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Analysis of the trace fossils from Paleogene formations of the Central Western Carpathian (Orava region)

Simo V., Starek D.

Geology, Geophysics and Environment

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2016

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Vol. 42, no. 1

126

EN

Up to now only little attention was dedicated to the study of the trace fossils in the development of the Central Carpathian Paleogene Basin in the Orava region. Occasional trace fossils findings from the Central Carpathian Paleogene formations in the Orava and others regions were referred by Plička (1987). Other specialized works on trace fossils from these formations from the Orava region were not published. Study of trace fossils is strongly influenced by the existence of well exposed outcrops within individual formations. The best exposed outcrops are situated in the basal Borové Formation as well as in the higher parts of Paleogene sequences – mainly in the Zuberec Formation. This preliminary study shows a relatively rich diversity of trace fossils associations across the Central Carpathian Paleogene Basin. We present new finds of trace fossils, within which we have classified 7 ichnogenera, 11 ichnospecies and 2 types of trace fossils, which were not closely systematically classified. Many trace fossils identified in the Orava region are typical for some palaeoenvironments, which are characterized by a specific lithology, nature of the substrate, dynamics of the environment, amount of nutrients and stability or fluctuations of oxygen in the bottom waters. The trace fossils assemblages reflect changes of depositional systems during the tectonic and sequence stratigraphic development of the basin. Early Eocene shallow-sea environment of the Borové Formation including the rocky coast, sandy dynamic littoral, transition - al and internal shelf zones are characterized by findings of traces of Entobia, Gastrochaenolites, Nummipera, Ophiomorpha and Skolithos. On the contrary, a significant deepening of the deposition environment during the Oligocene, documented by turbidite sedimentation of Zuberec and Biely Potok formations is characterised by findings of graphoglyptids ( Spirorhaphe, Nereites, Paleodiction, Protopaleodictyon, Megagrapton ) or traces of deposit feeders ( Arthrophycus, Chondrites, Planolites, Phycodes, Scolicia, Zoophycos).

2

Eustatic and tectonic control on late Eocene fan delta development (Orava Basin, Central Western Carpathians)

Starek D., Sliva L’., Vojtko R.

Geological Quarterly

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2012

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Vol. 56, No 1

67-84

EN

The evolution of the Central Carpathian Paleogene Basin (CCPB) reflects an important role of relative sea level changes on a tectonically active basin margin. After the initial upper Lutetian/Bartonian transgression, the next regressive-transgressive cycle played a key role in a formation of the late Eocene fan delta facies associations in the southern Orava region of Northern Slovakia. Detailed sedimentary analysis allowed the separation of the following three facies associations which represent distinct depositional environments: alluvial fan (subaerial fan delta; Unit 1); subaqueous fan delta (Unit 2); and prodelta/slope and basin (Unit 3). The first stage of delta development is connected with eustatic sea level fall at the Bartonian/Priabonian boundary, accompanied by subaerial exposure, fluvial incision and deposition of alluvial fan sediments. Subaerial deposition was characterized by a variety of mass flow conglomerates with a red muddy matrix, interfingering with stream or sheetflood deposits. The next stage of the delta corresponds to high-amplitude transgression related to rapid tectonic subsidence along the CCPB margins during the Priabonian. The vertical arrangement of facies suggests retrograde delta development that shows rapid submergence of the subaerial parts and onlap of subaqueous mass flow conglomerates, often reworked by waves or wave-induced shallow-marine currents. Continuous deepening of the depositional environment during the late Priabonian/early Rupelian led to the relatively rapid superposition of prodelta/slope and basin facies associations by slowly accumulated hemipelagic deposis.

3

Suppression of vibration with optimal actuators and sensors placement

Starek L., Starek D., Solek P., Starekova A.

