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Geological setting and lithological inventory of the Czarna Woda conglomerates (Magura Nappe, Polish Outer Carpathians)

Oszczypko Nestor, Oszczypko-Clowes Marta, Olszewska Barbara

Acta Geologica Polonica

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2020

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Vol. 70, no. 3

397--418

EN

During the late Oligocene to early Miocene the residual Magura Basin was located along the front of the Pieniny Klippen Belt (PKB). This basin was supplied with clastic material derived from a south-eastern direction. In the Małe (Little) Pieniny Mts. in Poland, the late Oligocene/early Miocene Kremna Fm. of the Magura Nappe (Krynica subunit) occurs both in front of the PKB as well as in the tectonic windows within the PKB. Lenses of exotic conglomerates in the Kremna Fm. contain frequent clasts of Mesozoic limestones (e.g. limestones with “filaments” microfacies and Urgonian limestones) and Eocene shallow-water limestones. Fragments of crystalline and volcanic rocks occur subordinately. The provenance of these exotic rocks could be probably connected with Eocene exhumation and erosion of the SE part of the Dacia and Tisza Mega-Units.

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Chromian spinels from the Magura Unit (Western Carpathians, Eastern Slovakia) : their petrogenetic and palaeogeographic implications

Bónová K., Špisiak J., Bóna J., Kováčik M.

Geological Quarterly

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2017

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Vol. 61, No. 1

3--18

EN

Detrital chromian spinels in sedimentary rocks provide much information concerning the tectonics of their parental ultrabasic rocks. Chromian spinels occurring in the Eocene to Oligocene depos its from the Magura Nappe were exam i ned to provide some constraints on the history of the Magura Basin. The Magura Nappe is a part of the Flysch Belt belonging to the External Western Carpathians. The Magura Nappe is separated by a narrow zone associated with the Pieniny Klippen Belt and is divided into three principal tectono-lithofacies units (from the S to N): the Krynica, Bystrica and Rača units. Cr-spinel is a common accessory mineral (2.3-5.9 vol% of heavy mineral spectra) in the siliciclastic rocks of the Rača and Krynica units. In terms of texture and chemical composition, two types of Cr-spinels were recognized: unaltered and altered. Unaltered spinels were found to contain silicate inclusions such as chromio-pargasite, enstatite, diopside, pargasite, plagioclase and olivine (forsterite). The chromian spinels show wide variations in compositional parameters such as Cr# (0.3-0.7), Mg# (0.3-0.7), TiO2 (<0.03-1.9 wt.%) and Fe2+/Fe3+ (2.5-13) whereas the differences between the Rača and Krynica units are in- significant. These parameters suggest a peridotitic and volcanic origin of the spinels, respectively. The ophiolite source consisting of harzburgitic mantle peridotites was developed mainly in a supra-subduction zone setting; volcanic spinels indicate an origin in mid-ocean ridge basalts, back-arc basin basalts and sporadically in ocean-island basalts. Concerning their geochem i cal features, we propose that during the Eocene to Early Oligocene, the ophiolitic detritus in the eastern part of the Magura Basin deposits may have been derived from a source area located in the Fore-Marmarosh Suture Zone (Eastern Carpathians) that is considered an equivalent of the Black Flysch and Ceahlau units. Some Cr-spinels found in the Eocene sedimentary successions may have resedimented from older Late Cretaceous-Paleocene formations of the Magura Unit, which are considered as reworked sedimentary material from the Pieniny Klippen Belt.

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Early to Late Bajocian age of the "black flysch" (Szlachtowa Fm.) deposits: implications for the history and geological structure of the Pieniny Klippen Belt, Carpathians

Barski M., Matyja B. A., Segit T., Wierzbowski A.

Geological Quarterly

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2012

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Vol. 56, No 3

391-410

EN

The "black flysch" deposits (Szlachtowa Formation at Podubocze near Czorsztyn in Poland), attributed so far to the Pieniny Klippen Basin successions, and at Hałuszowa in Poland as well as at Kamienka in Eastern Slovakia, attributed to the Grajcarek Succession of the Magura Basin, have yielded rich dinoflagellate cyst assemblages consisting of forms both redeposited (from Upper Triassic to Aalenian) and indigenous (Lower Bajocian to Upper Bajocian). An Early to Late Bajocian age of the deposits investigated is thus indicated, and this along with other stratigraphical, sedimentological and tectonic data indicates that all the deposits in question represent the early stages of development of the Magura Basin. The formation of “black flysch” deposits was possibly related to the Early Bajocian uplift of the Czorsztyn Ridge which resulted from the opening of the Magura Ocean. The occurrence of the deposits of the Magura Basin below the overthrusted deposits of the Klippen Basin (Czorsztyn Unit) in the area of study results in a marked change in the structural interpretation of the Pieniny Klippen Belt.

