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EN
Sparry limestone, ferruginous muddy limestone and limestone breccia have been found in the Western Tatra Mts. They occur within Jurassic rocks of the Choč Nappe just below red conglomerates of probable Eocene age. The deposits found bear strong resemblance to the infill of subterranean karst forms. They differ significantly from Quaternary karst deposits of the Tatra Mts. The δ18O values of spelean carbonates suggest crystallisation at relatively high temperatures (over 20°C) whereas their relatively negative δ13C values imply the presence of soil-derived CO2 linked with vegetation dominated by C3 pathway plants. The karst forms and their infill were formed before the Eocene transgression, which shows unequivocally that the Tatra Mts. were subjected to karstification at that time.
EN
Latest Eocene plant macrofossils and trace fossils collected a century ago by Wiktor Kuźniar are revised and their stratigraphical and palaeoecological meaning is re-considered. They derive from marine limestones and marls cropping out on the northern slope of the Hruby Regiel mountain in the Western Tatra Mountains. Leaves belonging to the families Fagaceae and Lauraceae and fruits of the palm Nypa are recognized. The co-occurrence of the planktonic foraminifer taxa Chiloguembelina cf. gracillima and Globigerinatheca cf. index and fruits of Nypa suggests a latest Eocene age of the fossil flora. The plant assemblage is typical of paratropical or subtropical evergreen forests in a warm and humid subtropical climate, recent counterparts of which occur in southeast Asia. The presence of Nypa is characteristic of mangroves. The good state of preservation of the leaves suggests coastline proximity during sedimentation of the plant-bearing deposits.
EN
Minimally invasive surgery revolutionized operative procedures in the last 20 years. Much of the progress in minimally invasive surgery can be attributed to the development of robot-based systems. The most apparent changes are found in laparoscopy procedures. Procedures in which only small skin incisions are made have revolutionized operating theaters. The learning curve, although long in itself, allows for the development of procedures with reduced perioperative risk (i.e., bleeding, pain) or shorter postoperative period. Convalescence after endoscopy procedures is significantly shorter compared with classic laparotomy. However, certain limitations apply to laparoscopy. Apart from the long learning curve, movements executed with long and rigid tools cannot strictly translate the precision of an operator’s hand. The body position of the surgeon is often forced by the reach of the endoscope instrument. It is related to a significant physical load of personnel, especially during long operating procedures. For this reason, some therapeutic procedures are still executed using the laparotomy approach.
EN
Middle-Upper Jurassic pelagic carbonates and radiolarites were studied in the Krížna Nappe of the Tatra Mountains (Central Western Carpathians, southern Poland and northern Slovakia). A carbon isotope stra- tigraphy of these deposits was combined with biostratigraphy, based on radiolarians, calcareous dinoflagellates and calpionellids. In the High Tatra and Belianske Tatra Mountains, the Bajocian and part of the Bathonian are represented by a thick succession of spotted limestones and grey nodular limestones, while in the Western Tatra Mountains by relatively thin Bositra-crinoidal limestones. These deposits are referable to a deeper basin and a pelagic carbonate platform, respectively. The various carbonate facies are followed by deep-water biosiliceous facies, namely radiolarites and radiolarian-bearing limestones of Late Bathonian-early Late Kimmeridgian age. These facies pass into Upper Kimmeridgian-Lower Tithonian pelagic carbonates with abundant Saccocoma sp. The bulk-carbonate isotope composition of the carbonate-siliceous deposits shows positive and negative S C excursions and shifts in the Early Bajocian, Late Bajocian, Early Bathonian, Late Bathonian, Late Callovian, Middle Oxfordian and Late Kimmeridgian. Additionally, the S13C curves studied show a pronounced increasing trend in the Callovian and a steadily decreasing trend in the Oxfordian-Early Tithonian. These correlate with the trends known from the Tethyan region. The onset of Late Bathonian radiolarite sedimenlalion is marked by a decreasing trend in S13C. Increased S13C values in the Late Callovian, Middle Oxfordian and Late Kimmeridgian (Moluccana Zone) correspond with enhanced radiolarian production. A significant increase in CaCO3 content is recorded just above the Late Callovian S13C excursion, which coincides with a transition from green to variegated radiolarites.
