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Pseudo-shallow marine features in deep marine gravity-flow successions: lessons from the Menilite Beds at Skrzydlna (Oligocene; Western Outer Carpathians)

Wendorff Marek, Siemińska Aneta

Geotourism / Geoturystyka

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2023

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nr 1-2 (72-73)

79--80

EN

Quite common in publications devoted to the marine and lacustrine environments are differences of opinion on bathymetry of the basin receiving detrital sediment, especially when sedimentary structures are interpreted as indicators of specific depth-defined environments (following classic textbooks). However modern studies of deep-water environments, experimental work, modelling and numerous outcrop studies of ancient successions mitigate against such an approach. In this respect, the flysch succession of the Menilite Beds strata at Skrzydlna, which contains a variety of features that can confuse a cursory observer seems to serve as a universally applicable example. The succession at Skrzydlna records deposition in the western part of the synorogenic Dukla Basin during the Oligocene. The Menilite Beds are considered by most authors as deep marine deposits (the bathyal zone). The exposed section, almost 200-metre thick, is divided into three lithological intervals, each of which represents a radically different type of sedimentation. These are: i) a fine-grained association of terrigeonous and hemipelagic sediments; ii) infill of a canyon incised by about 40–50 m into the underlying strata, wider than outcrop and dominated by an olistostromal succession of debris flows with pebbles, boulders, slide and slump sheets; iii) succession of turbidites forming three fining-upwards sequences and ranging from thick, massive, amalgamated sandstones deposited by high-density flows in laterally migrating outcrop-scale channels, through ‘normal’ turbidites forming complete Bouma sequences (Ta-e), containing dunes and fining to Tce in the uppermost associations of thin-bedded sandstones and shales. These features suggest rapid uplift of the source area resulting in canyon incision and sudden onset of the olistostrome deposition that evolved upwards into proximal turbidite-fan sequence, which subsequently retrograded due to decreasing intensity of supply. The oldest interval (i) consists of predominantly finegrained facies, most characteristic of the Menilite Beds at their regional development. These are dark mudstones deposited in anoxic to dysoxic conditions and containing thin layers of fine-grained sandstones — turbidites with Bouma Tab; Tbc; Tabc; Tabe intervals, a 2–3 m thick intercalation of massive amalgamated sandstone, dark cherts, and locally silicified marls and limestones. The latter contain isolated lenses of medium-grained sandstone current ripple marks indicating three palaeocurrent directions. Two sets represent bipolar distribution of palaeocurrents, typical of shallow sea/ shelf sediments reworked by tidal currents. However, these are interpreted here as the products of tidal currents reworking bottom sediments of the bathyal zone, the case known from contemporary environments. In this context, the third direction, perpendicular to the bipolar flows does not represent reworking by littoral current on shelf but deep marine contour current. The main channel, or canyon (ii) incised into the slope sediments fed the depositional system with olistostrome deposits supplied from the rapidly uplifted source zone. Above there is a thinning upwards, turbidite sequence of four sub-complexes (A-D): A – conglomerate and sandstone fill three laterally migrating narrow, outcrop-scale erosional channels with a maximum depth of 15 m; B – two shallow (up to 2 m deep) distributary channels filled with very thick, massive or normally graded sandstones; C – turbidites Tb, Tc, Tbc with single occurrences of hummocky-like cross stratification and sandstone beds forming dunes at the mouth of distributary channels; D – less ordered interval of thick-, medium- and thin-bedded sandstones interbedded with mudstones, forming various incomplete sequences of Bouma intervals. Interbeds of hummocky-like cross stratification, commonly found on the shelf, are interpreted in the deep-sea environment as the effect of Kelvin-Helmholtz instability or other complex flow processes, e.g. reflections of turbidity currents. A few occurrences of ripplemarks symmetrical in outer shape show unidirectional cross-lamination in cross section. These were modified by erosion that could have resulted from occasional extremely violent storms or flow reflections off channel margins. In spite of the external shape reminiscent of symmetrical ripplemarks these features do not possess the internal structure of composite cross laminae characteristic for oscillatory reworking of sand by prolonged, rhythmic action of waves. Solitary current ripplemarks showing flow directions opposite to the main transport direction are antidunes or deposits of currents reflected/deflected by channel sides. In summary, in spite of geometrical and structural similarity to the features traditionally considered as formed on shelf, the structures described here, assessed in association with facies and evidence referred to in the introductory paragraphs, fall into the category of deposits known also from below the ‘normal’ wave base and below the shelf edge, i.e. in the slope region. Hence from deep-sea environment for which the occurrence of bipolar currents, dunes, hummocky cross-stratification and symmetrical ripplemarks are neither typical nor diagnostic, but do exist.

