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Neptunian dykes penetrating the Lower Jurassic Dudziniec Formation in the autochthonous High-Tatric succession, Tatra Mountains, Western Carpathians, Poland

Łuczyński P., Jezierska A.

Acta Geologica Polonica

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2018

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Vol. 68, no. 4

555--570

EN

The Lower Jurassic to Aalenian carbonate-clastic Dudziniec Formation exposed in the autochthonous unit of the Tatra Mountains (Kościeliska Valley) hosts neptunian dykes filled with various deposits. The development of the fissures took place in multiple stages, with the same fractures opening several times, as is indicated by their architecture, occurrence of internal breccias and arrangement of the infilling sediments. Various types of internal deposits were derived in a different manner and from different sources. Fine carbonate sediments, represented by variously coloured pelitic limestones, calcilutites and fine calcarenites, most probably come from uplifted and corroded carbonate massifs (possibly from the allochthonous units of the High-Tatric succession). Products of weathering, both in dissolved form and as small particles, were washed into the sedimentary basin of the autochthonous unit, and redeposited within the dykes. The sandy varieties of the infillings, represented by red, ferruginous calcareous sandstones, come directly from the host rocks or from loose sediments present on the sea bottom at the time of fracturing. The most probable age of the infilling sediments is Sinemurian to Pliensbachian. The occurrence of dykes of this age is yet another feature confirming that the sedimentary development of the Lower Jurassic sandy-carbonate facies in the autochthonous unit was strongly influenced by synsedimentary tectonic activity, such as block-faulting.

2

Modeling of warm-keeping process with hot air in steam turbines

Łuczyński P., Többen D., Wirsum M., Mohr W.F.D, Helbig K.

Journal of Power Technologies

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2017

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Vol. 97, nr 5

416--428

EN

Steam turbines in conventional power plants have to deal with an increasing number of start-ups due to the high share of fluctuating power input in renewable power generation. As a result, the development of new methods for flexibility improvements - such as reductions in start-up time and the effects these start-ups have on turbine lifetime - have become increasingly important. In pursuit of this objective, General Electric has developed a concept for both the pre-warming and warm-keeping of a high-pressure (HP) / intermediate-pressure (IP) steam turbine with hot air: hot air is passed through the turbine while the turbine is rotated by the turning engine. Due to the high impact of transient flow phenomena on heat transfer during turbine warm-keeping operations, the reliable modeling of the time-dependent temperature distribution within thick-walled components is required as a tool for the optimization of these operations. Due to the extremely high computational effort required for conventional transient Conjugate Heat Transfer (CHT) simulations, alternative fast calculation approaches must be developed. The applied methodology for modeling warm-keeping turbine operations with hot air is presented in this paper. Furthermore, the key modeling steps have been analyzed. A fast transient CHT simulation approach called the Equalized Timescales (ET) method was developed to investigate heat transfer in the fluid and blades. Moreover, the setup of ET simulations was optimized with regard to accuracy and computing time. As a result, several operating points characterizing the turbine warm-keeping operational range were calculated for a single stage model. A sensitivity analysis regarding the heat transfer between fluids and solids was conducted to identify the most relevant surfaces. The ET method was then expanded to a numerical 3-stage turbine model in order to determine a HTC characteristic map for heat transfer in warm-keeping operations. This enables fast calculation of heat transfer rates and, consequently, computationally efficient determination of temperature distribution in warm-kept steam turbines. For comparison, the distribution of HTC was additionally calculated for one operating point of a 5-stage turbine model. Finally, the contact heat transfer in blade roots, which is believed to have a high impact on the temperature distribution of the rotor, was experimentally assessed in a test rig. The description of the test rig and the methodology of determination of the thermal contact resistance (TCR), as well as the impact of TCR on the temperature distribution in the rotor are presented.

3

Jurassic unconformities in the High-Tatric succession, Tatra Mountains, Poland

Jezierska A., Łuczyński P.

