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The Upper Cretaceous variegated shales in the Ropianka Formation of the Magura Nappe (Outer Carpathians) : age and lithostratigraphic position

Waśkowska Anna, Szczęch Mateusz

Geological Quarterly

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2023

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Vol. 67, No. 2

art. no. 18

EN

The lithological characteristics and age analysis of the variegated Farony Shale are presented for the first time. The Farony Shale occurs in the Lubomierz and Rabka areas in the Bystrica Subunit. It is located within medium- and thin-bedded sandy dominated turbidites of the Campanian–Paleocene Ropianka Formation. It is comprised of red shales laminated or interlayered with strongly bioturbated green shales. Exposures of the Farony Shale are observed along a distance of ~25 km, in the form of a narrow belt. The age of the variegated deposits is estimated based on agglutinated foraminifera to late Campanian–earliest Maastrichtian. Their deposition was associated with low-energy conditions and a temporary limitation of the supply of sandy material to the inner part of the Magura Basin.

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The Late Cretaceous Fucoid Marl of the Ropianka Formation in the Kąkolówka Structure (Skole Nappe, Outer Carpathians, Poland) : lithology and foraminiferal biostratigraphy

Waśkowska Anna, Joniec Andrzej, Kotlarczyk Janusz, Siwek Piotr

Annales Societatis Geologorum Poloniae

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2019

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Vol. 89, No. 3

259--284

EN

A 250-m-thick sedimentary succession dominated by siliciclastic deposits occurs in the Kąkolówka Structure of the Skole Nappe. The succession was deposited in the inner part of the Skole Basin during the Late Cretaceous. In position and age, it corresponds to the Kropivnik Fucoid Marl of the Wiar Member (a subdivision of the Ropianka Formation), which was comprehensively described in the external part of the Skole Nappe. In this study, the authors provide the first complete data set on the lithological development and biostratigraphy of the Kropivnik Fucoid Marl from the inner part of the Skole Nappe. The results are compared to previous data from the outer part of the Skole Nappe. In the Kropivnik Fucoid Marl of the Kąkolówka Structure, three main heterolithic facies associations are distinguished: shale-sandstone, marl-sandstone and sandstone-shale. The occurrences of hard, platy and soft marls within siliciclastic rocks are typical of the sections studied. The features observed indicate a turbiditic origin of the deposits studied, including the hard, platy marls. The allogenic material of the strata described includes the small, fragile tests of planktonic foraminifera, which were redeposited from the outer parts of the Skole Basin. Particularly large concentrations of planktonic foraminifera were observed in the hard, platy marls. They are less common in the soft marls and shales. In the Zimny Dział section, a diverse assemblage of benthic and planktonic foraminifera was found. The Kropivnik Fucoid Marl was dated as uppermost Campanian to lowermost Maastrichtian on the basis of planktonic foraminifera, which represent the Gansserina gansseri Zone. The agglutinated foraminiferal assemblages are representative for the lower part of the Rzehakina inclusa Zone and the co-occurrence of the Caudammina gigantea (Geroch) acme with Rzehakina inclusa (Grzybowski) was observed.

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Upper Cretaceous volcanoclastic deposits from the Haţeg basin, south Carpathians (Romania): K-Ar ages and intrabasinal correlation

Bojar A.-V., Halas S., Bojar H.-P., Grigorescu D., Vasile S.

Geochronometria

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2011

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Vol. 38, no. 2

182-188

EN

In order to constrain the age of the Upper Cretaceous continental Densuş-Ciula Formation from the Haţeg basin, South Carpathians, and correlate it with the other continental unit that occurs in the region, the Sânpetru Formation, we separated and dated by the K-Ar method biotites and amphi-boles from volcanoclastic deposits. The mineral phases analysed are from two tuff layers and volcanic bombs cropping out near Rachitova village. Two tuff layers from the Densuş-Ciula Formation give early Maastrichtian ages of 69.8š1.3 and 71.3š1.6 Ma, respectively. The ages determined for the tuff layers constrain the age of deposition for the Densuş-Ciula Formation and enable further correlations with the available palaeomagnetic data from the deposits occurring along the Sibişel Valley that be-long to the Sânpetru Formation. The volcanic bombs collected near to Răchitova village are andesites and dacites. The age determined by K-Ar method on hornblende separated from a volcanic bomb is 82.7š1.5 Ma, which is older than the underlying Campanian marine deposits in turbidite facies. This suggests that the volcanic bombs were re-deposited during the early Maastrichtian. Thus, the volcan-ics found at Răchitova have at least two origins: one type is related to an explosive synsedimentary volcanic activity, and the other type is represented by older andesitic/dacitic bombs, which most probably originate from a volcanic centre situated in the Haţeg region.

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Latest Campanian to Early Maastrichtian (Cretaceous) nautiloids from the white chalk of Kronsmoor, northern Germany

Wilmsen M., Esser K. J.

Acta Geologica Polonica

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2004

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Vol. 54, no. 4

489-498

EN

A well preserved and stratigraphically tightly constrained nautiloid fauna consisting of two species is described from the uppermost Campanian to Lower Maastrichtian white chalk section of Kronsmoor, northern Germany. Cymatoceras patens (KNER, 1848) occurs rather frequently in the Kronsmoor section; one specimen is from the Upper Campanian Micraster grimmensis/Cardiaster granulosus Zone, one from the upper Belemnella pseudobtusa to lowermost Belemnella obtusa Zone. The bulk of the material (nine specimens) is from the Early Maastrichtian B. obtusa and Belemnella sumensis zones. The species is known from the Upper Campanian to Lower Maastrichtian of northern Germany, The Netherlands, Poland, the Ukraine, and possibly Denmark. Cymatoceras loricatum (SCHLUTER, 1876) occurs in Kronsmoor (four specimens) in an interval comprising the Early Maastrichtian upper B. obtusa to B. sumensis zones.The species was hitherto only recorded from the uppermost Lower and Upper Campanian of Westphalia and Lower Saxony, Germany. Both species appear to be restricted to the Central European Subprovince of the temperate North European Province (Boreal Realm).