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An Oligocene olistostrome with exotic clasts in the Silesian Nappe (Outer Ukrainian Carpathians, Uzh River Basin)

Hnylko Oleh, Hnylko Svitlana, Heneralova Larysa, Tsar Maria

Geological Quarterly

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2021

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Vol. 65, No. 4

art. no. 47

EN

In the Ukrainian part of the Silesian Nappe (Outer Carpathians, Uzh River Basin) the exotic clast-bearing Uzhok Olistostrome (up to 60 m thick) occurs within the Oligocene Krosno Formation and underlies the Pikui Sandstone (Otryt Sandstone in Poland). The Uzhok Olistostrome consists of debris/grain/mud flow deposits with clasts of schist and bioclastic limestone. These deposits contain redeposited pelagic sediments with planktonic foraminifers including Parogloborotalia pseudocontinuosa (Jenkins), Ciperoella ciperoensis (Bolli), Globoturborotalita woodi (Jenkins), Chiloguembelina adriatica Premec Fucek, Hernitz Kucenjak and Huber. The age of the Uzhok Olistostrome based on planktonic foraminifers correlates with the middle Oligocene within the middle O2–O5 zones. The source area for the Uzhok Olistostrome and Pikui Sandstone was a mid-Oligocene intrabasinal palaeouplift (the Pikui Ridge) interpreted as the fore-bulge located in the Silesian Sub-basin ahead the emerging Outer Carpathian accretionary prism (including the Dukla Nappe and other West Carpathian inner flysch nappes).

3

Occurrence of clastic injectites in the Oligocene strata of the Carpathians and their significance in unravelling the Paleogene and Neogene evolution of the Carpathian orogeny (Poland, Ukraine and Romania)

Jankowski Leszek, Wysocka Anna

Geological Quarterly

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2019

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Vol. 63, No. 1

106--125

EN

The irregular distribution of sand injections, traditionally termed “dykes” in the Polish geological literature, within individual Carpathian units and within individual lithofacies were observed during long-lasting field works. Injectites have been observed in the Magura Beds and in the Inoceramian Beds of the Polish and Romanian Carpathians, and in the Central Carpathian Paleogene deposits. However, they are most common in the Oligocene-Miocene Menilite Beds, where they are typical and abundant, particularly in the Skole Unit. Two clastic injectite types were distinguished: sedimentary (S-type) and tectonized (T-type). Based on the occurrence and interpretation of these injectites a new two-stage conceptual model is proposed for the Polish segment of the progressive Oligocene-Miocene Carpathian orogenic belt evolution. Type S clastic injectites are interpreted as having formed in the compressional stage, during foredeep basin migration while depositional slope changes were taking place in the Late Oligocene to Early Miocene. Type T injectites are interpreted as having formed by reactivation of S-type injectites in the last, mainly strike-slip, phases of Carpathian orogenic belt formation.

4

Dinoflagellate cyst stratigraphy of the Popiele Member and Menilite Formation in the Boryslav-Pokuttya Nappe (Aksmanice, SE Poland)

Suchocka Arleta, Barski Marcin, Bieńkowska-Wasiluk Małgorzata

Geological Quarterly

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2019

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Vol. 63, No. 3

539--557

EN

In the Paratethys Sea, isolation, the development of anoxia and stratification of the water column resulted in deposition of organic-rich sediments. In the Western Carpathians (Central Paratethys) these sediments now lie within the Menilite Formation. Whereas the Eocene-Oligocene transition has been studied in the Western Carpathians and is documented by dinoflagellate cyst assemblages, the dinoflagellate cyst stratigraphy of the Menilite Formation members has been uncertain. The Popiele Member and the Menilite Formation exposed at Aksmanice (Boryslav-Pokuttya Nappe, Western Outer Carpathians) reflect palaeogeographic changes at the beginning of the Oligocene. These previously studied deposits have been assigned to lithostratigraphic units, though without biostratigraphic documentation. The age of the Menilite Fm. in the Carpathian sedimentary succession is particularly interesting due to the diachronous character of the facies development. In this study we provide biostratigraphic data based on well-preserved organic-walled dinoflagellate cyst assemblages. The marker taxa recovered indicate a Rupelian age (Early Oligocene) for the Menilite Fm. A different assemblage occurs in the Popiele Member underlying the Menilite Fm. Here, the dinoflagellate cysts are more diverse and abundant, and represented by typical Eocene taxa attributed to Areosphaeridium spp. and Charlesdowniea spp. The Popiele Member may be assigned to the Priabonian (Late Eocene).