Geological Quarterly

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2016

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Vol. 60, No. 2

273--290

EN

During the Triassic/Jurassic boundary interval and in the Jurassic, the Triassic carbonate platforms occupying the northern shelf of the Western Tethys were subjected to disintegration. Record of these processes in the Alpine-Carpathian area is incomplete and contains a number of stratigraphic gaps. In the High-Tatric succession of the Tatra Mountains (Central Western Carpathians) stratigraphic gaps expressed by unconformity surfaces occur between the Triassic and the Middle Jurassic. In particular areas, the Triassic is directly overlain by the Dudziniec Formation (Sinemurian-Bajocian), the Smolegowa Formation (Bajocian), the Krupianka Formation (Bathonian) or the Raptawicka Turnia Formation (Callovian-Hauterivian). The occurrence of Bajocian and Bathonian deposits is limited to isolated lenticular bodies or to infillings of neptunian dykes penetrating the Triassic. Spatial relations between particular Jurassic lithosomes and the occurrence of stratigraphic gaps between particular units allow discerning four main unconformities. In the stratigraphical order these are: base of the Dudziniec Format ion (erosional unconformity), base of the Smolegowa Formation (penacordance or parat conformity), base of the Krupianka Format ion (erosional unconformity) and base of the Raptawicka Turnia Formation (drowning unconformity). Following episodes of erosion modified the previously developed unconformity surfaces, which resulted in complex modern architecture of the Triassic/Jurassic contact, as well as between particular Jurassic formations.

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Carbonate-clastic sediments of the Dudziniec Formation in the Kościeliska Valley (High-Tatric series, Tatra Mountains, Poland) : role of syndepositional tectonic activity in facies development during the Early and Middle Jurassic

Jezierska A., Łuczyński P., Staśkiewicz A.

Geological Quarterly

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2016

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Vol. 60, No. 4

869--880

EN

Sediments of the Dudziniec Formation (Lower Jurassic – Aalenian) outcropping in the Kościeliska Valley (autochthonous unit of the High-Tatric series) are represented by a range of mixed carbonate-clastic deposits. Seven lithofacies have been distinguished based on lithology, sedimentary structures, colour and composition of intra- and extraclasts, with sandstones and crinoidal limestones as end members of a continuous spectrum of facies. The study area represents a shallower part of the sedimentary basin located in the vicinity of source areas, as compared to the Chochołowska Valley region located in the west. Facies characteristics and distribution were controlled mainly by synsedimentary tectonic activity, with sandy varieties representing periods of faulting with enhanced influx of extraclasts, and with crinoidal limestones corresponding to intervals of relative tectonic stability. Such influence of synsedimentary tectonics on the deposition in the Early Jurassic strongly resembles the Middle Jurassic development in the High-Tatric area. Neptunian dykes cutting the Dudziniec Formation, and most probably filled by Lower Jurassic sediments, are yet another indication of tectonic instability of the area in the Early Jurassic.

5

Recent studies on the Silurian of the western part of Ukraine

Łuczyński P., Skompski S., Kozłowski W.

Acta Geologica Polonica

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2016

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Vol. 66, no. 3

281--297

EN

The paper summarises the effects of recent studies carried out by a team from the Department of Historical and Regional Geology of the Faculty of Geology, University of Warsaw on the upper Silurian of Podolia (western part of Ukraine). The sedimentary history of the Silurian succession of Podolia is characterised by its cyclic pattern, with shallowing-upward cyclothems. In the traditional interpretation, the occurrence of stromatoporoid beds within each cyclothem marks the deepest (or most open-marine) sedimentary environment within the cycle. According to the results of recent studies, their occurrence is connected rather with a relatively shallow-water environment and with high energy phenomena. A substantial reinterpretation of the main sedimentary processes governing the deposition and facies distribution on the shelf is presented. Particularly, there are recognised and described high-energy sedimentary events repeatedly punctuating the generally calm sedimentation that prevailed in the lagoonal settings, some of which are interpreted as tsunami induced. Further perspectives for studies on the Silurian successions of Podolia are also discussed. The main problem is the precise correlation of particular sections that are scattered over vast distances and developed in similar facies associations.

6

Regressive-transgressive cyclothem with facies record of the re-flooding window in the Late Silurian carbonate succession (Podolia, Ukraine)

Łuczyński P., Kozłowski W., Skompski S.

