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New data on the age of the sedimentary infill of the Orava-Nowy Targ Basin : a case study of the Bystry Stream succession (Middle/Upper Miocene, Western Carpathians)

Wysocka A., Łoziński M., Śmigielski M., Czarniecka U., Bojanowski M.

Geological Quarterly

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2018

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Vol. 62, No. 2

327--343

EN

The Neogene sedimentary succession of the Orava-Nowy Targ Basin directly overlies the Central Carpathian Paleogene Basin deposits, the Magura Unit, and the Pieniny Klippen Belt. It provides an excellent geological record that postdates the main Mesoalpine structural and geomorphological processes in the Western Carpathians. Sedimentological, petrographical and geochronological investigations have allowed forthe re-examination of pyroclastic material, zircon dating, and a discussion on the relation of the Orava-Nowy Targ Basin to the exhumation of the Tatra Massif. The Bystry Stream succession is composed of NNW-inclined freshwater siltstones, sandstones and conglomerates. A few small, sometimes discontinuous, light grey intercalations of pyroclastic deposits and a single 1-2 m thick tuffite layer occur in the upper part of the succession. The tuffite contains an admixture of organic matter and siliciclastic grains (e.g., mica), suggesting that the volcanic ash fall was accompanied by normal deposition from weak currents. Sedimentation of deposits of the Bystry Stream succession took place in terrestrial settings, predominantly on floodplains and in rivers, in the vicinity of a hilly area supplying the basin with eroded material. The age of the tuffite layer from the Bystry Stream succession was determined at 11.87 +0.12/-0.24 Ma. The source of volcanogenic material in the tuffite was probably volcanic activity in the Inner Carpathians-Pannonian region, where effusive and volcanoclastic sillca-rich rocks were being produced by extrusive and explosive activity ~12 Ma. Obtained result connects the development of the Orava-Nowy Targ Basin at ~12 Ma with the late stage of the main episode of the Tatra Massif exhumation between ~22-10 Ma.

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Lithofacies and terrestrial sedimentary environments in AMS measurements: case study from Neogene of Oravica River section, Čimhová, Slovakia.

Łoziński M., Ziółkowski P., Wysocka A.

Geological Quarterly

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2016

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Vol. 60, No. 2

259--272

EN

The anisotropy of magnetic susceptibility (AMS) of sedimentary rocks has been used for interpreting wide range of processes: early rock deformations, palaeotransport directions, as well as the evolution of mineral content. Various sedimentary factors which may determine magnetic susceptibility within lacustrine, river, floodplain and swamp deposits have been examined in the Oravica section of the Orava-Nowy Targ Basin. Multiple components of mineral content: illite, chlorite, smectite, kaolinite, quartz and unidentified high susceptibility phase make an AMS interpretation of this content ambiguous. However, this method may be useful for tracing early diagenetic geochemical/microbial processes where iron element is involved. Some sedimentary processes may be recognized from AMS when an assemblage of parameters is studied together: bulk susceptibility, the degree and the shape of anisotropy, principal directions, and the distribution of all these parameters within a set of specimens. Debris-flow processes, as well as lacustrine and floodplain sedimentation are especially well-defined in AMS results. Palaeotransport directions are ambiguous because studied rocks have undergone weak deformation what overprints this sedimentary feature. Most specimens represent an oblate shape of anisotropy and show a good correlation of minimum susceptibility axis and normal to bedding plane.

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Neogene terrestrial sedimentary environments of the Orava-Nowy Targ basin : case study of the Oravica section near Čimhová, Slovakia

Łoziński M., Wysocka A., Ludwiniak M.

Geological Quarterly

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2015

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Vol. 59, No. 1

21--34

EN

The Orava-Nowy Targ Basin is an intramontane depression located at the border of the Inner and Outer Carpathians. It is filled mostly with fine-grained terrestrial and fresh-water deposits of Neogene and Quaternary age, which record the structural evolution and denudation processes of the surrounding regions: Orava, Podhale, and the Tatra Mts. The Orava-Nowy Targ Basin fill was studied in the Oravica River section, which reveals 90 m thick Neogene deposits and allows observation of their lateral diversity. Fifteen lithofacies and seven facies associations distinguished here document the depositional evolution of the basin fill, starting from hill-slope debris flow through silt turbidite-bearing lake, to flood-dominated fluvial plain, swamp and alluvial fan deposits, as well as a pyroclastic event. The palaeorelief was low during deposition and the Orava-Nowy Targ Basin could have spread significantly more to the south.