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Number of results: 14
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Abstract

The correlation of the Coniacian and Santonian chalks of the Anglo-Paris Basin is described on the basis of detailed lithological logs and extensive records of macrofossils and microcrinoids. In the almost complete absence of ammonites, inoceramid bivalves afford the highest resolution correlation of these stages in chalks, but their value here is limited by the absence of key genera and species, most notably in the Upper Coniacian and middle and Upper Santonian. Echinoids and other macrofossils (brachiopods, stalked crinoids, belemnites) have proved useful, but many are long-ranging or uncommon. Some marker beds, including flints and marl seams, provide useful correlations across the basin, but are locally absent. For the Upper Santonian, the stemless benthonic crinoids Uintacrinus and Marsupites provide high-resolution correlation, both within the basin and to other regions. The successions on the basin margins, in the far north of France (Nord, Pas de Calais) and the southwest (Touraine) are condensed and yield ammonites in association with important inoceramid species. The controls on sedimentation caused by sea-level changes are evaluated on a basinal and global scale, most especially for the Upper Santonian.
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Authors and Affiliations

Andrew Scott Gale
1

  1. School of the Environment, Geography and Geosciences, University of Portsmouth, Burnaby Building,Burnaby Road, Portsmouth PO13QL, UK; Department of Earth Sciences, The Natural History Museum, Cromwell Road, London SW75BD, UK
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Abstract

Ammonites, chiefly from the Upper Turonian Prionocyclus germari Zone, the Lower Coniacian part of the Forresteria (Harleites) petrocoriensis Zone, and the Lower Coniacan Peroniceras (Peroniceras) tridorsatum Zone from the Czech Republic are figured and described, including classic material originally described by Fritsch (1872–1898) and Jahn (1892, 1896). In all, 25 species are recognised, including two, Pseudojacobites sp. and Muniericeras sp., that represent genera previously not known from the area.
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Authors and Affiliations

William James Kennedy
1
Herbert Summesberger

  1. Oxford University Museum of Natural History, Parks Road, Oxford, OX13PW and Department of Earth Sciences, South Parks Road, OX13AN UK
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Abstract

We propose a spit bar setting as the possible palaeoenvironment of the basal Late Cretaceous transgressive sequence in NW Bohemia. A new Cenomanian transgression model for the Bohemian Basin is also proposed. The uppermost Devět Křížů Sandstone, which has been conventionally referred to the Bohdašín Formation, probably represents the middle or lower upper Cenomanian (Upper Cretaceous), not the Triassic as previously supposed. We assume that this controversial unit was deposited before the main latest Cenomanian–early Turonian transgression. The spit bars were likely overgrown by vascular plants during their emergence in the late Cenomanian, and then inundated during the latest Cenomanian and early Turonian transgressive phases. The studied deposits had been intensively bioturbated, and the cf. Taenidium suite was recognized for the first time in them alongside the Thalassinoides assemblage (T. paradoxicus, T. suevicus, Thalassinoides isp., cf. Thalassinoides), which are characteristic of the Scoyenia and Glossifungites ichnofacies, respectively. The bioturbated, rhizolith-bearing horizon was presumably a paleosol.
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Authors and Affiliations

Alina Chrząstek
1
Jurand Wojewoda
2

  1. Institute of Geological Sciences, University of Wrocław, Maksa Borna 9, 50-204 Wrocław, Poland
  2. Faculty of Geoengineering, Mining and Geology, Wrocław University of Science and Technology,Na Grobli 15, 50-421 Wrocław, Poland
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Abstract

An integration of palynomorph and palynofacies data from the Shushan-1X well is used to infer the paleoenvironmental conditions of the Valanginian to Middle Cenomanian (Cretaceous) section of the western Shushan Basin, northern Egypt. The data obtained contribute significantly to the depositional history of the basin. The low diversity of dinoflagellate cyst assemblages, along with the dominance of land-derived spores and pollen, suggest restricted (marginal) marine environments, in contrast to their coeval representatives from the Tethyan Realm. Open marine (inner shelf) environments developed at a few horizons in the Dahab and Bahariya formations, partly contemporary with the global Aptian and Cenomanian eustatic cycles. These environments were relatively more offshore than those described in the eastern and southeastern parts of the basin. The study of total palynological organic matter (TPOM) has contributed largely to these established environmental settings. It has also allowed the recognition of redox (suboxic to anoxic) conditions and the impact of a large magnitude of terrigenous influence.
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Authors and Affiliations