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Depositional setting of the Oligocene sequence of the Western Carpathians in the Polish Spisz region : a reinterpretation based on integrated palynofacies and sedimentological analyses.

Filipek A., Wysocka A., Barski M.

Geological Quarterly

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2017

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Vol. 61, No. 4

859--876

EN

The research on the Oligocene succession of the Central Carpathian Paleogene Basin (CCPB) in the Kacwin region focused on sedimentological and palynofacies analyses. Observations were carried out in natural exposures along three streams flowing in the Polish Spisz: Kacwinianka, Łapszanka and Kacwiński. Three main groups of lithofacies have been distinguished: coarse-grained, mixed and sandy-grained, and fine-grained. The lithofacies are characterized by variable sedimentary structures, e.g. massive structure, horizontal lamination, ripple cross-lamination, hummocky cross-stratification, deformation structure. Sedimentological analyses showed that structures typical for turbidity currents and those characteristic of relatively shallow deposition (HCS, wave ripples) could coexist in the investigated succession interpreted as typical for turbidity currents influenced by storm waves. This indicates relatively shallow-water environments. The palynofacies analysis enabled identification of the following components: black wood, brown wood, cortex, resin, sporomorphs, cuticle, algae, dinoflagellates and AOM. A high proportion of black wood and low diversity of components point to an origin related to turbidity currents. Furthermore, results of the palynofacies analysis have allowed determining that, during the deposition of the CCPB sediments in the Polish Spisz area, the distance between the deposition area and the source area became relatively large. The biostratigraphic analysis of dinoflagellate cysts from the Podhale Basin (Szaflary, Zakopane, and lower Chochołów beds) indicates an Early Rupelian age. Moreover, kerogen analysis in the UV was applied for the first time to study the CCPB succession. As a result, reworking was documented, so far unrecognized by other methods, and the mutual verification of the obtained results was possible.

6

Elemental and organic carbon proxies for redox conditions of the Oligocene formations in the Ropa Tectonic Window (Outer Carpathians, Poland) : palaeoenvironmental implications

Wójcik-Tabol P.

Annales Societatis Geologorum Poloniae

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2017

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Vol. 87, No. 1

41--53

EN

The Oligocene Grybów Succession is recognized as a counterpart of the anoxic Menilite Formation. Its comprehensive geochemical investigations are made in the key sections of the Ropa Tectonic Window (the Grybów Unit, Polish Outer Carpathians). The maceral assemblages, dominated by land-plant liptinite, vitrinite and intertinite, correspond to kerogen types II and III. A Tmax vs. HI diagram shows terrestrial kerogen type II with various additions of type III and algal kerogen type I. A variation in δ13Corg. (from –25.21 to –27.38‰) may have resulted from variations in the composition of organic matter (the content of terrestrial vs. marine organic matter), controlled by depositional setting (turbidite vs. hemipelagic). The highest TOC contents are associated with an enhanced influx of land-derived organic matter. The redox-sensitive trace elements positively correlate with TOC and TS contents. Redox conditions varied between oxic and anoxic, as was concluded from TOC-TS, V/(V+Ni) and U/Th. The turbidity currents might have ventilated the bottom waters, especially more efficiently in the proximal zone of turbidite sedimentation. Moreover, oxygenated bottom waters may have also affected the concentration of trace metals, owing to migration of the redox interface downward within the sediments.

7

Palynology of Lower Oligocene brown coal and lowermost Middle Miocene sand deposits from the Łukowa-4 borehole (Carpathian Foredeep, SE Poland) : implications for palaeogeographical reconstructions

Gedl P., Worobiec E., Słodkowska B.

