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The intramontane Orava Basin - evidence of large-scale Miocene to Quaternary sinistral wrenching in the Alpine-Carpathian-Pannonian area

Ludwiniak Mirosław, Śmigielski Michał, Kowalczyk Sebastian, Łoziński Maciej, Czarniecka Urszula, Lewińska Lena

Acta Geologica Polonica

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2019

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Vol. 69, no. 3

339--386

EN

The Carpathian Orava Basin is a tectonic structure filled with Neogene and Quaternary deposits superimposed on the collision zone between the ALCAPA and European plates. Tectonic features of the south-eastern margin of the Orava Basin and the adjoining part of the fore-arc Central Carpathian Palaeogene Basin were studied. Field observations of mesoscopic structures, analyses of digital elevation models and geological maps, supplemented with electrical resistivity tomography surveys were performed. Particular attention was paid to joint network analysis. The NE-SW-trending Krowiarki and Hruštinka-Biela Orava sinistral fault zones were recognized as key tectonic features that influenced the Orava Basin development. They constitute the north-eastern part of a larger Mur-Mürz-Žilina fault system that separates the Western Carpathians from the Eastern Alps. The interaction of these sinistral fault zones with the older tectonic structures of the collision zone caused the initiation and further development of the Orava Basin as a strike-slip-related basin. The Krowiarki Fault Zone subdivides areas with a different deformation pattern within the sediments of the Central Carpathian Palaeogene Basin and was active at least from the time of cessation of its sedimentation in the early Miocene. Comparison of structural data with the recent tectonic stress field, earthquake focal mechanisms and GPS measurements allows us to conclude that the Krowiarki Fault Zone shows a stable general pattern of tectonic activity for more than the last 20 myr and is presently still active.

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Próba interpretacji litogenetycznej osadów diamiktonowych w Kotlinie Orawskiej (Karpaty Zachodnie)

Chmielowska D.

Landform Analysis

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2015

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Vol. 28

3--14

PL

Pokrywą fluwioglacjalnych żwirów w terasach i stożkach Czarnego Dunajca w Kotlinie Orawskiej są osady gliniaste o miąższości 1–3 m. Ich geneza, cechy teksturalne i strukturalne są dotychczas bardzo słabo poznane. Niniejszy artykuł jest analizą jednej z cech tych osadów – ich uziarnienia. Przebadano 25 próbek tych osadów, pobranych z odsłonięć i wierceń, stosując graficzne wskaźniki uziarnienia opracowane przez Folka i Warda (1957). Wyniki analiz osadów wskazują, że na większości stanowisk badawczych uziarnienie glin różni się w małym zakresie. W profilach pokrywy gliniastej występuje lokalnie tendencja wzrostu ku stropowi udziału frakcji grubo pyłowych, maleje natomiast udział w tym kierunku frakcji piaskowej lub też uziarnienie jest jednorodne w całym profilu. W wierzchowinowych strefach stożków plejstoceńskich gliny mają masywną strukturę, na niższych terasach Czarnego Dunajca zaznacza się niewyraźne warstwowanie. Cechy uziarnienia badanych osadów nie rozstrzygają jednoznacznie o ich genezie, osady te wydają się być poligeniczne.

EN

The topmost part of gravelly fans and glacifluvial terraces of the Czarny Dunajec in the Orava Basin consists of 1–3 m thick layer of diamictic deposits. Their origin and structural and textural characteristics have not been so far well-recognized. This paper focuses on one of these characteristics i.e. grain-size. Samples of diamictic sediments were collected at 25 sites (natural outcrops, trenches, bore holes) and studied using graphic measures by Folk and Ward (1957). The results of the analysis indicate that grain-size of the sampled material is very similar. Locally, vertical profiles of the loamy cover shows a tendency to the upward increase in the proportion of coarse-grained silt with the concurrent decrease of sand; or the grain-size is similar in the entire profile. The proportion of clay in the loams is relatively small. Analyzed diamictons are massive in the hilltop sections of the Pleistocene fans, while on the terraces of the Czarny Dunajec River weakly pronounced layering occurs. The origin of the studied deposits cannot be unambiguously determined on the basis of their grain-size characteristics; in turn, the origin of the loams seems polygenetic.

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Charakterystyka sedymentacyjna stropowych osadów stożka domańskiego (neogen/plejstocen) w Kotlinie Orawskiej

Kukulak J.

Studia Geologica Polonica

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1998

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Vol. 111

93-111

PL

Wierzchowinową część Domańskiego Wierchu na Orawie budują dwie serie osadów różniące się litologią. Należą one do dwóch różnowiekowych stożków napływowych o odmiennym pochodzeniu materiału. W jego niższej części (stożek osadów fliszowych) zalegają warstwy ilasto-mułowe na przemian z piaszczysto-żwirowymi, o miąższości 4-10 m i upadzie 10-30° ku NNW. Żwiry są dobrze obtoczonymi (0,59) okruchami piaskowców fliszowych, o dominujących frakcjach 32-64 i 65-128 mm, o kształcie dyskoidalnym i elipsoidalnym. Stropową część profilu (stożek z materiału tatrzańskiego) tworzą gliny o miąższości 0,5-1,5 m, z okruchami skał krystalicznych, zalegające niezgodnie na żwirach piaskowcowych. Osady w całym profilu są silnie zwietrzałe.

EN

The 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).