Acta Geologica Polonica

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2015

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Vol. 65, no. 3

297--318

EN

The term “re-flooding window” was recently proposed as a time-interval connected with the transgressive stage of present day peri-reefal development. In the analysis presented here, a fossil record of a re-flooding window has been recognized. Nine Late Silurian carbonate sections exposed on the banks of the Dnister River in Podolia (Ukraine) have been correlated base on bed-by-bed microfacies analysis and spectral gamma ray (SGR) measurements. Correlated were sections representing settings ranging from the inner part of a shallow-water carbonate platform to its slope, through an organic buildup. The reconstructed depositional scenario has been divided into six development stages, with the first three representing a regressive interval and the latter three a transgressive interval of the basin’s history. The re-flooding window has been identified at the beginning of a transgressive part of the succession. Surprisingly, it is characterized by an extremely fast growth of a shallow, tide-dominated platform and by deposition of calciturbiditic layers in a more basinal area. The interpreted succession is a small-scale model illustrating the reaction of carbonate depositional sub-environments to sea level changes and determining the facies position of the stromatoporoid buildups within the facies pattern on a Silurian shelf. The use of SGR analyses in shallow water, partly high-energy, carbonate facies, both for correlation purposes and for identifying depositional systems, is a relatively new method, and thus can serve as a reference for other studies of similar facies assortment.

7

Stromatoporoid beds and flat-pebble conglomerates interpreted as tsunami deposits in the Upper Silurian of Podolia, Ukraine

Łuczyński P., Skompski S., Kozłowski W.

Acta Geologica Polonica

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2014

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Vol. 64, no. 3

261--280

EN

Tsunami deposits are currently a subject of intensive studies. Tsunamis must have occurred in the geological past in the same frequency as nowadays, yet their identified depositional record is surprisingly scarce. Here we describe a hitherto unrecognized example of probable palaeotsunamites. The Upper Silurian (Pridoli) carbonate succession of Podolia (southwestern Ukraine) contains variously developed event beds forming intercalations within peritidal deposits (shallow water limestones, nodular marls and dolomites). The event beds are represented by stromatoporoid and fine-grained bioclastic limestones, in some places accompanied by flat-pebble conglomerates. The interval with event beds can be traced along the Zbruch River in separate outcrops over a distance of more than 20 km along a transect oblique to the palaeoshoreline. The stromatoporoid beds have erosional bottom surfaces and are composed of overturned and often fragmented massive skeletons. The material has been transported landward from their offshore habitats and deposited in lagoonal settings. The flat-pebble conglomerates are composed of sub-angular micritic clasts that are lithologically identical to the sediments forming the underlying beds. Large-scale landward transport of the biogenic material has to be attributed to phenomena with very high energy levels, such as tropical hurricanes or tsunamis. This paper presents a tsunamigenic interpretation. Morphometric features of redeposited stromatoporoids point to a calm original growth environment at depths well below storm wave base. Tsunami waves are the most probable factor that could cause their redeposition from such a setting. The vastness of the area covered by parabiostromal stromatoporoid beds resembles the distribution of modern tsunami deposits in offshore settings. The stromatoporoid beds with unsorted stromatoporoids of various dimensions evenly distributed throughout the thickness of the beds and with clast-supported textures most probably represent deposition by traction. In some sections, the stromatoporoids are restricted to the lowermost parts of the beds, which pass upwards into bioclastic limestones. In this case, the finer material was deposited from suspension. The coexistence of stromatoporoid beds and flat-pebble conglomerates also allows presenting a tsunami interpretation of the latter. The propagating tsunami waves, led to erosion of partly lithified thin-layered mudstones, their fragmentation into flat clasts and redeposition as flat-pebble conglomerates.

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Problem tsunamitów. Dlaczego tak mało jest kopalnych osadów tsunami?

Łuczyński P.

Przegląd Geologiczny

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2012

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Vol. 60, nr 11

598–-604

EN

Tsunami is a common phenomenon and one of the most dangerous natural hazards of the modern world. Taking into account the relative high frequency of tsunamis in historical times, we can expect accordingly rich geological records of similar events from fossil formations. However, palaeotsunami deposits are surprisingly rare, mainly because of the difficulty of discerning them from sediments formed by other processes, e.g. storms. Part of the problem lies in the definition of tsunamite, which refers only to the triggering process, and in a different approach while discerning modern and fossil tsunamites. Modern tsunamites are identified by connecting the deposits to a particular historical tsunami event, even if they contain no diagnostic sedimentological features - an approach, which cannot be applied to fossil formations. This can lead to an impression that modern tsunami deposits are much more common than their fossil counterparts, which in turn suggest great intensification of tsunami events in historical times. Lately, a great number ofpapers have been published on sedimentary effects of modern tsunamis. The studies concentrated on land and near-shore areas. Many authors point out that the sedimentary record left by tsunami is commonly surprisingly mean and with a very low preservation potential. When interpreting fossil successions, the most important features that might indicate their tsunamite genesis are: mixing of material derivedfrom various facial zones, evidence of deep erosion and long transport, and association with other symptoms of seismic activity. The stromatoporoid biostromal accumulations in the Upper Silurian ofPodolia are presented here as possible palaeotsunamite deposits. Thick layers of redeposited stromatoporoids within fine-grained peritidal deposits are interpreted as an effect of onshore transport of this relatively light material during high-energy sedimentary events, such as tsunami. In many ways, the stromatoporoid beds resemble modern accumulations oftsunami-derived boulders.