Geological Quarterly

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2016

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Vol. 60, No. 4

943--958

EN

Brown coal and overlying sand strata from the Łukowa-4 borehole, located in the northeastern sector of the Carpathian Foredeep in Poland, were studied for palynology. These strata are underlain by Upper Eocene sands, and covered by Middle Miocene rocks. Coal beds yielded infrequent sporomorphs and freshwater algae Botryococcus. The presence of the latter indicates that these deposits accumulated in a freshwater environment whereas sporomorph assemblages point to the presence of mixed forests with a significant portion of thermophilous taxa. Age of the coal beds has been established based both on the presence of species that appear for the last time in the Early Oligocene, and on the similarity with sporomorph spectra from the Lower Oligocene of the Polish Lowlands. Overlying sands yielded marine dinoflagellate cysts, which point to a marine sedimentary setting, and frequent sporomorphs. The latter indicate the presence of mixed mesophytic forests, bush swamps, swamp forests, and riparian forests in the vicinity of lacustrine environments. Stratigraphic analysis of dinoflagellate cyst and sporomorph assemblages suggests that the sands accumulated in early stages of Miocene transgression in the Carpathian Foredeep in the latest Early–early Middle Miocene. Our climatic interpretation of the sporomorph spectra suggests that the climate during deposition of the strata was relatively warm, although less frequent thermophilous taxa recorded in the Miocene sands suggest a slightly cooler climate than that deducted from the spectra yielded by the underlying Lower Oligocene coal beds. Correlation of Lower Oligocene coal beds with neighbouring coeval marine sands suggests diverse morphological conditions in the Carpathian foreland at that time, partly covered by a sea, and partly emerged. A similar, morphologically diverse basement in the Carpathian foreland favoured accumulation of Lower Miocene phytogenic deposits. A similar stratigraphic position of both Lower Oligocene and Lower Miocene coal beds in the Carpathian Foredeep may result in a false correlation of these strata devoid of fossils, which are commonly regarded as Miocene.

8

The Sokoliska Limestone, a new regional marker horizon of coccolith laminites in the Oligocene of the Outer Carpathians : diagnostic features and stratigraphic position

Ciurej A., Haczewski G.

Annales Societatis Geologorum Poloniae

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2016

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Vol. 86, No. 4

415--427

EN

Isochronous horizons of pelagic coccolith limestones are important regional stratigraphic markers in the Oligocene sequences of the Outer Carpathians. Three widely recognized limestone horizons are the Tylawa Limestones, the Jasło Limestone and the Zagórz Limestone horizons. Another regional marker horizon is described here, the Sokoliska Limestone horizon, situated between the Jasło Limestone and Zagórz Limestone horizons in the nannoplankton NP24 Zone. Its lithologic characteristics allow it to be distinguished from the other limestones, especially under the optical microscope. Its dark laminae are greatly enriched in non-calcareous material. The limestone contains tests of planktonic foraminifers, but these are much less abundant than in the Jasło Limestone. The boundaries with the marly shales above and below are often more gradational than is the case with the other limestone horizons.The Sokoliska Limestone has been recognized over a distance of ca.550 km in the Skole (Tarcãu) and Silesian units of the eastern and northern parts of the Outer Carpathians. Four sections of the Sokoliska Limestone horizonin the Polish and Romanian Carpathians are described; the exposure in the Sokoliska cliff of the Solinka River at Bukowiec was selected as the reference locality.

9

Depositional redox conditions of the Grybów Succession (Oligocene, Polish Carpathians) in the light of petrological and geochemical indices

Wójcik-Tabol P.

Geological Quarterly

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2015

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Vol. 59, No. 4

603--614

EN

This study details the petrology and chemistry of the Oligocene succession of the Grybów Nappe in its stratotype-locality in the Grybów tectonic window (Polish Carpathians). The section studied is composed of the Sub-Grybów Beds, the Grybów Marl Formation (GMF), and the Cergowa Beds, representing the middle to upper part of the Oligocene succession. The rocks studied consist of quartz, calcite, Na-plagioclase, muscovite and clay minerals (illite-smectite with 25–30% of smectite and kaolinite). Additionally, hematite occurs in the GMF and chlorite in the Cergowa Beds, respectively. The macerals assemblage of the GMF is dominated by landplant-derived compounds of liptinite, associated with minor amounts of vitrinite representing type II kerogen. The total organic carbon (TOC) content is between 0.45 and 6.16 wt.%. The δ13Corg values of the GMF vary between –27.1 and –27.9‰. The values of both carbon and oxygen isotopic ratios of carbonates range for δ13C from –1.1 to –4.3‰ VPDB, and for O from –1.5 to –4.8‰ VPDB. The concentrations of Co, U, Ni, As, and Mo are higher in the GMF than in the adjacent strata and positively correlate with TOC and S. Values of the TOC/S and V/V+Ni ratios are 0.7 to 3.5 and 0.67 to 0.78, respectively, and indicate anoxic conditions. The ratios of U/Th and V/Cr (0.3–2.2, 1.18–3.18, respectively) suggest the change of oxic conditions to reducing conditions occurred during the GMF deposition. This change could have been preceded by a plankton bloom, initiated by a nutrient-rich freshwater inflow that is inferred from the decrease of the δ13Ccarb values and the terrestrial detritus supply. Thermal alteration of the Grybów Succession is concluded on the basis of smectite illitisation and low δ18O values.