EN
The article deals with the carbonates, filling fissures in limestone bedrock and presently exposed in a south-facing rock wall of Kramnica hill (Pieniny Klippen Belt, southern Poland). The carbonates are composed of (i) needle-fibre calcite crystals, (ii) carbonate nanofibres, (iii) carbonate nanoparticles, and (iv) micrite and sparite calcite crystals. Detrital grains from the carbonate bedrock occur subordinately. The spatial relationships of the components give documentation that the nanofibres were formed simultaneously with or slightly later than the needle-fibre calcite crystals. There exists a continuous chain of forms from nanoparticles to elongated nanofibres. This, in turn, indicates that all the above morphological forms are related genetically. In relatively wide fissures, the carbonates studied formed stepped microterracettes, similar to those of speleothems, mainly of moonmilk type. Conversely, narrow fissures are completely filled with carbonates, which display parallel lamination. The carbonates were formed in the late Holocene. However, “dead carbon effect” precludes the possibility of any precise dating of them. Their δ13C and δ18O values are in ranges from -5.1‰ to -3.8‰ and from -6‰ to -4.7‰, respectively. The carbonates studied bear a strong resemblance to soil and spelean, moonmilk-type carbonates. This indicates that continuity exists between the depositional environments of soil and spelean carbonate.
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.
EN
Nummulites-Discocyclina bioclastic packstone and Discocyclina rudstone occur in the transgressive sequence of the Middle–Upper Eocene deposits in the Tatra Mts. The succession of the studied facies is a direct response to a rapid environmental change, related to progressive deepening. Facies transition from Nummulites- Discocyclina bioclastic packstone of proximal mid-ramp to Discocylina rudstone of distal mid- and outer-ramp is an exemplary record of a deposition during deepening conditions. Increasing of diversity of the genus Discocyclina, decreasing of diversity of other foraminifera up the section and vertical variation of orthophragminid mor- photypes from the ovate- through saddle- to the disc-shaped tests are related to deepening and shadowing of the depositional environment.
EN
The Lower Jurassic Adnet type red limestones and marlstones (Kliny Limestone Member, Huciska Limestone Formation) of the Krížna unit in the Tatra Mountains comprise cephalopod fauna represented by ammonites, belemnites and rarely by nautiloids. Ammonites belong to the families Phyloceratidae, Lytoceratidae, Hildoceratidae and Dactylioceratidae and indicate Early Toarcian Serpentinum Zone, Middle Toarcian Bifrons Zone (most probably Sublevisoni and Bifrons Subzones) and Late Toarcian Pseudoradiosa Zone. Hence, the age of Adnet type deposits may be estimated as Early Toarcian-Late Toarcian. Relatively moderate diversity of ammonite assemblage is noticed. Ammonites and nautiloids are preserved mainly as internal moulds, only some specimens display preserved calcified shells. Part of this macrofauna has resedimented character. Studied ammonite assemblage is closely related to that of the Mediterranean Province.
EN
Bositra limestones of Aalenian–Lower Bathonian age crop out in the Krížna unit in the Western Tatra Mountains (Poland). They are sandwiched between pelagic red limestones and radiolarites and display lateral facies variation. Four facies were distinguished: (i) Bositra packstones/grainstones, (ii) crinoidal packstones/ grainstones, (iii) Bositra-crinoidal packstones, and (iv) Bositra-radiolarian wackestones. The Bositra packstones/ grainstones were laid down in high-energy setting, while Bositra-radiolarian wackestones in calm condition. Crinoidal packstones/grainstones represent density current deposits. Bositra-crinoidal packstones resulted from intense bioturbation and mixing of crinoidal packstones/grainstones with background Bositra-rich deposits. Topographic gradient affected the lateral facies variation. Taphonomic factors strongly controlled by energy of the sedimentary environment, ecological factors which caused domination of Bositra bivalves in benthos assemblage and dissolution eliminating non-calcitic bioclasts could resulted in formation of the Bositra limestones. The eutrophication of water column and remodelling of the Krížna Basin, which finally led to deposition of radiolarites seem to be of considerable importance. Hence, Bositra limestones can be regarded as the record of the interme- diate stage of the basin evolution towards radiolarite formation.
