Browsing by Subject "Outer Carpathians."

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Access status: Open Access ,
Lithistid spicules in the sediments of the Turonian Variegated Shale in the Silesian Nappe, Polish Outer Carpathians
(Wydawnictwa AGH, 2014) Okoński, Szymon; Górny, Zbigniew; Bąk, Marta; Bąk, Krzysztof
Turbiditic silty and sandy intercalations in the Turonian Variegated Shale from the Silesian Nappe (Polish Outer Carpathians) contain numerous sponge spicules among siliciclastic fine-grained particles. The highest amount of spicule admixture is nearly 50%. In such layers, they create spiculitic sublitharenite microfacies. These sponge spicules contain forms belonging mostly to the Lithistida group (97% of morphotypes), with a small admixture of spicules from the Hexactinellidae group. Tetraclones with a high content of different types of triaenes dominate among desmas, what indicates the dominance of sponges from subfamily Tetracladina. The preservation state of spicules is generally poor. The Variegated Shale deposits that contain the sponge spicules were accumulated in a deep sea basin, below the calcium compensation depth. Most probably, the spicules were derived from loose material accumulated earlier in various parts of the basin slopes, from which they were exhumed and again redeposited by turbidity currents during the Turonian times.
Access status: Open Access ,
Paleogene microfossils from the submarine debris flows in the Skole basin (Polish and Ukraine Outer Carpathians)
(Wydawnictwa AGH, 2014) Szydło, Andrzej; Garecka, Małgorzata; Jankowski, Leszek; Malata, Tomasz
Biostratigraphic analysis of fossils material has allowed the documentation of sediment gravity flows in the Skole basin during the Paleocene and Eocene times, and also in the Eocene-Oligocene transition. This most external basin of the NE Outer Carpathians was a marginal sea especially sensitive to geotectonic instability and relative sea-level change, favoring the development of down slope movements at these times. The dominance of calcareous forms in foraminifera, and a large share of redeposited species among the nanno- and microfossils indicate a close relationship of sediments containing them with the shelf environment and documents not too long transport. Additionally the recycled forms are often well preserved, indicating that the rock contained in flows were only plasticized and hydrated while the material itself was not a subject of significant mechanical processing in contrast to that one, which directly documented down slope moving. The latter forms are bad preserved and their fossil remains are usually corroded, partially dissolved and broken during this process. In addition, the planktonic forms including foraminifera, calcareous dinocysts and nannoplankton allow documenting the time of the final deposition of the sediment transported on slope.