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Architektura depozycyjna warstw magurskich w strefie Siar na południe od Gorlic (płaszczowina magurska, polskie Karpaty zewnętrzne)

Warchoł M.

Przegląd Geologiczny

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2007

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Vol. 55, nr 7

601-610

EN

Detailedanalysis of lithofacies and their distribution in the Magura Beds in 11 transects in the eastern part of the Siary zone, revealed 16 facies and 6 associations of genetically and spatially related facies. The facies spectrum evidences deposition from a variety of mass gravity processes and subordinately by hemipelagic rain. The facies associations reveal depositional patterns of submarine fans and include: channels, channel-levees, channel-lobe transitions, depositional lobes and slump bodies. Correlation results (9 sections) and facies distribution together with paleocurrent directions suggest that the deposition of this part of Magura Beds took place in a submarine ramp/apron hybrid setting fed from a multipoint source. The depositional pattern of the Magura Beds in the study area records a two-stage development, which began with the emplacement of a sand/mud-rich type system and was followed by a mud-dominated system.

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Egzotyki strefy krynickiej (płaszczowina magurska) i ich znaczenie paleogeograficzne

Oszczypko N., Oszczypko-Clowes M., Salata D.

Geologia / Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie

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2006

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T. 32, z. 1

21-45

PL

Poziomy egzotykowe w strefie krynickiej grupują się w utworach formacji szczawnickiej, zarzeckiej i magurskiej. Wśród egzotyków skał osadowych strefy krynickiej rozpoznano: pelagiczne wapienie tytonu-neokomu oraz litotamniowe wapienie paleogenu. W egzotykach magmowych większość to wulkanity, natomiast skały metamorficzne to głównie łupki łyszczykowe i gnejsy. Egzotyki skał osadowych i krystalicznych strefy krynickiej różnią się od tych z formacji jarmuckiej (mastrycht--paleocen) jednostki Grajcarka. Egzotyki eocenu i oligocenu strefy krynickiej nie wykazują bezpośredniego związku z pienińskim pasem skałkowym, a skały krystaliczne pochodzą z erozji terranu kontynentalnego. Pochodzenie egzotyków może być związane z eoceńską ekshumacją podłoża basenu magurskiego lub z domeną wewnętrznokarpacką (wewnętrzne Dacydy i/lub terran Cisy (Tisza))

EN

Sedimentary beds containing exotic pebbles occur in the Krynica Subunit. They occur mainly in deposits of the Szczawnica, Zarzecze and Magura fms. Pelagic limestones (Tithonian- -Neocomian) and lithothamnium limestones (Palaeogene) were recognized among sedimentary rocks of the Krynica Zone. Volcanites, rarely granitoides as well as schists, gneisses, quartzites and cataclasites were found in the group of crystalline exotic pebbles. The exotic pebbles from the Eocene--Oligocene beds of the Krynica Zone differ from those found in the Jarmuta Fm (Maastrichtian--Palaeocene) of the Grajcarek Unit. The exotic pebbles of the Krynica Subunit do not have direct connection with the Pieniny Klippen Belt, whereas crystalline rocks derived from a continental terrain. The provenance of these rocks could be connected with Eocene exhumation of the Magura Basin basement or with the Inner Carpathian realm (Inner Dacides and/or Tisza terrain)

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Provenance analyses of the Late Cretaceous-Palaeocene deposits of the Magura Basin (Polish Western Carpathians) : evidence from a study of the heavy minerals

Oszczypko N., Salata D.

Acta Geologica Polonica

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2005

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Vol. 55, no. 3

237-267

EN

The Late Cretaceous-Palaeocene sequence of the Magura Nappe in Poland is underlain by the Albian-Cenomanian spotty marls at the base and overlapped by the Palaeocene/Early Eocene variegated shales at the top. The spotty marls are followed by variegated shales and then by turbiditic deposits. The upper boundary of the variegated shales is diachronous - older in the Raca zone (Santonian) and younger in the Krynica zone (Campanian/Maastrichtian). The turbiditic deposits of the marginal (northern) zone of the Magura Nappe display palaeocurrent directions from the NW in the western part and from the NE in the eastern part. In other parts of this unit palaeocurrent directions from the SE and E were observed. The northern source area of the Magura Basin is commonly connected with the Silesian Ridge, while the south-eastern one could be connected with an accreted fragment of the Inner Carpathians.The heavy mineral assemblages of the Magura Nappe are dominated by stable and ultrastable species. Chromian spinels occur additionally in the Krynica zone and to some extent in the Bystrica and Raca zones. Investigation of the chemical composition of the heavy minerals showed that that the southern source area was built of low- to medium-grade metamorphic rocks, as well as igneous rocks associated with ophiolite sequences. The chemical composition of minerals deriving from the NW indicates that they crystallized mainly in low- to high-grade metamorphic rocks and granitoids.