10

Calcareous nannofossils and foraminifera from the youngest deposits of the Siary Subunit (Oligocene, Magura Nappe, Polish Outer Carpathians)

Garecka M., Szydło A.

Annales Societatis Geologorum Poloniae

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2015

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Vol. 85, No. 1

205--219

EN

The calcareous nannoplankton and foraminifera from the Gładyszów Beds, regarded as the youngest deposits in the northern marginal Siary Subunit of the Magura Nappe in Poland, are characterized. The material investigated comes from outcrops in the vicinity of Gładyszów and from the Gładyszów PIG-1 borehole. The analysis allowed the establishment of the age of these deposits as not older than late Rupelian–early Chattian (the calcareous nannoplankton NP24 Zone). The taxonomic affiliations, environmental associations and preservation of the microfossils were analyzed to document the sedimentary processes and environmental conditions during the geotectonic transformation of the Magura Basin in the Oligocene. These microfossils also were compared with those reported from the terminal deposits of the Outer Carpathians and the Podhale Basin.

11

Age, internal stratigraphic architecture and structural style of the Oligocene–Miocene Numidian Formation of northern Tunisia

Riahi S., Soussi M., Ben-Ismail-Lattrache K.

Annales Societatis Geologorum Poloniae

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2015

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Vol. 85, No. 2

345--370

EN

The stratigraphy of the Numidian Formation of northern Tunisia and its internal organization are updated. Planktonic foraminifera point to a mainly Oligocene–Early Miocene age of this formation in the majority of the sections studied. Some key lithological horizons are recognized within the early Miocene succession, allowing lateral correlation between the outcrops of the Mogod and Kroumirie mountains. These include: (1) a conglomeratic interval, up to 1–2 m thick and rich in reworked glauconitic boulders, limestone fragments of the Tellian (Eocene) and pectinid bivalves; and (2) a relatively continuous glauconitic level. In the new stratigraphic scheme, the Zouza, Ben Metir and Sejnene sections represent the entire Numidian Formation. A lower unit (200–700 m thick), highly pelitic with subordinate sandstone beds was distinguished, overlain by an upper unit which is sandier, especially in its uppermost part (1,000–1,500 m thick). In the present study, these have been stratigraphically dated as Oligocene–Early Miocene p.p. (Rupelian–Chattian; P19–P21 zones) to Aquitanian (N4 Zone) and Miocene (Aquitanian–early Burdigalian; N4–N5 zones), respectively. In the areas studied, the sandy succession assigned to the Kroumirie Member begins with a sandstone unit with an erosional base or a major discontinuity, locally marked by conglomerates made up of various reworked components. It rests generally on a thick shale unit that characterises the upper part of the Zouza Member. The thinner, uppermost succession of the Numidian Formation represents the Babouch Member, dated as Burdigalian (N6–N7 zones). Within the framework of the new proposal, the total stratigraphic thickness of the Numidian Formation in northern Tunisia does not exceed 2,200–2,600 m. Internally, the Numidian Formation is transected by the Intra-Numidian Thrust and back-thrust faults, associated with faulted folds that are recognized in outcrop on different scales and in seismic sections. Along these thrust and/or reverse faults, the middle to upper Eocene deposits have undergone uplift and are exposed at the surface (e.g., Dowar Larmel in Meloula-Tabarka, Gaâret Sejnene and Sidi M’chreg sections).

12

Source rocks for heavy minerals in lower part of Menilite Formation of Skole Nappe (Polish Flysch Carpathians), based on study of detrital garnet and tourmaline

Salata D.

