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The tectonics and stratigraphy of the transitional zone between the Pieniny Klippen Belt and Magura Nappe (Szczawnica area, Poland)

Jurewicz E., Segit T.

Geology, Geophysics and Environment

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2018

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Vol. 44, no. 1

127--177

EN

The Pieniny Klippen Belt is a narrow, complex structure stretching along a tectonic boundary between the Central and Outer Carpathians. Its formation involved two main evolutionary stages, the first, related to Late Cretaceous-Paleocene folding and thrusting, and the second, associated with Miocene orogenic events in the Outer Carpathians. Interactions between the Pieniny Klippen Belt and Outer Carpathians during both the sedimentation and deformation stages have resulted in the establishment of a peri-klippen transitional zone (named the Šariš Transitional Zone), in which the tectonic deformation effects gradually decrease towards the north. The stratigraphy and tectonic position of this zone have been controversial for decades. The key stratigraphic problems concern 1) the lithologic identity and position of the Szlachtowa (“black flysch”), Opaleniec and Pieniny formations and 2) the relation of the Jarmuta Formation, associated mainly with the Šariš Transitional Zone, to the Szczawnica and Zarzecze formations of the Magura Nappe. We provide an early Paleogene dinoflagellate cyst stratigraphic record of deposits that, according to some recent reinterpretations, represent the Neogene “Kremna Formation”. The legitimacy of new lithostratigraphic assignments of the “Kremna Formation” at Jaworki is put into question upon the basis of the primacy of units introduced for the same strata earlier.

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The North European Platform suture zone in Poland

Golonka J., Pietsch K., Marzec P.

Geology, Geophysics and Environment

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2018

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Vol. 44, no. 1

5--16

EN

The authors interpret the structure of the Central Carpathian-North European plates suture zone in Poland, where three main Carpathian tectonic units: the Central Carpathian, Pieniny Klippen Belt (PKB) and Outer Carpathian are present. In general, the PKB follows this zone. Several deep bore-holes were drilled in this region and the seismic lines were tied to bore-hole data and geological maps. The Polish PKB belongs to the complex geological structure stretching from Vienna in Austria to Romania. The rocks included in the PKB tectonic components were deposited within the paleogeographic realm known as the Alpine Tethys, mainly during the Jurassic-Early Cretaceous times. Both strike-slip and thrust components occur within the Polish section of the PKB. The strongly tectonized, few kilometer wide PKB zone is limited by a flower structure marked by two major faults, linked to the strike-slip zone. These faults reach the North European Platform (part of the North European Plate). The flysch sequences, arranged into a series of north-vergent thrust-sheets, constitute the main component of the PKB in the survey zone. They contain olistoliths, which are mainly Jurassic-Early Cretaceous in age. The PKB tectonic components of different age, strike-slip, thrust as well as toe-thrusts and olistostromes are mixed together, giving the present-day mélange character of this belt, where individual units are hard to distinguish. Two olistostrome belts (mélange units) exist within the PKB structure. The seismic lines show the Central Carpathian Paleogene rocks covering the Paleozoic Central Carpathian Basement south of the PKB. The Subtatric covers the High-Tatric autochthonic and allochthone rocks. The Central Carpathian Plate is thrust over the North European Platform in the Podhale region. The allochthonous Outer Carpathians consist of several nappes (thrust-sheets) verging northward. They are thrust over each other and over the North European Platform which dips gently southward.

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Geology of the Magura Nappe in the Osielec area with emphasis on an Eocene olistostrome with metabasite olistoliths (Outer Carpathians, Poland)

Cieszkowski M., Kysiak T., Szczęch M., Wolska A.

Annales Societatis Geologorum Poloniae

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2017

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Vol. 87, No. 2

169--182

EN

The Magura Nappe in the Polish sector of the Outer Carpathians consists of four tectonic subunits characterized by differing development of facies. From the south to the north, they include the Siary, Rača, Bystrica and Krynica subunits. The sedimentary succession in the Rača Subunit in the vicinity of the village of Osielec is composed of Campanian–Palaeogene flysch deposited in the Magura Basin. In this succession, the Middle Eocene Pasierbiec Sandstone Fm consists of thick-bedded sandstones and conglomerates with occasional intercalations of thin-bedded shale-sandstone flysch. Within the Pasierbiec Sandstone Fm at Osielec there is an olistostrome, rich in pebbles and cobbles of exotic rocks. In addition, large blocks of Neoproterozoic metabasites and boulders of Palaeogene organogenic limestones were found. The discovery of metabasites raised the possibility that the rocks in question could be evidence of supposed oceanic crust in the basement of the Magura sedimentary basin, because of the suggestion that they represent the Alpine orogenic cycle. This concept was abandoned when investigations of the absolute age of the metabasites gave a date of ca. 600 Ma. In the Osielec area, there are two tectonic thrust sheets in the Rača Subunit, namely the Osielczyk Thrust Sheet in the north and the Bystra Thrust Sheet in the south; they are folded and cut by a transverse system of strike-slip and oblique faults. The Osielczyk Thrust Sheet was overthrust northwards on to the Siary Subunit.