Magdy Mahmoud
1
Amal Temraz
2
Abdel-Rahim Moawad
2
Miran Khalaf
3

  1. Geology Department, Faculty of Science, Assiut University, Assiut 71516, Egypt
  2. Geology Department, Faculty of Science, South Valley University, Qena 83523, Egypt
  3. Geology Department, Faculty of Science, Sohag University, Sohag 82524, Egypt
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Abstract

The serpulid tube worm Laqueoserpula reussi (Weinzettl, 1910), originally introduced as a gastropod named Burtinella(?) reussi, is described from the Upper Cenomanian and Lower Turonian of the Bohemian Cretaceous Basin. It had usually been confused with other species and genera before 2008. Comparison with specimens from the type locality of the type species of the genus Laqueoserpula Lommerzheim, 1979 confirms the affiliation of the Bohemian species to this genus. The simple prismatic (SP) ultrastructure of the tube wall of L. reussi agrees with an assignment to the tribe Serpulini Rafinesque, 1815. In the Upper Cretaceous, representatives of Laqueoserpula are exclusively found in nearshore deposits, where they are accompanied by a high diverse marine invertebrate fauna. By its compact, large and robust tube forming a spiral and extremely thick tube wall, L. reussi was well-adapted to live in nearshore high energy environments, where its tube could be encrusted by bryozoans, brachiopods and oysters, and infested by hydroids and borers.
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Authors and Affiliations

Manfred Jäger
1
Tomáš Kočí
2
Jan Sklenář
3
Kamil Zágoršek
4

  1. Lindenstrasse 53, 72348 Rosenfeld, Germany
  2. Ivančická 581, Praha 9 – Letňany, 199 00, Czech Republic; Department of Palaeontology, National Museum, Cirkusová 1740, 193 00 Praha 20 – Horní Počernice,Czech Republic
  3. Department of Palaeontology, National Museum, Cirkusová 1740, 193 00 Praha 20 – Horní Počernice,Czech Republic
  4. Department of Geography, Technical University of Liberec, Studentská 2, 461 17 Liberec, Czech Republic
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Abstract

The study focuses on the geochronology and correlation between loesses and glacial tills in the Vistula catchment in Poland, in an area covered by all Scandinavian ice-sheets and characterized by thick loess successions. The basis for this correlation was a litostratigraphic analysis of selected loess sites in the uplands, which are well-documented in the literature, and the occurrences of loess and loess-like deposits under the cover of glacial deposits in the lowland part of the Vistula catchment, characterized by a much sparser documentation. The nomenclature of loess horizons follows Maruszczak (2001) and Kukla (1987), but sometimes is significantly changed, according to modern Quaternary stratigraphical schemes. According to the analysis, accumulation of almost all loess horizons distinguished so far has been documented in the Pleistocene succession of the Vistula catchment: the oldest – lower (LNd), middle (LNs), and upper (LNg); older: lower (LSd), middle (LSs), and upper (LSg); and younger: lowest (LMn), lower (LMd), middle (LMs), and upper (LMg). In most cases loess accumulation took place in steppe-tundra conditions preceding the maximum ice-sheet development during the succeeding Scandinavian glaciations. For selected sites, the loess occurrence is presented in superposition to glacial tills and interglacial deposits. The distinguished loesses and glacial tills are tied to the stratigraphic schemes of the Pleistocene in Poland (Marks et al. 2016, 2019) and correlated with Ukrainian loess horizons (Łanczont et al. 2019).
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Authors and Affiliations

Jan Dzierżek
1
Leszek Lindner
1

  1. University of Warsaw, Faculty of Geology, Żwirki i Wigury 93, 02-089 Warszawa, Poland
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Abstract