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Stromatoporoid growth orientation as a tool in palaeotopography : a case study from the Kadzielnia Quarry, Holy Cross Mountains, central Poland

Łuczyński P.

Acta Geologica Polonica

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2009

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Vol. 59, no. 3

319-340

EN

Growth orientation of stromatoporoids has allowed reconstruction of the palaeotopographic position of a large Frasnian organic buildup exposed in the Kadzielnia Quarry in the Holy Cross Mountains, central Poland. Two main, mature stage, stromatoporoid growth modes have been discerned: erect and semi-buried. The growth orientations of the stromatoporoids were studied in 17 sections that expose four different facies in the quarry. The inclinations of the basal surfaces of specimens and direction of the growth axes were measured and compared in terms of different growth modes, facies and positions in the organic buildup. The results support the earlier opinions that the inclined contact between the Kadzielnia stromatoporoid-coral limestones and the detrital limestones is depositional and represents an inclined depositional surface, and that the Kadzielnia buildup developed in a calm water setting below the storm wave base on a slope or at its foot. General conclusions emerging from the studies are: 1) stromatoporoid growth directions hold a key to reconstructing ancient topography; 2) erect stromatoporoids that grew on inclined surfaces changed the growth axes to the vertical direction during their growth; and 3) stromatoporoid growth directions and particularly the changing mode of growth of erect forms support the view that Palaeozoic stromatoporoids acted photosensitively.

10

Growth forms and distribution patterns of stromatoporoids exposed on Devonian palaeobottom surfaces; Holy Cross Mountains, central Poland

Łuczyński P.

Acta Geologica Polonica

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2008

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Vol. 58, no. 3

303-320

EN

Well preserved palaeobottom surfaces with stromatoporoids are exposed in two Devonian localities in the Holy Cross Mountains in central Poland: Skały and Bolechowice-Panek quarries. The stromatoporoids were subjected to morphometric analysis and distribution studies. Stromatoporoids were studied hitherto only in vertical cross sections; the study of three-dimensional stromatoporoid domes has created a need to introduce a new set of parameters describing their shapes, which includes: horizontal length and width, vertical height, elongation ratio and elongation azimuth. In order to make the measurements made by various methods comparable, and thus to allow comparable interpretations, recalculation formulas have been presented. Comparison of the results obtained by the two methods indicates that the measurements made in vertical cross sections substantially bias the dimensions and shapes of the stromatoporoids, which may influence stromatoporoid-based palaeoenvironmental reconstructions. The results of the measurements were interpreted in terms of palaeonvironmental conditions. In Bolechowice-Panek the stromatoporoids lived in a quiet shallow water setting with a low and stable sedimentation rate. In Skały the stromatoporoids grew in a shallow subtidal setting and located themselves on parallel ripples, most probably to escape being buried by deposits accumulating in inter-ripple depressions.

11

Stromatoporoid morphology in the Devonian of the Holy Cross Mountains, Poland, and its paleoenvironmental significance

Łuczyński P.

Acta Geologica Polonica

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2003

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Vol. 53, nr 1

19-27

EN

Stromatoporoid skeletons from polished slabs of stromatoporoid- and coral-bearing limestones of the Upper Devonian Kowala Formation from the Holy Cross Mountains in Central Poland have been measured using a classic parameterization method, introduced by KERSHAW & RIDING (1978) and improved by KERSHAW (1984, 1998). The stromatoporoid shape appeared to be strongly dependent on its size - the V/B ratio decreases along with increasing B. The relation can be well matched by a curve described by a formula: f(x) = 5.7103x^0.81633. The size of the measured specimens must therefore be taken into account in those studies of the stromatoporoid morphology, where it is concerned a palaeoenvironmental indicator. The stromatoporoids adopted several types of initial surfaces, corresponding to various growth strategies in the first phase of their growth in response to various environmental conditions, such as substrate consistency and sedimentation rate. Latilaminae arrangement well records the stromatoporoid growth history and therefore its studies are crucial in environmental interpretations, as the conclusions inferred from the shape alone might be very misleading.

