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Siliciclastic input into Upper Cenomanian synorogenic sediments of the High-Tatric Unit, Central Western Carpathians (Tatra Mountains); petrography, geochemistry and provenance

Wolska A., Bąk K., Bąk M.

Geological Quarterly

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2016

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Vol. 60, No. 4

919--934

EN

The Upper Cenomanian mixed siliciclastic-carbonate succession of the High-Tatric Unit was deposited during the initial stage of basinal closing of the Tatric area, part of the Zliechov (Križna) Basin (Inner Carpathian domain). As a result of tectonic activity taking place at the northern Veporic margin, pulses of siliciclastic input interrupted marine carbonate sedimentation. The siliciclastic material, part of the Zabijak Formation, has been studied along two sections (Pisana Gully and Zdziarski Gully) in the Western Tatra Mountains. Microfacies, petrographic and geochemical analyses reveal a variability of siliciclastic material composed of various types of granitoids and medium- or high-grade metamorphic rocks, with schists and gneisses. Such interpretation is confirmed by the results of elemental chemical analyses, in which immobile trace elements, such as REE, Th, Cr, Co, Zr, and Y were used as indices for sediment provenance. The parent rocks sustained moderate to intense chemical weathering, documented by chemical weathering indices (CIA, PIA, CIW, R). The weathering occurred in a humid climate with relatively high precipitation that caused strong leaching of particles. Chemical indices related to sorting processes suggest that the recycling of the source material was a minor significance. The siliciclastic input displays a waning upward tendency in the sections, which can be associated with diminishing of the source area by gradual inland progradation of a carbonate platform, caused by a global sea level rise during the Late Cenomanian.

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Budowa geologiczna masywu Ciemniaka na podstawie danych z Jaskini Małej w Mułowej (Tatry Zachodnie)

Szczygieł J., Borowska U., Jaglarz P.

Przegląd Geologiczny

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2014

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Vol. 62, nr 7

349--355

EN

The Mała Cave in Mułowa has been explored to a depth of 555 m at the beginning of the 21th century. It makes a good opportunity to review the knowledge on the geological structure of the Ciemniak Massif. The geological research was performed in two main conduits of the cave. The Mała Cave in Mułowa developed in Lower and Middle Triassic carbonates belonging to the dziary Unit (CzerwoneWierchy Nappe – part of the High-Tatric Allochthon), as well as in marly shales of the Zabijak Formation and limestones of the Wysoka Turnia Limestone Formation belonging to the High-Tatric Autochthon. The cave is the second outcrop of the lower limb of the main syncline of the dziary Unit. It follows that the dziary Unit in the Ciemniak area is represented by a recumbent, open syncline with completely preserved both limbs. This syncline is open northtoward . The fold axes are subhorizontal and the axis surface is inclined ~37o N. From a depth of 300 m (below the entrance), the cave was formed at the contact of Cretaceous rocks belonging to the autochthonous cover and Triassic rocks of the dziary Unit.

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Facies and sedimentary environment of the carbonate-dominated Carpathian Keuper from the Tatricum domain: results from the Dolina Smytnia valley (Tatra Mts, Southern Poland)

Jaglarz P.

Annales Societatis Geologorum Poloniae

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2010

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Vol. 80, No 2

147-161

EN

The paper focuses on an interpretation of sedimentary and early diagenetic environment in the carbonate-dominated uppermost Ladinian-Norian succession from the Tatricum domain of the Tatra Mountains as well as its controlling factors. Limestones with cherts are the product of pedogenic processes, formed during long-term exposures of carbonate substrate. Chalcedony cherts were formed during relatively early diagenesis of pedogenic limestones. Dolostones and dolomitic mudstones were deposited in a kind of salt marshes. Pseudomorphs after sulfates and absence of benthic fauna indicate increased salinity and intensive evaporation. Additionally, low TOC concentration suggests a low productivity in the basin. On the contrary, stable isotope signals indicate that the sedimentary environment was strongly affected by meteoric water. Moreover, 18O and concentration of Sr suggest that dolostones were formed under the influence of both marine and meteoric waters. Dolomitic mudstones could be deposited in a salt-marsh environment fed by distal sheet floods. Components of palynological material and organic compounds in black dolomitic mudstones indicate the terrestrial origin of organic matter. Dolomitic regoliths were formed as the result of subaerial exposure and karstification of dolostones. Coarse-grained siliciclastics and variegated mudstone are interpreted, respectively, as a fluvial channel and flood plain facies of ephemeric fluvial environment. Sedimentary environment of the Keuper sediments was controlled by two main factors: synsedimentary tectonic movements and climate changes. In the latest Ladinian, the Middle Triassic carbonate platform was emerged, what resulted in the development of palaeosols. Block tectonic movements affected the Tatricum Basin in Keuper time. Horsts were emerged, whereas troughs were filled with fluvial or salt marsh sediments. Intensive tectonic movements are suggested by seismic-generated slumps and abrupt facies changes. More intensive chemical weathering and intensive contribution of pure siliciclastics suggest climate pluvialization in late Ladinian-early Carnian time. On the contrary, domination of physical weathering indicates the aridization of climate in late Carnian?-Norian time. The upper Carnian?-Norian succession was formed in hot and semi-arid climate conditions. Long-term climate changes was masked by short-term climate fluctuations. Geochemical indicators suggest that dolostones represent more humid periods, whereas dolomitic mudstones relatively dry periods.