PL
Wapienie bositrowe wczesnego aalenu–wczesnego batonu, które odsłaniają się w jednostce kriżniańskiej w Polskich Tatrach Zachodnich znajdują się w profilach pomiędzy pelagicznymi czerwonymi wapieniami a radiolarytami (Fig. 1, 2; Lefeld et al., 1985; Gradziński et al., 2004). Wapienie te wykazują wyraźne facjalne zróżnicowanie. Wydzielone zostały następujące facje: (i) bositrowe pakstony/greinstony, (ii) krynoidowe pakstony/greinstony, (iii) bositrowo-krynoidowe pakstony i (iv) bositrowo-ra diolariowe wakstony (Fig. 2, 3). Bositrowe pakstony/greinstony powstały w środowisku o stosunkowo wysokiej energii, a bositrowo- radiolariowe wakstony w warunkach niskiej energii. Krynoidowe pakstony/greinstony są interpretowane jako osady prądów gęstościowych, a bositrowo-krynoidowe pakstony jako osady prądów gęstościowych zbioturbowane i zmiksowane z osadami tła depozycyjnego. Zróżnicowana morfologia basenu wpłynęła na oboczną zmienność facjalną omawianych wapieni i przestrzenny rozkład facji (Fig. 4). Powstanie wapieni bositrowych było warunkowane przez czynniki natury tafonomicznej, związane z energią środowiska sedymentacji, natury ekologicznej decydujące o dominacji bositr w zespole bentosu i procesy rozpuszczania eliminujące nie kalcytowe bioklasty. Postępująca eutrofizacja wód (Bartolini & Cecca, 1999; Cobianchi & Picotti, 2001) i przemodelowanie basenu kriżniańskiego związane z procesami ryftingu Zachodniej Tetydy, które ostatecznie doprowadziły do depozycji radiolarytów, wydają się mieć zasadniczy wpływ na powstanie wapieni bositrowych. Tak więc, wapienie bositrowe reprezentują przejściową fację poprzedzającą w czasie powstanie tetydzkich jurajskich radiolarytów.
EN
Lower-Middle Jurassic glaucony-bearing deposits crop out in the Polish part of the Križna Unit in the Western Tatra Mts. These deposits, up to 20 cm thick, consist of glaucony-rich marls and limestones. The glaucony grains constitute up to 30% volume of the deposits. They represent an evolved stage of glauconitization since they contain more than 7% K2O. The content of Al2O3 is high (up to 19.97%, average 16.98%) while the content of Fe2O3 is low (not more than 23.48%, average 12.84%). These features are interpreted as a product of diagenetic processes. The glaucony-bearing deposits were formed at an upper bathyal depth and their rate of deposition was very low, what allowed long-lasting evolution of the glaucony grains. The K-Ar age of the glaucony grains is much younger than the biostratigraphic age of the studied section. The lowering of the K-Ar dates is interpreted as a result of loss of radiogenic Ar from the lattice of the glaucony.
EN
Lower Jurassic spiculite series was studied in the Polish part of the Križna Unit in the Western Tatra Mts. This series consists of interbedded spiculites and crinoidal limestones. The spiculites are built almost entirely of siliceous sponge spicules belonging to Hexactinellida and Demospongiae classes. The prolific growth of siliceous sponge community was caused by favourable topographic and bathymetric conditions and by increased content of dissolved silica in the seawater. The spicules were not transported. Crinoidal limestones intercalating with spiculites are composed predominantly of crinoidal ossicles redeposited from shallower parts of the basin by gravity currents generated by storm events. The deposits of the studied series reveal a shallowing upward trend, marked by upward gradual replacement of hexactinellids by demosponges and by thickening and coarsening of the crinoidal limestone layers.