Annales Societatis Geologorum Poloniae

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2013

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Vol. 83, No. 1

1--17

EN

The study focused on the chemistry of detrital garnet and tourmaline from sediments of the Boryslav and Kliva Sandstone types in the Oligocene part of the Menilite Formation of the Skole Nappe (Western Outer Carpathians, Poland), with regard to provenance. Almandine and almandine-pyrope compositional varieties are the most common garnets, with minor almandine-pyrope-grossular garnet. Scarce garnet grains, with grossular and spessartine as the dominant end-members, are also present. The tourmaline belongs to the alkali tourmaline principal group and represents the schörl-dravite series. The detrital garnet and tourmaline display strong, compositional similarities to minerals, occurring in igneous and metamorphic rocks of the Bohemian Massif, as well as to detrital grains, deposited within the internal basins of the massif. This suggests that the primary rocks for the garnet and tourmaline may be crystalline complexes of the Bohemian Massif. However, other uplifted areas, similar to the complexes of the Bohemian Massif, cannot be ruled out. Such hypothetical areas could be located in the northern foreland of the Carpathian basins. Euhedral tourmaline and other minerals, occurring in the heavy- mineral assemblages studied, most probably were derived from eroded and presently not exposed, crystalline complexes, originally situated in the Skole Basin foreland or within the basin.

13

The Tylawa Limestones – a regional marker horizon in the Lower Oligocene of the Paratethys : diagnostic characteristics from the type area

Ciurej A., Haczewski G.

Geological Quarterly

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2012

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Vol. 56, No. 4

833-–844

EN

Three units of laminated coccolith limestone are used as regional chronohorizons in the Oligocene of the Outer Carpathians. Two of them – the Tylawa Limestones and the Jasło Limestone display a similar type of lamination and their discrimination is in some cases problematic. We provide a detailed mesoscopic and microscopic lithological description of the Tylawa Limestones from the type locality at Tylawa and from Rudawka Rymanowska – the best exposure in the Polish Carpathians. The finely laminated limestone layers are up to 5.5 cm thick and are dispersed through a section more than 100 m thick. They are grouped in clusters. They differ from the younger Jasło Limestone in: (1) an absence of foraminifers, (2) a mass occurrence of Reticulofenestra ornata Müller, (3) the presence of voids after pennate diatoms, (4) dark laminae which are more pronounced than in the Jasło Limestone.

14

The miniature echinoid trace fossil Bichordites kuzunensis isp. nov. from early Oligocene prodelta sediments of the Mezardere Formation, Gokceada Island, NW Turkey

Demircan H., Uchman A.

Acta Geologica Polonica

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2012

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Vol. 62, no. 2

205-215

EN

The pascichnial trace fossil Bichordites kuzunensis isp. nov. occurs as an epichnial complex structure in early Oligocene prodelta sediments of the Thrace Basin in Gokceada Island, northwest Turkey. It displays characteristics of irregular echinoid burrows such as overall shape and a double meniscate filling with a chevron dorsal suture, in addition to the feature typical of the so far monospecific Bichordites Plaziat and Mahmoudi, 1988, that is a single central core around a single drainage tube. Its miniature size can be related to the small size of the tracemaker (ontogenic feature) or to its dwarfism in a stressed deltaic environment (palaeoecological feature). Its occurrence indicates a period of fully marine conditions during accumulation of the deltaic sediments of the Mezardere Formation.

15

Radiometric dating of the Tertiary volcanics in Lower Silesia, Poland. VI. K-Ar palaeomagnetic data from basaltic rocks of the West Sudety Mountains and their northern foreland

Birkenmajer K., Pécskay Z., Grabowski J., Lorenc M. W., Zagożdżon P. P.

Annales Societatis Geologorum Poloniae

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2011

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Vol. 81, No 2

115-131

EN

This article presents the sixth and final contribution in a series of papers focused mainly on the K-Ar dating of the Oligocene and Neogene (Miocene and Pliocene) intraplate basaltic volcanics of the Lower Silesia, SW Poland. The present paper includes 22 new K-Ar dates from the West Sudety Mountains and their northern foreland. The K-Ar dates range from 30.7 to 22.2 Ma. The data are supplied with geological description of the sampled outcrops, petrographic, geochemical and palaeomagnetic data of the analysed samples. Palaeomagnetic investigation confirmed the existence of two important volcanic episodes distinguished already in 1997: the reversed polarity Odra Event (mean age 28.2š1.2 Ma), and the normal polarity Gracze Event (mean age 26.28š1.8 Ma).

16

Taphonomy of Oligocene teleost fishes from the Outer Carpathians of Poland

Bieńkowska-Wasiluk M.

