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Studia Geologica Polonica vol. 111 (Abstracts) Studia Geologica Polonica, 111: 7-92. Planktonic foraminiferal biostratigraphy, Upper Cretaceous red pelagic deposits, Pieniny Klippen Belt, Carpathians Krzysztof BĄK Institute of Geography, Cracow Pedagogical University, ul. Podchorążych 2, 30-084, Kraków, Poland; sgbak@cyf‑kr.edu.plAbstract
SGP Home Page Volume content Studia Geologica Polonica, 111: 93-111. Charakterystyka sedymentacyjna stropowych osadów stożka Domańskiego Wierchu (neogen/plejstocen) w Kotlinie Orawskiej Józef KUKULAK Institute of Geography, Cracow Pedagogical University, ul. Podchorążych 2, 30-084, Kraków, Poland; jkukulak@ap.krakow.plStreszczenie
Sedimentary characteristics of the topmost deposits, Domański Wierch alluvial cone (Neogene/Pleistocene), Orawa Depression, Polish Carpathians SummaryThe Domański Wierch hill near Czarny Dunajec is a fragment of a Neogene alluvial fan (Fig. 1). It is built of gravels and sands alternating with clays and muds (Fig. 2). The material in the cone comes mainly from the Podhale Flysch. A thin cover of glacifluvial Pleistocene sediments derived from the Tatra Mountains overlies the Neogene fan sediments. Until recently, the sediments in the lower and middle parts of the hill were better studied. A new trench on the hill crest exposed the structure of sediments in the highest part of the hill (fig. 3). The sequence exposed in this trench includes, in its lower part, two layers of clays (A, C) separated by a series of gravels and sands (B) 9-10 m thick, all inclined to NW, and covered discordantly by a Mindelian glacifluvial cover (D) - Fig. 4. The sandy-gravelly series (B) contains accumulations of coarse and fine gravels, with 32-64 mm and 64-128 mm size fractions prevailing (Fig. 6). Sandstone pebbles are mostly discoidal and ellipsoidal (73% in total; Fig 7). Their mean roundness is 0.59, and those in the 64-128 mm size grade are the best rounded (Fig. 8). The azimuths of dipping of the surfaces of their greatest cross-section are concentrated in the interval 320-40° (Fig. 9). The inferred paleotransport direction is from the south, with due account for the lack of distinct imbrication and the postdepositional tectonic tilt.This inference is supported by a NE-NW - oriented cross-lamination in sand lenses and layers within the cone. The cover of the glacifluvial sediments (D) is strongly weathered, clayey. Only pebbles of quartzitic sandstones, the most resistant to weathering, are preserved. They form now a continuous horizon at the base of the cover. Most other pebbles were decomposed to clay. The base of the cover includes also faintly laminated clayey-muddy loams with clay balls. Similar loams fill frost wedges in the contact zone with the Neogene gravels (Fig. 10). SGP Home Page Volume content Studia Geologica Polonica, 111: 113-136. Budowa geologiczna jednostek reglowych Tatr Zachodnich Maria BAC-MOSZASZWILI Institute of Geological Sciences, Polish Academy of Sciences, ul. Twarda 51/55, 00-818 Warszawa, PolandStreszczenie
Geology of the Subtatric Units, Western Tatra Mts SummaryThe Subtatric zone makes up a longitudinal belt along northern edge of the High Tatra Mts (Fig. 1). It is represented by the Križna nad the Choč nappes of the Inner Carpathians. The western subtatric zone. West of the Kościeliska Valley, the Bobrowiec unit makes up the main subtatric mass (Fig. 2). It consists of monoclinal Triassic, Jurassic and Lower Cretaceous units in the typical Križna nappe development. Its Middle Triassic competent dolostones are split into smaller blocks. Amplitude of fault displacement between these block dimnishes upward. The entire zone is cut by a large Siodło dislocation in its central part. Enrichment in iron and manganese ores (Krajewski & Myszka, 1958), is associated wit the dislocation (Fig. 7). The tectonic sole of the Bobrowiec unit is thrust onto the Hightatric zone along a shear plane (Fig. 6). The Bobrowiec unit is overlain by a higher nappe showing lithostratigraphic characteristics of the Choč nappe (Nemčok et al., 1996). In the western part of the Tatra Mts, it consists of Triassic formations, but in the Kościeliska Valley - of Lower Jurassic ones (Fig. 3). The whole nappe structure had been peneplenised during early Paleogene, being then covered with clastic sediments of Middle Eocene age (Fig. 4). At the Siodło dislocation, and the one that terminates the western Subtaric zone in the east (between the Kościeliska and Mała Łąka Valleys), changes occur in the composition and thickness of the basal Eocene beds (Bac, 1971). The Zakopane Subtatric zone. The Zakopane Subtatric zone makes up a complicated tectonic structure consisting of several nappe units composed of Triassic and Lower Jurassic formations in the Križna nappe development (Fig. 8). The zone consists of two belts of Middle Triassic dolostones with the so-called Czerwona Przełęcz syncline inbetween. The latter is built of Upper Triassic and Lower Jurassic shaly beds. Knowledge