtained extracts revealing low thermal maturity stage. Total organic carbon (TOC) values for analysed samples are in a wide range from 1.06% to 68.50%. The highest amount of TOC were measured in not or poorly mineralized wood samples but most of them are mineralized wood fragments, showing the TOC values in the range of 2% - 10%. Percentage content of carbonate in fossil wood constitute in a wide range from less than 1% CaCO3 to above 85% CaCO3. The resulting percentage of the total sulfur content is very varied and do not show convergence with other data such as TOC, carbonate content, etc and is most probable connected with pyritisation range. Unlike the Middle Jurassic clay samples, where long-chain and short-chain n-alkanes occur in similar concentrations, in wood samples always short-chain n-alkanes dominated, in the range from 15 to 23 carbon atoms in molecule. The values of the CPI are generally higher than 1 which indicates the contribution of organic matter derived from higher plant waxes, which are characteristic of e.g. needles from gymnosperm plants. Under the influence of postdiagenetic oxidation in mineralized wood samples distribution of n-alkanes is changing. Diaster-13(17)-enes with 28 and 29 carbon atoms in molecule are present in the wood samples, while those with 29 atoms strongly prevail.

PL

Makroskopowe obserwacje, mikroskopowe badania i dane literaturowe wykazały, że środkowojurajskie drewno z okolic Częstochowy ma różny stan zachowania oraz różne rodzaje i stopień mineralizacji oraz utlenienia. Uzyskane wyniki rozdziału frakcyjnego pokazują wyraźną przewagę frakcji polarnej w badanych ekstraktach. Wartości TOC dla badanych próbek wahają się w szerokim zakresie od 1,06% do 68,50 %. Największa ilość TOC występuje w nie zmineralizowanych lub słabo zmineralizowanych próbkach drewna. Większość próbek to zmineralizowane fragmenty drewna, pokazując wartości TOC w zakresie od 2% - 10%. Zawartość procentowa węglanów w badanych próbkach znajduje się w szerokim zakresie od mniej niż 1% CaCO3 do ponad 85% CaCO3. Procentowa zawartość siarki całkowitej jest bardzo zróżnicowana i nie wykazuje zbieżności z innymi danymi, takimi jak TOC czy zawartość węglanów, itp. W odróżnieniu od środkowojurajskich iłów, gdzie długołańcuchowe i krótkołańcuchowe n-alkany występują w podobnych stężeniach , w próbkach drewna zawsze przewyższają n-alkanów krótkołańcuchowe, występujące w zakresie od 15 do 23 atomów węgla w cząsteczce. Wartości wskaźnika CPI są generalnie wyższe niż 1, co wskazuje na udział materii organicznej pochodzącej z wosków roślin wyższych. Pod wpływem post-diagenetycznego utleniania zmineralizowanych próbek drewna zmienia się dystrybucja n-alkanów. W badanych próbkach obecne są diaster-13 (17)-enes o 28 i 29 atomów węgla w cząsteczce, natomiast te o 29 atomów znacznie przeważają.

17

Sedimentology and ichnology of Bathonian (Middle Jurassic) ore-bearing clays at Gnaszyn, Kraków-Silesia Homocline, Poland

Leonowicz P.

Acta Geologica Polonica

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2012

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Vol. 62, no. 3

281-296

EN

The lithology, sedimentary structures and trace fossil association from the Bathonian organic-rich mudstones from Kraków-Silesia Homocline (SW Poland) are described and a preliminary interpretation of the palaeoenvironment is presented. The ore-bearing clays exposed in the Gnaszyn clay-pit are developed as dark grey claysilt deposits with a few horizons of sideritic concretions. Sedimentological analysis has revealed that these deposits originated in the offshore part of a marine basin, below the fair weather wave base. Relict parallel lamination suggests that the predominant mechanism of deposition was quiet settling from suspension. However, locally preserved storm deposits indicate that the sea bottom was affected by offshore flows, deriving coarser material from the nearshore area. The degree of bioturbation is high but the diversity of the trace-fossil association is low. It consists mainly of Chondrites, Trichichnus, pyritized burrows and less common Palaeophycus. Other traces, including Thalassinoides, Planolites, Taenidium and some undetermined burrows, occur mainly in the lower part of the succession. This ichnoassociation combines features of distal Cruziana and Zoophycos ichnofacies, suggesting poor oxygenation of the bottom sediment. Temporary improvements in bottom oxygenation, linked with more intense mixing of water during major storms, resulted in the more diverse trace fossil suite that is found in some intervals of the succession.

18

Palynofacies from Bathonian (Middle Jurassic) ore-bearing clays at Gnaszyn, Kraków-Silesia Homocline, Poland, with special emphasis on sporomorph eco-groups

Gedl P., Ziaja J.