This paper is a continuation of the previous one (Widera, 2024. Acta Geologica Polonica, 74 (1), e2). A new, alternative interpretation of the tectonic development of two lignite-rich deposits in the Lubstów and Kleszczów grabens in central Poland is presented. The maximum thickness of lignite mined from both deposits is >86 and >250 m, respectively. These grabens were selected for detailed tectonic analysis because syn-depositional or post-depositional tectonic uplift is undeniably evident. The current study focuses on the distinction between tectonic subsidence/uplift and autocompactional subsidence, and on the timing of their occurrence. Such a research approach allows for the presentation of new conceptual models of Cenozoic tectonic evolution during the formation of the third, very thick, Ścinawa lignite seam (ŚLS-3) and the second Lusatian lignite seam (LLS-2). As a result, it is shown here that the magnitude of both the downward and upward tectonic movements are significantly smaller than previously thought. This new interpretation is also confirmed by the low rank of lignite coalification and the net calorific value of the ŚLS-3 and LLS-2.
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Authors and Affiliations

Marek Widera
1
ORCID: ORCID

  1. Institute of Geology, Adam Mickiewicz University, Krygowskiego 12, 61-680 Poznań, Poland
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Abstract

In order to address the difficult problem of ball mill load identification during milling operation, the multi-scale fuzzy entropy algorithm is introduced into ball mill load identification and an innovative ball mill load identification method is proposed- the complete integrated empirical decomposition based on adaptive noise (CEEMDAN)-joint denoising with wavelet thresholding-multi-scale fuzzy entropy biased mean value (PMMFE) ball mill load identification method. Firstly, the vibration signals of ball mill bearings are denoised by the CEEMDAN-wavelet threshold joint denoising method and the analysis reveals that this method has obvious advantages over other denoising methods; secondly, the fuzzy entropy, multi-scale fuzzy entropy, and multi-scale fuzzy entropy deviation of denoised vibration signals are computed, the relationship between each entropy feature and the mill load is analysed in-depth and in an information-rich manner. Finally, the least squares support vector algorithm is used to identify the load of the feature vector. The analysis of the measured vibration signals reveals that the overall recognition rate of this method is 84.4%, which is significantly higher than that of other denoising methods and the combination of feature parameters, and the experiments show that the mill load recognition method based on CEEMDAN-wavelet thresholding-PMMFE is able to effectively identify the different loading states of ball mills.
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Authors and Affiliations

Lirong Yang
1
Hui Yang
2
ORCID: ORCID

  1. Jiangxi Mining and Metallurgical Engineering Research Center, China; School of Mechanical and ElectricalEngineering, Jiangxi University of Science and Technology, Ganzhou, Jiangxi Province, China
  2. School of Mechanical and Electrical Engineering, Jiangxi University of Science and Technology, Ganzhou,Jiangxi Province, China
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Abstract

Poland is among the top ten countries in the world in terms of lignite resources (including reserves). With respect to lignite mining, its position is even higher at sixth in the world, fourth in Europe and second in the European Union (EU). The role of lignite in the Polish energy mix is crucial because ~27% of electricity was generated in lignite-fired power plants in 2022. However, there are countries in Europe where the dependence on lignite is much greater and currently in the range of 40–96%. B oth the national and EU climate energy policy assumes the abandonment of lignite as a source of ‘dirty’ electricity within the next two decades. This ambitious goal is achievable but it may be threatened by the geopolitical situation. However, after 2040–2044, a large number of lignite deposits will remain in Poland. The deposits are well recognized and the detailed geology is well documented, with the estimated reserves intended for exploitation amounting to 5.8 Gt. These deposits, like the five which are currently mined, are stratigraphically diverse and characterized by a complex geology, representing different genetic types. In the context of a coal-free energy policy in the EU, the problem of the legal protection of lignite deposits remains. Thus, the question arises of what is next for Polish lignite deposits. They may be managed in the coming decades by using improved unconventional methods, such as in situ or ex situ gasification. Lignite deposits will constitute a strategic reserve in the event of a deep energy crisis caused by an unstable geopolitical situation. Finally, we suggest the urgent introduction of more precise legal changes that would protect at least part of the lignite resources in Poland for future generations.
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Authors and Affiliations

Marek Widera
1
ORCID: ORCID
Paweł Urbański
2
ORCID: ORCID
Sławomir Mazurek
2
ORCID: ORCID
Wojciech Naworyta
3
ORCID: ORCID

  1. Institute of Geology, Adam Mickiewicz University, Poznań, Poland
  2. Polish Geological Institute – National Research Institute, Warszawa, Poland
  3. Mining Engineering and Occupational Safety, AGH University of Science and Technology, Kraków, Poland
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Abstract

