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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.

3

Young tectonics of the Orava Basin and southern portion of the Magura Nappe, Polish western Carpathians, in the light of gravity studies: a new research proposal

Łój M., Madej J., Porzucek S., Zuchiewicz W.

Studia Quaternaria

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2007

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Vol. 24

53-60

EN

The aim of this paper is to present a multidisciplinary project dealing with analysis of young crustal movements in the Orava Basin, Polish Western Carpathians, on the basis of a three year long gravimetric, geodetic, geological and morphostructural study. The problem consists in quantitative interpretation of the obtained gravimetric results, i.e. in combining temporal gravity changes with those of geodynamic crustal processes. Gravity surveys conducted in 2004 and 2005 show a decrease in gravity values at benchmarks situated in the Central Carpathian Palaeogene Basin and Magura Nappe, while the central potion of the Orava Basin reveals the opposite trend. Such changes, if confirmed by successive measurement campaigns, appear to indicate recent uplift of the basin margins and subsidence of the basin itself.