Archives of Control Sciences

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2010

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Vol. 20, no. 1

99-120

EN

It is proposed to place the actuators to maximize the mean value of energy transmitted from or dissipated by the actuators, while the sensor location should maximize the mean square value of system output, which also maximizes the signal-to-noise ratio. By using explicit expressions for controllability and observability grammians as well as modal energies, it is shown that the approaches based on the system responses to transient and persistent disturbances are closely related, and are equivalent for structures which damping is small and the natural frequencies of which are well spaced. The method of actuator and sensor optimal location via grammians was proposed and compared it with results given by the method of matrix norms.

4

Late Eocene to Quaternary deformation and stress field evolution of the Orava region (Western Carpathians)

Peskova I., Vojtko R., Starek D., Sliva L.

Acta Geologica Polonica

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2009

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Vol. 59, no. 1

73-91

EN

The northern part of theWestern Carpathians suffered polyphase deformation at the boundary between their Central and Outer parts. Palaeostress analysis in the Orava region revealed the existence of five different stress fields in the period from the Late Eocene to the Quaternary. The evolution of the stress fields was determined by detailed structural analysis of the fault slip and fold orientation data. The orientation of the stress fields shows an apparent clockwise rotation from the Late Eocene to the Quaternary. During the Late Eocene to Oligocene, E-W compression and perpendicular tension affected this area. This was the time when the Central Carpathian Palaeogene Basin formed. After this compression, the palaeostress field rotated approximatly 40-50[degrees], and NW-SE compression and NE-SW tension took place in the Early Miocene. The Middle Miocene to Pliocene was characterised by progressive rotation of the palaeostress field from NW-SE to the NE-SW direction of the maximum principal compressional stress axis ([sigma][1]). This clockwise rotation of the Oligocene to Quaternary palaeostress fields here is explained by the effect of the counterclockwise rotation of the ALCAPA microplate, and by the regional stress field changes in this region. The Quaternary stress field was reconstructed on the basis of structural measurements in the Pliocene sedimentary formations of the Orava-Nowy Targ Basin. The results of the palaeostress analysis show that the Quaternary stress field is characterised by E-W-oriented S[h] (minimum horizontal compression) and N-S-oriented S[H] (maximum horizontal compression).

5

Suppression of vibration of a clamped beam via piezoceramics

Starek L., Solek P., Starek D., Starekova A., Blesak P.

Mechanics / AGH University of Science and Technology

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2007

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Vol. 26, no. 4

187-194

EN

Contribution deals with the suppression of the resonance vibration of a clamped beam with sensors and actuators made of piezoceramics material. It will be discussed the problem of influencing of a response of vibration by higher frequencies so called control and observation spillover. The model of a beam with piesoceramics was designed in environment ANSYS. The properties of the model have been identified from the response on an unit step impuls (voltage). The control was realized by controller with PPF method. Simulation of control has been realized on the clamped beam in environment MATLAB. There was designed an experimental test bed for verification of the simulation results.

PL

Artykuł dotyczy tłumienia drgań rezonansowych jednostronnie zamocowanej belki z czujnikiem i aktuatorem wykonamym z materiału piezoelektrycznego. Omówiono problem wpływu odpowiedzi w postaci drgań o częstotliwościach większych od częstotliwości Nyquista na sterowanie i sprzężenie zwrotne, nazywanego w literaturze angielskiej: control and observation spillover. Model belki z piezoelektrykiem został zaimplementowany w programie ANSYS. Właściwości modelu zostały zidentyfikowane na podstawie odpowiedzi układu na wymuszenie w postaci skoku jednostkowego (skoku napięcia). Sterowanie układem zostało zrealizowane przy wykorzystaniu regulatora z dodatnim sprzężeniem zwrotnym od przemieszczenia. Symulacja sterowania jednostronnie zamocowanej belki zrealizowana została w środowisku MATLAB. Zaprojektowano również eksperymentalne stanowisko badawcze do weryfikacji badań symulacyjnych.

6

Palaeoclimatic implications across the Eocene-Oligocene transition in the Central Carpathian Palaeogene Basin: demise of carbonate platform and cool-water influx

Sotak J., Starek D., Banska M., Biron A., Kotulova J.

Biuletyn Państwowego Instytutu Geologicznego

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2001

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nr 396

142-143