The economic importance, global market, primary resources and secondary sources of niobium are discussed in this paper. Niobium concentrate is the first commercial product of the enrichment process; however, the overwhelming majority of the niobium concentrate supply is processed into ferroniobium, which dominates international trade. In this form, niobium raw materials are used in the steel industry as an alloying agent (alloy additive). The production of \oxides and other compounds of niobium, such as carbides, alloys and metallic niobium are currently of much less commercial significance. The addition of a very small amount of niobium, of the order of 0.01%, changes the properties of steel fundamentally, increasing its strength, resistance to atmospheric factors or high temperatures, etc. The addition of niobium in other products also changes their properties, e.g. permanent magnets become superconductors. As a result, niobium is currently widely used around the world as a component of sustainable technologies, which has a large positive impact on the environment by reducing the energy and material consumption of the manufacturing processes. The increase in the spectrum of niobium applications in advanced technologies, considered to be the technologies of the future, means that the widely recognized critical importance of niobium continues to grow. It can be assumed that the war between Ukraine and Russia will cause significant disturbances in the global metals market, including that for niobium.
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Authors and Affiliations

Andrzej Gałaś
1
ORCID: ORCID
Mariusz Krzak
2
ORCID: ORCID
Jarosław Szlugaj
1
ORCID: ORCID

  1. Mineral and Energy Economy Research Institute, Polish Academy of Sciences, Kraków, Poland
  2. AGH University of Krakow, Faculty of Geology, Geophysics and Environmental Protection, Kraków, Poland
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Abstract

This work aimed to verify forecasts of temperature and mineralization of the Lower Jurassic and Lower Cretaceous waters in the Polish Lowlands, based on new geological information. In the first part of the articles series, entitled Verification of geothermal conditions in the Polish Lowlands based on data from new drilling performed in the years 2000–2022, an analysis of geothermal conditions is presented, while this work focuses on hydrogeochemical parameters, such as temperature in the top of formations and water mineralization. For this purpose, data from the Central Geological Database (CBDG), the Central Bank of Hydrogeological Data – HY DRO Bank, and from previously published scientific and research works were used. In the years 2000–2023, twenty-four exploration wells with a depth exceeding 1000 m below ground level were drilled and documented in the Polish Lowlands, providing information on the temperature and mineralization of waters taken from the Lower Jurassic or Lower Cretaceous formations. The assessment of spatial changes, as in the first part of the work, was performed with the use of QGIS Desktop 3.24.1 software, which is geoinformation software (GIS ) that allows viewing, editing, and analyzing spatial data and the creation of maps. The presented analysis made it possible to make a spot, local correction of the projected course of the isoline in relation to the maps published earlier in the Atlas of geothermal resources in the Polish Lowlands. Mesozoic Formations developed in 2006, edited by Wojciech Górecki.
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Authors and Affiliations

Wiesław Bujakowski
1
ORCID: ORCID
Piotr Zacharski
2
Barbara Tomaszewska
3
ORCID: ORCID
Magdalena Tyszer
1
ORCID: ORCID
Karol Pierzchała
1
Bogusław Bielec
1
ORCID: ORCID
Leszek Pająk
4
ORCID: ORCID
Beata Kępińska
1
ORCID: ORCID
Krystian Szczepański
2

  1. Mineral and Energy Economy Research Institute, Polish Academy of Sciences, Kraków, Poland
  2. Institute of Environmental Protection – National Research Institute, Warszawa, Poland
  3. Mineral and Energy Economy Research Institute, Polish Academy of Sciences, Kraków, Poland; AGH University of Science and Technology, Kraków, Poland
  4. Mineral and Energy Economy Research Institute, Polish Academy of Sciences, Kraków, Poland; AGH Universityof Science and Technology, Kraków, Poland
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Abstract