Acta Geologica Polonica

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2010

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Vol. 60, no. 4

479-533

EN

The Oligocene ichthyotaphocoenoses from the Outer Carpathians of Poland are dominated by skeletons of actinopterygian (only teleost) fishes. Their taphonomy was studied in six localities of the Menilite-Krosno Series (Błażowa, Jamna Dolna 1, Jamna Dolna 2, Rudawka Rymanowska, Wola Czudecka, Wujskie). Over 1700 specimens of variably complete fish skeletons, representative of 20 actinopterygian families, were studied. The taphonomic analysis of the skeletal disarticulation and its pattern, deformations of the vertebral column (curved, broken), arrangement of jaws and fins, the spatial array of skeletons with regard to the embedding sediment, as well as identification of unusually preserved specimens, indicate that all of the ichthyotaphocoenoses have resulted from a long-term accumulation of fish carcasses at the burial place, at a very low sedimentation rate, under anoxic conditions in, and above, the sediment/water interface. Two assemblages from the Tylawa Limestone Horizon have acquired their unusually good preservation state due to the penetration of calcium carbonate into soft tissues of corpses at the burial place. in other deposits (shales, marls) the fish skeletons are more or less disarticulated as a result of decay in a calm environment. each of the ichthyotaphocoenoses displays some features indicative of mass mortality events (e.g. high density of individuals, the presence of individuals with jaws agape, high number of juveniles); none of them has a set of features indicating it unequivocally. The cause and/or conditions of death were not the same for all individuals. Only some individuals died instantaneously during mass mortalities, whereas the majority died over a period of time as a result of senility, diseases, or other circumstances. all of the ichthyotaphocoenoses show features typical of both necro- and thanatocoenoses. The associated flora and fauna, e.g., amphipods, land-derived dragonflies and bird feathers, indicate that the taphocoenoses originated as a result of accumulation of biotic remains from various environments. Fishes and associated remains settled on the bottom successively, and thus their assemblages display features typical of necrocoenoses. evidence of fish predation is reported for the first time from the Menilite-Krosno Series of Poland.

17

Phanerozoic paleoenvironment and paleolithofacies maps : Cenozoic

Golonka J.

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

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2009

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T. 35, z. 4

507-587

EN

The paper presents the detailed plate tectonic, paleogeographic, paleoenvironment and plaeolithofacies maps for seven Cenozoic time intervals. Thirty five maps, generated using PLATES and PALEOMAP programs, contain information about plate tectonics, paleoenvironment, and paleolithofacies during Paleocene, Eocene, Oligocene, Miocene and Pliocene, time slices. The spatial reconstruction of basin architectures during their origin, expansion, closure and inversion as well as the dynamic of intrabasinal ridges were obtained by palinspastic modeling. This modeling utilized paleomagnetic data and stratigraphic-facies analysis of basins and ridges. Information contained within global and regional papers were selected and posted on the maps. The detailed paleoenvironment and plaeolithofacies zones were distinguished within the basins. The paleogeographic maps illustrate the geodynamic evolution of Earth from Late Cretaceous to Neogene, spreading and origin of new oceans, oceans closing, collisions, continents accretion and origin of new supercontinents.

PL

Artykuł przedstawia szczegółowe mapy paleogeograficzne dla siedmiu przedziałów czasowych w obrębie kenozoiku. Trzydzieści pięć map, skonstruowanych przy użyciu programów PLATES i PALEOMAP, zawiera informacje dotyczące tektoniki płyt, paleośrodowiska i paleolitofacji w czasie paleocenu, eocenu, oligocenu, miocenu i pliocenu. Przestrzenną rekonstrukcję architektury basenów w okresie ich powstawania, ekspansji, zamykania i inwersji oraz analizę dynamiki grzbietów śródbasenowych uzyskano, wykonując modelowanie palinspastyczne, przy uwzględnieniu badań paleomagnetycznych oraz analizy stratygraficzno-facjalnej basenów i rozdzielających je grzbietów. Informacje zawarte w szeregu globalnych i regionalnych prac zostały wyselekcjonowane i naniesione na mapy. W obrębie basenów wydzielono poszczególne strefy paleośrodowiskowe i paleolitofacjalne. Mapy paleogeograficzne ilustrują geodynamiczną ewolucję Ziemi od późnej kredy po neogen, rozrost (spreding) i tworzenie się oceanów, zamykanie się oceanów, kolizje, łączenie się kontynentów i tworzenie się nowych superkontynentów.