of the Subtatric Triassic lithostratigraphy (Kotański, 1963) allowed to state that this part of the Subtatric zone is composed of isoclinal slice elements usually in tectonically normal position (Guzik & Kotański, 1963). Tectonic model of the western Subtatric zone in the Western Tatra Mts. The set of tectonic scales in the Zakopane Subtatric zone makes a form of duplexes in the sense of contraction tectonics (see Boyer & Elliott, 1982; Mitra, 1986). It is proved by isoclinal, normal position of the majority of the scales, with shearing planes cutting horizons of incompetent Lower Triassic and Keuper shales, with passing of overthrust planes into shearing planes. The cross-sections (Fig. 10) are limited to structural elements visible in the field. They show a distinct imbrication of tectonic units in the Zakopane Subtatric zone. One must, however, subtract the effect of postorogenic tectonic processes and, first of all, of a rotational post-nappe tilt of the Tatra massif which caused the nothward dip of the Mesozoic Subtatric sequence that primarily was nearly flat or only slightly tilted toward the south (Bac-Moszaszwili et al., 1982). Within the Zakopane Subtatric zone, the duplexing process had embraced the sequence from the Triassic to the Lower Jurassic. Younger formations are unknown from that zone. Such a process did not take place in the Western Tatra Mts where the Lower Subtatric nappe include sedimentary formations from Middle Triassic through the Lower Cretaceous inclusively. The two above mentioned Subtatric zones namely the Zakopane and the western one, contact with each other in a tectonically complicated area of Upłaz Miętusi. It was argued (Bac, 1971) that there is no superposition of these two zones as supposed earlier by Rabowski (1954) and Kotański (1965). The tectonic structure of Upłaz Miętusi is best explained by an en bloc thrust of the western Subtatric zone onto the Zakopane one (Figs 2-5, 8, 9). The basal Eocene beds also take part in this thrust (Bac-Moszaszwili et al., 1979), and reverse folds so common in the Bobrowiec unit (Bac, 1971; Piotrowski, 1987) are associated with it. Displacement of an upper part of the Bobrowiec unit, recognized in the Chochołowska Valley, also shows a reverse character (Figs 2, 5). Folds in the Zakopane subtatric zone are of similar character (Fig. 11). The Subtatric units of the Zakopane zone are cut in several places by transverse, rather broad dislocations (Figs 8, 9), of fault overthrust character. As follows from studies by Iwanow (1965), and Bac-Moszaszwili & Rudnicki (1979), the above mentioned thrust zones are tilted toward NW, similarly as it is the case with the thrust of the western subtatric zone over the Zakopane one. They separate units differing in structure (Fig. 9) and are accompanied by small retrofolds usually of drag fold type (Fig. 11). The amplitudes of displacements vary in particular units. They are largest in the lowermost Suchy Wierch unit and smallest within the basal Eocene. This suggests a gradual development of this zone that started already during the nappe process, and was subsequently rejuvenated. The development of reverse structures, and transformation of the transverse dislocation zones into flat overthrusts dipping from NW toward SE, may have been caused by the formation of the Parnica Sigmoide at the western termination of the Tatra Mts (Bac-Moszaszwili, 1993) as well as by other tectonic phenomena that took place at the Inner/Outer Carpathian boundary. The last post-Paleogene stage of displacements along the mentioned transverse dislocations, shown in fig. 12, was a clockwise rotation of the Subtatric blocks. This may be one of effects of transpression and block displacements at the Inner/Outer Carpathian boundary. This direction agrees well with results of palaeomagnetic (Grabowski, 1995) and geotectonic studies (Birkenmajer, 1985). The morphological observations done by the authoress (1995) in the Subtatric units led to acceptation of such direction of recent rotation along the north-Tatra lineament. SGP Home Page Volume content Studia Geologica Polonica, 111: 137-154. Ewolucja metamorficzna skał rejonu Błyszcza (Masyw Bystrej, Tatry Zachodnie) Robert PIWKOWSKI & Aleksandra GAWĘDA Department of Earth Sciences, Silesian University, ul. Będzińska 60, 41-200 Sosnowiec, Poland; gaweda@us.edu.plStreszczenie