Scanning electron microscopy (SEM) enables the obtaining of high-resolution images of sample surfaces by recording secondary electrons (SE) or backscattered electrons (BSE) characterized by depth of field and high resolution. Observations using scanning electron microscopy are widely used in many fields of science. The authors show that scanning electron microscopy is also one of the key technique used in the study of the metallurgical slags components. The research was performed for three types of slag following the production of Zn and Pb collected from an old dump in Ruda Śląska – Bykowina. The slag components were identified, morphology and chemical composition of the crystalline phases were characterized and the chemical composition of glaze was determined. Based on observations using secondary electrons, two areas with diverse morphology were identified in slag resulting from the production of cast iron: fragments with coarse structure and visible crystallites of phase components, and a vitrified material with a smooth, non-fractured surface and numerous regular- and round-shaped pores. It was found that in the surroundings of the dominant glaze (rich mainly in Si, Ca and Al) in all types of slags, well-developed crystals of phase components can be distinguished: in slag no. 1, these are Fe-Mg silicates; in slag no. 2, they are aluminosilicates of Ti and K; in slag no. 3, the presence of fine needle-shaped crystals containing Al and Si was found, which indicates the presence of mullite. During the storage in the dumping ground, numerous secondary minerals crystallize in the pores of the slag. Pores are the remains of the degassing of the slag melt during its cooling – hematite and barite were identified among them.
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Authors and Affiliations

Iwona Jonczy
1
ORCID: ORCID
Krzysztof Filipowicz
2
ORCID: ORCID

  1. Silesian University of Technology, Faculty of Mining, Safety Engineering and Industrial Automation, Gliwice, Poland
  2. Silesian University of Technology, Faculty of Mining, Safety Engineering and Industrial Automation, Gliwice
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Abstract

This article aims to identify and assess the impact of capital structure factors on financing strategies of mining industry enterprises in Central and E astern E uropean (CEE ) countries in comparison to W estern E uropean (WE ) Union countries. T he research contributes to determining which of the main theories of capital structure best describes the financial strategies employed in the examined sector. T he analysis encompasses mining companies from eight WE and four CEE countries, utilising panel data models with information spanning from 2000 to 2020. T he study covers various firm-specific variables commonly employed in similar research, along with the effects of country and year.
The main findings indicate a significant similarity in both the capital structure and the influence of the analysed factors on leverage across the two regions. This homogeneity is attributed to the industrial specificity of the mining sector, which appears to supersede country-specific or firm-size specific features. Moreover, examining the impact of variables on capital structure considering different debt maturity terms reveals that the financial strategies of the analysed companies align with the pecking order and agency theory of capital structure. T his suggests that mining companies predominantly rely on internal financing, viewing debt primarily as a tool to discipline managers. Due to data limitations in the employed BACH database, the study does not encompass all EU countries, highlighting the potential for further research incorporating other regions. T he identified similarities in capital structure, along with the impact of various factors, provide insights for financial decision-makers in mining firms, and investors operating in both CEE and WE EU countries. Str
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Authors and Affiliations

Magdalena Gostkowska-Drzewicka
1
ORCID: ORCID
Julia Koralun-Bereźnicka
1
ORCID: ORCID

  1. University of Gdańsk, Poland
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Abstract

In contrast to the western part of the Lower Silesia, information about the basalt-derived weathering crusts occurring in the Opole region is rather limited. However, in 2018, significant volumes of such regolith (about 20,000 m3) were discovered during development works in the NW part of the Rutki Quarry near Niemodlin. This weathering crust is rich in clay minerals and represents a smectite- kaolinite mixture with some halloysite, the latter being a poorly ordered member of the kaolinite group. The minerals of the smectite group contain in their interlayer spaces bivalent cations (calcium and magnesium), which is the most often case in the nature. The mineral composition of the regolith mass is supplemented by iron-containing phases, i.e. goethite and magnetite, and traces of phosphate mineral – crandallite. A significant amount of clay minerals, particularly those belonging to the smectite group and halloysite, results in high value of the specific surface area (up to 100 m2/g) of the studied crust. Such favorable property of the crust makes it a promising sorptive raw material that can be applied, even in an unprocessed form, for waterproofing. It must be emphasized that the sorption properties of basalt weathering crusts were noticed some centuries ago in the western part of Lower Silesia, where medicine called terra sigillata was produced from them. Moreover, the crust from Rutki was also used in the XIXth century, in a ceramic manufacture located in nearby Tułowice, where the so-called “Silesian black porcelain” was produced.
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Authors and Affiliations

Piotr Wyszomirski
1
ORCID: ORCID
Tadeusz Szydłak
1
ORCID: ORCID
Tomasz Zawadzki
2
Marcin Baranowski
2

  1. AGH University of Krakow, Poland
  2. Kopalnie Odkrywkowe Surowców Drogowych SA, Niemodlin, Poland

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