Browsing by Subject "foraminifera"

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Access status: Open Access ,
A record of Eocene subaqueous large-scale mass movements in the external Tethys Ocean (Skyba Nappe, Outer Carpathians, Ukraine)
(Wydawnictwa AGH, 2025) Waśkowska, Anna; Hnylko, Svitlana; Kowal-Kasprzyk, Justyna; Golonka, Jan; Słomka, Tadeusz; Hnylko, Oleh; Heneralova, Larysa; Pilarz, Monika
Studies were carried out on the Popeli Beds, which were mainly deposited by mass movements along the northern slope of the Tethys Ocean and form an olistostrome sequence occurring within Paleogene deposits. The analysis focuses on the deposits exposed in the northern limb of the Pobuk Syncline – the structural element of the Oriv Skyba – in the external zones of the Skyba (Skole) Nappe. Structural, lithological, sedimentological and paleontological studies allowed for the identification and characterisation of the olistostrome sequence and revealed its structure. Six individual olistostrome complexes were distinguished and described in detail. Five of these are gravelly mudstoneswith oversized clasts, overlain by medium-bedded mudstones and sandstones, the last one consists of deformed packages of thin bedded mudstones and sandstones. The olistostrome sequence is composed of a wide range of lithological and stratigraphic components, including Tithonian – Berriasian shallow- water limestones (so-called Štramberk-type limestones), Upper Cretaceous limestones, sandstones, and siliceous rocks, as well as Paleogene mudstones, sandstones, limestones, and marls. Biostratigraphic analysis of foraminifera indicates the Bartonian as the time of displacement. The olistostrome niche migrated downslope from a lower shelf-upper slope position characterized by marl sedimentation, to slope areas dominated by turbidite sedimentation.
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.
Access status: Open Access ,
Paleogene of the Magura Nappe adjacent to the Pieniny Klippen Belt between Szczawnica and Krościenko (Outer Carpathians, Poland)
(Wydawnictwa AGH, 2014) Golonka, Jan; Waśkowska, Anna
The present authors investigated the Paleogene deposits of the internal zone of the Magura Basin known as the Krynica Subunit or Krynica zone in Poland. These deposits crop out in the peri-Pieniny zone, in the area between Szczawnica and Krościenko. The oldest flysch deposits belong to the Paleocene - Lower Eocene Szczawnica Formation. This formation is covered by thin-bedded turbidites of the Eocene Zarzecze Formation locally with intercalations of the thick-bedded sandstones of the Krynica Member and Łęcko-type marls. The youngest rocks in this area belong to the Eocene-Oligocene Magura Formation. The Zarzecze Formation occupies a large part of the Krynica zone of the Magura Nappe border structure. Some deposits previously distinguished as the Szczawnica Formation were transferred to the Zarzecze Formation. The foraminiferal assemblages confirm the Eocene age of these deposits.
Access status: Open Access ,
Potential source rocks in the Ropianka Formation of the Magura Nappe (Outer Carpathians, Poland) - geochemical and foraminiferal case study
(Wydawnictwa AGH, 2018) Waśkowska, Anna; Golonka, Jan; Machowski, Grzegorz; Pstrucha, Ewa
To optimize exploration for new hydrocarbon accumulations in the Polish Outer Carpathians, it is necessary to concentrate attention on identification of hydrocarbon accumulations of the »shale-gas« type. Results of recently completed analysis suggested new such possible targets in the Magura Basin, preserved in the Outer Carpathian Magura Nappe. Analysis of the preliminary results of paleoenvironmental and geochemical studies of these shales is the subject of this paper. Micropaleontological and geochemical study was conducted on the 300 m thick Świątkowa Member, the uppermost part of the Ropianka Formation located in the external, northernmost Siary Zone. This member is composed of thin- and medium-bedded sandstones interbedded by green, brown, black and dark-gray shales. Poor and changeable oxygenation is reflected in the composition of foraminiferal assemblages. A negative correlation between the TOC content and numbers and diversity of foraminifera is observed. The paleogeographic position and paleoenvironment assessment indicates that the Siary Zone fulfills certain conditions for organic productivity and preservation during the deposition of the Ropianka Formation.
Access status: Open Access ,
The Eocene Hieroglyphic beds and Green shales in the Rożnów Lake area (Silesian Nappe, Outer Carpathians) - facies development and biostratigraphy
(Wydawnictwa AGH, 2014) Waśkowska, Anna
In the lithostratigraphic section of a sedimentary sequence of the Silesian Nappe in the area of Rożnów Lake, the strata that occur above the Ciężkowice sandstone and below the Globigerina marls are represented by a relatively thin unit informally named the Hieroglyphic beds and a succeeding thick complex of so-called Green shales. The Hieroglyphic beds, deposited over a short time interval during the Lutetian time (Reticulophragmium amplectens zone), are followed by the Green shales that were deposited from the Lutetian to the Priabonian (Reticulophrgamium amplectens, Ammodisus latus, Reticulophragmium rotundidorstum zones). This work describes the foraminiferal assemblages, on the basis of which, the age of the Green shales was established that in the area of Rożnów Lake. Deposition of the Green shale unit started in the Lutetian, while in other regions of the Silesian Basin it is documented from the Priabonian. The upper boundary of the Green shales is isochronous and defined by the base of the calcareous horizon of a specific type of marls known as the Globigerina marls.