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Biostratigraphy and depositional anatomy of a large olistostrome in the Eocene Hieroglyphic Formation of the Silesian Nappe, Polish Outer Carpathians

Waśkowska A., Cieszkowski M.

Annales Societatis Geologorum Poloniae

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2014

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Vol. 84, No. 1

51--70

EN

The study focuses on a large olistostrome unit (~200 m thick and 4 km in strike-parallel extent) embedded in the Mid-Eocene shaly Hieroglyphic Formation of the Silesian Nappe, exposed in the Rożnów Lake area. Foraminifer biostratigraphy and petrographic comparisons are used to identify the provenance of olistoliths. The olistostrome is tripartite with respect of its olistolith composition. The lower part of the olistostrome abounds in olistoliths of sandstones derived from the Early Eocene turbiditic Ciężkowice Formation, whereas the middle part is dominated by olistoliths of Early Eocene bathyal mudshales. The upper part contains olistoliths of Middle Eocene turbiditic “banded sandstones”, known from the Hieroglyphic Formation and deposited in the bathyal zone above the CCD. The bathyal provenance of the olistostrome contrasts with the abyssal origin of the hosting green shales. The olistostrome unit is inferred to be composite, emplaced in the earliest Bartonian or at the Lutetian/ Bartonian transition by a series of at least three large debris flows that closely followed one another. Biostratigra- phical data and slump-fold vergence suggest resedimentation from the bathyal northern slope of the Silesian Cordillera that bounded the abyssal Silesian Basin to the south. Northward movement of the thrust-formed cordillera must have warped up the base-of-slope deposits of the Ciężkowice Formation, causing their gravita- tional collapse. This event destabilized the former lower-slope muddy deposits, resulting in a second phase of resedimentation by retrogressive slumping, which led to the collapse of mid-slope sandy turbidites. The slope failures involved contemporaneous Mid-Eocene sediment with an admixture of foraminifers derived from the upper slope or shelf margin and with exotic bedrock debris shed from the eroded cordillera crest. The catastrophic multi-phase emplacement of the olistostrome marked the last major thrusting pulse of the second (Late Cretaceous–Late Eocene) stage of tectonic evolution of the Outer Carpathian accretionary prism.

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Olistolity w serii śląskiej i ich związek z fazami rozwoju basenu śląskiego

Cieszkowski M., Golonka J., Krobicki M., Ślączka A., Waśkowska A., Wendorff M.

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

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2009

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T. 35, z. 2/1

13-21

EN

Olistoliths of various ages, provenance and dimensions are known in all of the higher-rank tectonic units of the Outer Carpathians. Their occurrences at various stratigraphic levels (Late Jurassic - Early Miocene) are related to different stages of development of the flysch basins, from the stage of rifting to post-rifting, through the orogenic phases, and further to the post-orogenic period.

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Micropalaeontological analysis of olistoliths from the Wieliczka Salt Mine (Outer Carpathians, Poland)

Machaniec E., Zapałowicz-Bilan B.

Studia Geologica Polonica

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2005

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Vol. 124

273-284

EN

Upper Cretaceous variegated marls of a Węglówka-type facies are exposed in the form of olistoliths within the Zuber-type salt deposits at the higher exploitation level of the "Kunegunda" Drift in the Wieliczka Salt Mine. This is the southernmost zone of occurrence of redeposited blocks of the Carpathian flysch sediments within the Miocene salt deposits of the Carpathian Foredeep. The variegated marls contain considerably diversified assemblages consisting only of small benthic foraminifera, including both agglutinated and calcareous taxa. Basing on the ranges of the characteristic species the variegated marls in the "Kunegunda" drift are dated as Turonian-Campanian. Two zones of benthonic agglutinated foraminifera have been recognised: the Uvigerinammina jankoi and Goesella rugosa zones. The foraminiferal assemblage of the youngest segment of the Węglówka marls is dominated by calcareous benthonic taxa with Stensioeina gracilis Brotzen as the most numerous species. Its presence indicates a Campanian age of this part of the studied deposits.