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The High-Tatric succession of the Tatra Mountains represents the Tatricum domain of the Central Western Carpathians, which in the Jurassic was located on the southern margin of the incipient and expanding Vahic Ocean – a branch of Western Tethys. This paper describes the various depositional consequences of extensional tectonic activity as it impacted on sedimentation in the High-Tatric succession of the Tatra Mountains during the Early and Middle Jurassic. Evidence of such impacts on depositional style and facies development are present within the Dudziniec, Smolegowa and Krupianka formations, in all the High-Tatric tectonic units. These impacts also include erosional surfaces and sedimentary gaps separating particular formations, commonly associated with minor angular unconformities. The Lower Jurassic, pre-Bajocian, Dudziniec Formation of the Kominy Tylkowe (autochthonous) Unit is developed in mixed carbonate-clastic facies. The occurrence and proportion of sand-dominated and carbonate-dominated facies, as well as their thickness differences, were controlled by syndepositional tilt-block tectonics, taking place both in depositional and in neighbouring source areas. The Smolegowa and Krupianka formations (Bajocian–Bathonian) occur in all High-Tatric tectonic units, but in the Czerwone Wierchy and Giewont units they are represented mainly by laterally discontinuous bodies of crinoidal limestone of very limited thickness. The preservation of these deposits only in some areas, as well as their thickness reductions, are effects of differentiated subsidence and uplift of isolated blocks taking place in an extensional regime. Moreover, the Krupianka Formation abounds in condensed facies with ferruginous crusts and stromatolites – a feature characteristic of rapidly drowning ocean margins. Deposits of the Dudziniec, Smolegowa and Krupianka formations are also preserved as infills of extensive systems of neptunian dykes penetrating mainly the Triassic substrate, which is yet another classic symptom of synsedimentary extension. The dominant influence of tectonics on sedimentary development ceased with the onset of deposition of the Raptawicka Turnia Formation in the Callovian.
Calcareous dinocysts and calcitarchs have been investigated for the first time within the Upper Albian limestone and marl succession of the Zabijak Formation from the High-Tatric Unit in the Tatra Mountains (Central Western Carpathians), related to the Oceanic Anoxic Event 1d (OAE 1d). Four groups of morphotaxa of calcareous dinocysts have been distinguished. They totally dominate the assemblages, and belong to the pithonellids. They are represented by Pithonella sphaerica (Kaufmann in Heer) and P. ovalis (Kaufmann in Heer), which dominate, as well as P. trejoi Bonet and P. lamellata Keupp in Keupp and Kienel, which are less abundant. Two other morphotaxa, Colomisphaera gigantea (Borza) and Cadosina oraviensis Borza, occur sporadically in the assemblages. Both forms represent the calcitarch group, which assembled calcispheres of unknown taxonomic affinity. The calcareous dinocyst and calcitarch diversity is low to moderate, compared to the general species richness known from Late Albian assemblages in other Western Tethyan sections. This is interpreted as a result of nutrient input fluctuations due to changes in the circulation pattern of surface and intermediate waters. The changes in the P. sphaerica/P. ovalis ratio along the Upper Albian section are here correlated with short-term (third-order) sea level fluctuations including transgressive and regressive events and a highstand. Pelletization processes might have influenced cyst abundance on the sea floor, especially during periods with oligotrophic surface waters.
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.
Biostratigraphic investigations of carbonate strata that sandwich volcanic rocks and studies of the volcanic rocks were made along five composite lithological sections across the Upper Jurassic-Lower Cretaceous carbonate rocks of autochthonous cover of the High-Tatric Unit in the Osobitá peak area of the Western Tatra Mts. A carbonate microbreccia that consists almost exclusively of limestone clasts containing calpionellids occurs immediately below the volcanics. The youngest identified microfossil Calpionella elliptica Cadisch in the individual limestone clasts showed the age of breccia formation to be younger than late Early-early Middle Berriasian. The volcanic rocks are overlain by the Osobitá Limestone Formation, which in the lowermost horizons consists of a few metres thick crinoidal limestone containing the foraminifers Meandrospira favrei (Charollais, Brönnimann & Zaninetti), Sabaudia minuta Hofker and Montsalevia salevensis (Charollais, Brönnimann & Zaninetti) indicating a Late Valanginian-Early Hauterivian age. The biostratigraphical and sedimentological data obtained show that volcanism took place in several phases. Less intense phases of volcanism are recorded as thin tuffitic laminae within the upper parts of the Tithonian-early Mid Berriasian Sobótka Limestone Member and as fragments of volcanic rock in the carbonate breccia. The main phase(s) of volcanism took place during the Late Berriasian-?Early Valanginian.
Content available Budowa geologiczna doliny Białego Dunajca
The Biały Dunajec Valley is one of the large, meridionally oriented valleys cutting the Podhale Synclinorium. The tectonic origin of this valley has been suggested since the beginning of the 20th century. A large fault zone with an azimuth of about 20° has been recognized here. This zone extends to the north and cuts the Pieniny Klippen Belt, which is significantly lowered in its eastern side. The southern part of the Biały Dunajec fault zone (SBD) extends probably into the Tatra Massif (into the Mała Łąka Valley area and far to the south into the border of the Koszysta elevation and the Goryczkowa depression). The majority of faults constituting the SBD were formed during the initial phase as strike-slip faults; they were reactivated later as dip-slip faults with a prevailing dip-slip, mainly normal component. As a whole, the SBD is a scissor-like fault: in the northern part, near the Szaflary village, downfaulted is its eastern block, whereas in the southern part - its western block.
Tufas in the Podhale Synclinorium (southern Poland) occur as encrustations on moss and plant remains, crusts, porous, clastic and massive tufas. The tufas are almost entirely composed of calcite with small admixture of quartz, illite and chlorite. These deposits indicate the biotic and/or abiotic origin of calcium carbonate. The tufas occur in the vicinity of map-scale and minor fault zones. They precipitate near fissure springs linked with small faults and fault rocks or seepages along them. Exposures with tufas occur along several oblique and lateral zones. The oblique zones are related to Białka and Biały Dunajec faults that have normal components. The lateral zones of tufa occurrences are connected with lateral faults limiting the “zone of beds with gentle dips” and extensional brittle structures within the hinge of the synclinorium. The relationship of the tufa with brittle extensional structures suggests Quaternary tectonic activity of the Podhale Synclinorium that can be explained by continued uplift in the area studied.
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