12

Depositional evolution of the Middle Jurassic carbonate sediments in the High-Tatric succession, Tatra Mountains,Western Carpathians, Poland

Łuczyński P.

Acta Geologica Polonica

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2002

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Vol. 52, nr 3

365-378

EN

Facies development and tectonic history of the High-Tatric Middle Jurassic resembles that other regions of the Jurassic Tethys (e. g. Southern Alps, Spain). The Triassic carbonate platform disintegrated and divided into a system of horsts and grabens. Syndepositional extensional movements controlled the deposition. During the Aalenian carbonate-clastic sedimentation took place. During the Bajocian crinoidal meadows developed over most of the High-Tatric area. The Bathonian deposits belong to three main lithofacies: crinoidal, ferruginous and nodular limestones. The crinoidal limestones formed by deposition of pelmatozoan material transported over the sea-bottom in the form of megaripples. The ferruginous limestones developed in zones of restricted sedimentation, which were located above the areas of crinoid deposition that surrounded elevated blocks supplying terrigenous material. The nodular limestones represent deeper facies that were deposited on a slope descending towards a deep- sea basin. The Callovian wavy-bedded limestones mark the onset of pelagic deposition, which continued during the Late Jurassic.

13

Development history of Middle Jurassic neptunian dykes in the High-Tatric series, Tatra Mountains, Poland

Łuczyński P.

Acta Geologica Polonica

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2001

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Vol. 51, nr 3

237-252

EN

Neptunian dykes filled with Middle Jurassic sediments from the High-Tatric series in the Tatra Mountains are described. Six types of dykes, which constitute two groups, are distinguished, basing on the type of filling deposits, external shape of the systems and character of the walls. Group I embraces of the dykes with sharp-edged walls and predominantly vertical structures. Group II consists of dykes with smooth walls and predominantly horizontal structures. The distribution of particular types of dykes in the High-Tatric tectonic units is discussed. The processes of the initiation of dykes, their development and filling with deposits are reconstructed. The distribution of the dykes of Group I, their orientation, shape, size and relationship to the host-rocks, indicate the mechanical nature of the initiation phenomena. The dykes Group II underwent major reconstruction during the development stage, which made studies of their initiation impossible. Neptunian dykes belonging to Group I display features indicating the sole role of mechanical processes during their development. In the dykes of Group II chemical erosion played an important role. Different dykes were filled in different ways. Processes of injection of loose sediments into fissures opening in the solid substrate, rapid burying of open dykes by migrating dunes of crinoidal sand, and slow sieving of fine material into vast systems of voids, are proposed to explain in the filling of dykes by various types of sediments. The interpretation of the formation of internal breccias at the footwall of a fault scarp is presented. The influence of pressure dissolution phenomena on the post-depositional history of the neptunian dykes is evaluated. Field and microscopic observations were complemented by isotopic analyses of the sediments and calcite cements filling the dykes. Paleogeographic conclusions based on the characters of the neptunian dykes are given.

14

Morfologia stromatoporoidów jako wskaźnik paleośrodowiska

Łuczyński P.

Przegląd Geologiczny

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1998

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Vol. 46, nr 7

617-621

PL

Stromatoporoidy są ważnym elementem wielu paleozoicznych kompleksów węglanowych. Występują one w ciągłym wachlarzu kształtów obejmującym formy tabliczkowe, kopulowe, bulwiaste i krzaczaste. Pomimo nadal niepewnej pozycji systematycznej stromatoporoidów, ich cechy morfometryczne są uważane za dobre wskaźniki paleośrodowiska i co za tym idzie mogą być brane pod uwagę w rozważaniach paleoekologicznych. Obok samego kształtu są to układ latylamin oraz typ powierzchni. Wpływ czynników ekologicznych na cechy morfologiczne danego okazu jest tu większy niż w innych grupach bentosu osiadłego ze względu na stosunkowo niski poziom organizacji kolonii. Przedstawiona została metoda parametryzacji kształtów, stromatoporoidów (ryc. 1-3) zaproponowana przez Kershawa i Ridinga (1978) i udoskonalona przez Kershawa (1984). Głównymi elementami środowiska depozycji mającymi wpływ na kształt stromatoporoidów były: tempo depozycji, dynamika wód, prądy morskie i charakter podłoża.