Metamorphic evolution of crystalline rocks from Błyszcz Mt (Bystra Massif, Western Tatra Mts) SummaryIn the Western Tatra Mts, the Błyszcz-Bystra Massif is the highest point in the Main Ridge of the Upper Kościeliska Valley. This massif is built of metamorphic rocks intercalated by subordinate concordant granitic veins. In the Błyszcz area, six petrographical varieties of metamorphic rocks could be distinguished: amphibole-biotite gneisses, plagioclase-biotite gneisses, plagioclase-muscovite gneisses, two-mica gneisses, leucogneisses and migmatites. On the basis of mineral parageneses and geochemistry of the mineral constituents, as well as the geochemical characteristcs of whole-rocks samples, one could establish the pressure-temperature changes (P-T path) during the Błyszcz area evolution. The first stage, documented in the investigated rocks, was delimited as: 4-5 kbar of pressure and 710-730°C. The presence of staurolite relics indicates the lower temperature range, within the stability field of that mineral, but that older stage in highly obliterated. The almost isothermal decompression, induced by granitic veins intrusion and wild migmatite formation, shifted the stability field to about 2 kbar of pressure at the temperature of 700°C (second stage). The retrogressive changes (third stage) occured according to mineral reaction: Tsch + Pl + H2O ↔ Ep + Chl + Q, what is a typical paragenesis of the greenschist facies condition. The chemical analyses showed that most of the metamorphic rocks under consideration were metapelite-metapsammite in origin. The only exception is amphibole-biotite gneiss, having the geochemical features of metamorphosed andesite. The structural analyses showed some differences in foliation and main structural axis arrangements in Błyszcz Massif, when compared with the surrounding areas. Moreover, the individuality of the massif is expressed by its tectonic borders on E and W and P-T path different (T-dominated) from the other areas of Upper Kościeliska Valley. SGP Home Page Volume content Studia Geologica Polonica, 111: 155-179. Tektonika wzgórza zamkowego w Niedzicy, pieniński pas skałkowy Krzysztof BIRKENMAJER Institute of Geological Sciences, Polish Academy of Sciences, Cracow Branch, ul. Senacka 1, 31-002 Kraków, Poland; ndbirken@cyf‑kr.edu.plStreszczenie
Mapa
geologiczna szczytu wzgórza Zamku Niedzickiego [ plik PDF ]
Tectonics of the Niedzica Castle hill, Pieniny Klippen Belt, Polish Carpathians SummaryThree Upper Cretaceous tectonic units built of Lower Jurassic through Upper Cretaceous marine strata (see Birkenmajer, 1963a, 1977, 1986a): the Czorsztyn Unit, the Niedzica Nappe (tectonic scales), and the Branisko Nappe (tectonic scale), and a tectonic scale built of post-nappe conglomerate and flysch (Jarmuta Fm., Maastrichtian), crop out in the tectonic window of the Niedzica Castle hill, in the Pieniny Klippen Belt, Polish Carpathians (Figs 1-15, Pls I, II). The tectonic window of the Niedzica Castle hill is a very complex structure. It had formed as a result of four deformation phases (Birkenmajer, 1986a, 1988): (1) The Branisko and Niedzica nappes were thrust from the south over the Czorsztyn Unit (“autochthone”) during the Late Cretaceous folding (late Subhercynian = Ressenian, and early Laramian phases); (2) The Czorsztyn Unit, together with its overburden - the Branisko and Niedzica nappes, was thrust from the south over the post-nappe Jarmuta Formation (molasse and flysch: Maastrichtian) during the late Laramian folding (Maastrichtian/Paleocene boundary); (3) The Early Miocene, S-N-directed compression of the Savian phase had severely affected the Late Cretaceous/Early Palaeogene nappes and thrust-sheet (1, 2), which became transformed into vertically-stacked tectonic plaques and scales. Main structural features of the Niedzica Castle tectonic window were set out during this phase. The structure was further modified by longitudinal strike-slip faulting related to transpression at strike-slip northern and southern boundary faults of the Pieniny Klippen Belt (Birkenmajer, 1985, 1986a). Horizontal lateral displacements along competent/incompetent rock contacts in vertically-stacked pre-Savian tectonic units, had caused thinning and wedging-out of particular lithosomes, their brecciation and boudinage. As a result, massive competent limestones were very often detached as tectonic klippes from incompetent, plastically deformed, shales and flysch deposits, as is well visible in the Niedzica Castle tectonic window (see Fig. 14, Pls I, II); (4) The Middle Miocene, S-N-directed compression of the Styrian phase, caused further brecciation, and local folding. A younger system of strike-slip faults had developed in the Pieniny Klippen Belt. It often forms a pair of faults oriented NW-SE and NE-SW, respectively (Birkenmajer, 1985). Faults and joints of this system are well recognizable in competent limestones (crinoid limestone of the Smolegowa Fm., Bajocian; massive and crinoid limestones of the Dursztyn Limestone Fm., Tithonian-Berriasian) of the Czorsztyn Unit in the Niedzica Castle tectonic window (Fig. 11, Pl. I). The paper presents a detailed geological map, 1:100 scale, of the top part of the Niedzica Castle hill (Pl. I), several panoramic geological sketches of the castle foundations (Figs 11-13), and a detailed panoramic geological profile of the SE slope of the castle hill (Pl. II). They are based on natural and artificial exposures surveyed by the present author since the fifties, during the project (1953-1985) and the construction phases of the Czorsztyn water dam which was completed in 1997. Geological map of the Niedzica Castle Hill summit [ PDF file ] SGP Home Page Volume content |