Acta Geologica Polonica

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2012

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Vol. 62, no. 3

325-349

EN

The palynological organic matter of dark clays from Bathonian ore-bearing clays exposed at Gnaszyn (Częstochowa, Kraków-Silesia Homocline, Poland) consists of high proportions of land-derived particles; aquatic elements (mainly dinoflagellate cysts) are comparatively rare. Terrestrial particles include black opaque phytoclasts, dark brown phytoclasts, cuticle remains and subordinate sporomorphs. The latter are represented by eighty-four taxa of spores and pollen grains. They represent various groups of plants, including Bryophyta, Sphenophyta, Lycophyta, Pteridophyta, Pteridospermophyta, Cycadophyta or Ginkgophyta and Coniferophyta. The most frequent sporomorphs in almost all samples from Gnaszyn are Callialasporites (Araucariaceae), Cerebropollenites and Perinopollenites elatoides (Taxodiaceae) pollen grains, fern spores with triradiate tetrad mark, bisaccate pollen grains belonging to conifers (Pinaceae or Podocarpaceae) and also to Pteridospermophyta. Quantitative analysis of the palynofacies shows fluctuations of particular element ratios, which correlate with lithology. Clay intervals that contain siderite concretion levels yielded lower amounts of cuticles in relation to sporomorphs (mainly pollen grains) and dinoflagellate cysts. Intervals of monotonous clays and silts are characterized by a higher ratio of cuticles in relation to other elements, especially dinoflagellate cysts. Also, quantitative analysis of the sporomorphs shows changes in frequency of the representatives of various plant communities, which coexisted during the Jurassic: Upland, Lowland, River, Pioneer, Coastal and Tidally-influenced. These changes might have reflected sealevel fluctuations, which affected vegetation growing on adjacent land. However, the dominance of Callialasporites pollen grains, which belong to the Coastal community, indicates that the Gnaszyn assemblage was mainly influenced by the seashore vegetation. The high frequency of Araucariaceae pollen grains and the presence of ferns representing the Osmundaceae, Cyatheaceae, Dicksoniaceae, Schizeaceae, Gleicheniaceae and Matoniaceae indicate a warm climate without large seasonal amplitudes during the deposition of the Gnaszyn succession.

19

Palaeoenvironmental interpretation of echinoderm assemblages from Bathonian ore-bearing clays at Gnaszyn (Kraków-Silesia Homocline, Poland)

Boczarowski A.

Acta Geologica Polonica

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2012

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Vol. 62, no. 3

351-366

EN

This paper presents the results of an investigation into the variability of echinoderm assemblages from Bathonian ore-bearing clays from Gnaszyn. Remains of Crinoidea, Asteroidea, Ophiuroidea, Echinoidea, and Holothuroidea have been studied from 38 rock samples. The most common echinoderms represented are the crinoids Balanocrinus berchteni and Chariocrinus andreae and a few species of the holothurian genera Priscopedatus, Calclamna, Staurocaudina, Eocaudina, Achistrum, Theelia and Hemisphaeranthos. The echinoderms from Gnaszyn show various life strategies: benthic or epibenthic forms, sessile sestonophages (Crinoidea), motile macrophages (Asteroidea) and detritivores (Asteroidea, Ophiuroidea, Echinoidea), infaunal and epifaunal detritus feeders, sediment feeders or rake-feeders (Holothuroidea). Their presence suggests well oxygenated and presumably relatively cold bottom marine waters. The parts of the Gnaszyn section around concretion horizons and characterized by the ubiquitous occurrence of the holothurian Theelia and echinoids were deposited during phases of optimal living conditions with sufficient influx of plant detritus and good oxygenation of the sea bottom. These parts commonly host echinoderm associations dominated by crinoid remains, which occasionally are still articulated (or disarticulated but remaining intact) - this points to a quiet environment with normal oxygenation of the bottom waters but anaerobic/dysaerobic conditions in the sediment.

20

Organic-walled dinoflagellate cysts from the Bathonian ore-bearing clays at Gnaszyn, Kraków-Silesia Homocline, Poland - a palaeoenvironmental approach

Gedl P.

Acta Geologica Polonica

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2012

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Vol. 62, no. 3

439-461

EN

A succession of Middle-Upper Bathonian (Subcontractus.Retrocostatum zones) ore-bearing clays exposed at Gnaszyn has been investigated for the presence of dinoflagellate cysts. The assemblages are dominated by Ctenidodinium. However, analysis of diversity shows some subtle differences throughout the succession, possibly related to the palaeoenvironmental conditions in the photic zone. Impoverished assemblages, dominated by Ctenidodinium, occur mainly in monotonous muddy intervals. More diverse assemblages, albeit also dominated by Ctenidodinium, occur in intervals which contain siderite concretion levels. The taxonomic composition of the former assemblage seems to reflect slightly restricted conditions in the photic zone, possibly related to a minor reduction in salinity and/or increase in nutrient availability. More diverse dinoflagellate cyst assemblages reflect periods of less intense terrigenous influx and relatively higher, possibly normal, salinity. These changes were possibly caused by variable intensity of freshwater influx into the basin, controlled by sea-level fluctuations. Sea-level changes may be related to migrations of Tethyan water masses, which were probably partly responsible for the composition of the dinoflagellate cyst assemblages.