12
Content available remote Jaskinie lawowe - zarys problematyki
PL
Jaskinie rozwinięte w lawach są stosunkowo słabo znane pomimo tego, że są one częstym zjawiskiem w wielu rejonach świata. Większość takich jaskiń to fragmenty tzw. rur lawowych. Powstanie rur lawowych jest związane ze spływami lawy bazaltowej. Najczęściej rury takie są rozwinięte w lawach pahoehoe cechujących się małą lepkością, lecz znane są także z law aa o większej lepkości. Powstanie rur lawowych jest wynikiem różnych procesów. Najczęściej jest efektem rozwoju skorupy ponad płynącym strumieniem lawy. Taka skorupa ostatecznie pokrywa cały potok lawowy. Powstaje ona dzięki gradientowi termicznemu pomiędzy płynącą lawą a atmosferą. Rury lawowe są dobrymi izolatorami cieplnymi i pełnią rolę kanałów dla strumieni lawowych płynących na duże dystanse. Dlatego też powstanie rur lawowych jest bardzo istotnym czynnikiem dla rozwoju rozległych spływów lawowych. Płynąca lawa powiększa rurę lawową na skutek erozji termicznej i mechanicznej. Dzięki temu wewnątrz rur lawowych powstają wcięte meandrujące koryta, lawospady, świetliki i toczeńce lawowe. Inne charakterystyczne elementy rur lawowych jak półki znaczące dawny poziom potoku lawowego, wały przykorytowe, wewnętrzne rury są efektem akrecji lawy wewnątrz rur lawowych. W jaskiniach lawowych występują też różnorodne speleotemy zbudowane z gipsu, węglanu wapnia i opalu.
EN
Caves developed in lavas are not broadly known despite the fact that they are quite a common phenomenon in some parts of the world. Majority of such caves form as lava tubes and they are called lava tube caves. The origin of lava tubes is related to flows of basaltic lava. They are mostly developed in a low-viscous pahoehoe type of basaltic lava, but some caves located in a viscous aa lava are also known. The origin of the lava tubes has been ascribed to various mechanisms. The most frequent seems to be the growth of stationary crust over a flowing lava stream. Finally, this crust completely roofs a lava stream. This is brought about by a contrasting thermal gradient between the flowing lava and the atmosphere. The lava tubes are good heat isolators and they act as long conduits for flowing lava. Thus, they are a very important factor for propagation of lava and the origin of broad lava flows. The flowing lava widens the tube as a result of thermal and mechanical erosion. The above processes form several characteristic features of lava tube interior, e.g. incised meandering channels, lavafalls, skylights, lava balls. Other features, for example, lateral benches, internal levees, tube-in-tube structures, are effects of lava accretion inside the tubes. Various speleothems made of gypsum, calcium carbonate, as well as opal can form in lava tube caves.
EN
New locality of slope breccias was found in the Western Tatra Mts. It occures in the Długa Valley on a steep slope of ravine beneath the belt of Jurassic radiolarite cliffs. The brecccia consists of angular clasts of radiolarite bound with calcite cements. Void spaces between the clasts contain shells of Holocene snails. The cements are built of columnar crystals composed of acicular subcrystals and of skeletal crystals. The crystals grew rapidly from supersaturated solution due to CO2 degassing. Cementation occurred in vadose conditions in the Atlantcic Phase soon after the scree formation.
15
PL
Obszar Alwernia-Brodla-Grojec nie był do tej pory szczegółowo kartowany, w wyniku czego ważne elementy tektoniczne nie były wyznaczone na publikowanych mapach geologicznych. Linie uskoków wyznaczono na podstawie kartowania oraz wykorzystano dostępne materiały wiertnicze. Obecnie wyróżniono tu dwie generacje uskoków: starszą od paleogeńskiej powierzchni zrównania, która nie zaznacza się w morfologii terenu, oraz młodszą, której uskoki wyznaczają widoczne w morfologii zręby i rowy tektoniczne. Stwierdzono istnienie uskoku w Brodłach, gdzie w skarpie znajduje się ostatnie na zachód odsłonięcie wapieni jurajskich w rowie Rybnej.
EN
Until now, Alwernia-Brodla-Grojec area has not been mapped in detail and its tectonic features has not been indicated on published geological maps. The aim of the article is to fill up the vacant part. The tectonics of this part of the Cracow Upland is dominated by Tertiary block-faulting. This faulting includes: 1 - the lower Tertiary faults produced before the onset of Paleogene planation and, 2 - the Neogene faults. These latter are clearly expressed in the present topography in the form of gravity elevated horsts flanked by step-fault escarpments. It is to be noted that the fault scarp in Brodla is the last exposure of Jurassic limestones in the Rybna graben.
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