18

A new occurrence of sharks in the Menilite Formation (Lower Oligocene) from the Outer (Flysch) Carpathians of Poland

Bieńkowska-Wasiluk M.

Acta Geologica Polonica

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2009

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Vol. 59, no. 2

235-243

EN

Two newly recognized sections (Jamna Dolna 2 and Wola Czudecka) of the Lower Oligocene Menilite Shales (Menilite Formation) in the Polish Outer (Flysch) Carpathians have recently yielded a small shark assemblage. It comprises teeth of Heptranchias howelli (Reed, 1946), not hitherto reported from Europe, as well as the remains of other sharks (teeth of ?Mitsukurina, Alopias, gillrakers of Cetorhinus) all contributing to the fish assemblage of the Carpathian Menilite Formation, which has long been famous mostly for its teleost content. The life environment of the studied sharks and the basin bottom conditions are briefly discussed.

19

The stratigraphy of the Oligocene deposits from the Ropa tectonic window (Grybów Nappe, Western Carpathians, Poland)

Oszczypko-Clowes M.

Geological Quarterly

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2008

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Vol. 52, No 2

127-127

EN

The Ropa tectonic window of the Magura Nappe is composed of Oligocene deposits that belong to the Grybów Nappe. The youngest deposits of the Ropa tectonic window are correlated with calcareous nannoplanton zones NP24 and NP25. The NP24 zone interval was determined in the Sub-Grybów Beds and in the Grybów Marl Formation, whereas the Krosno (Cergowa) Beds belong to zone NP25. This age determination corresponds well with that of other Magura Nappe tectonic windows and also with the southern part of the Silesian and Dukla nappes. The facies and age of the Krosno Beds from the Grybów succession record the termination of Fore-Magura basins. The Grybów Nappe deposits in the Ropa tectonic window are overthrust by Cretaceous-Eocene formations of the Magura Nappe.

20

Wykształcenie facjalne warstw krośnieńskich w oknie tektonicznym Mszany Dolnej (polskie Karpaty Zachodnie)

Stadnik R.

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

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2007

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T. 33, z. 4

375-393

PL

Przedmiotem opracowania są warstwy krośnieńskie odsłaniające się w oknie tektonicznym Mszany Dolnej w obrębie jednostki dukielskiej. Utwory te wykształcone są głównie w litofacji piaskowców, piaskowców z mułowcami, mułowców z piaskowcami oraz mułowców. Podczas analizy sprofilowanych odsłonięć brano przede wszystkim pod uwagę następujące cechy: wykształcenie litofacjalne, miąższości ławic, procentowy udział piaskowców w stosunku do skał zbudowanych z frakcji drobniejszych, wysortowanie materiału okruchowego, a także rodzaj powierzchni spągowych i stropowych ławic oraz obecność sekwencji negatywnych i pozytywnych w profilu. W konsekwencji rozpoznano środowisko sedymentacji tych utworów. Wykazano, że warstwy krośnieńskie powstawały w obrębie głębokomorskich stożków, w strefie stożka zewnętrznego, w subśrodowisku lobów depozycyjnych, obrzeżenia lobu i obrzeżenia stożka. Na podstawie próbek mikrofaunistycznych oznaczono wiek warstw krośnieńskich na oligocen (zona NP24). Pomierzone kierunki paleotransportu wskazują, że transport materiału okruchowego odbywał się z kierunku południowo-zachodniego na północny wschód.

EN

The present author studied the Krosno beds outcropped in the Mszana Dolna tectonic window within the Dukla Unit. These deposits are mainly developed as sandstones, sandstones with mudstones, mudstones with sandstones and mudstones. The following features: lithofacial development, thickness of layers, the percentage of sandstones in relation with the fine-grained rocks, clastic sediments sorting as well the character of bottom and top surfaces of layers and the presence of the positive and negative sequences in a profile were taken into account for the analysis of the geological profiled outcrops. Such sedimentological features of the Krosno beds indicate their depositional environment connected with the deep-sea fans, in the area of the lower fan, in the subenvironment of the depositional lobes, the lobe fringe and the fan fringe. Based on the microfossils the age of the Krosno beds has been indicated as Oligocene (zona NP24). The measured directions of the palaeotransport show that the distribution of the clastic material took place from the SW to the NE.