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1

Interaction between tectonics, plutonism and mineralization of the Duna Pb-Ba ore deposit regarding fluid inclusion study (Central Alborz, Iran)

Sadeghi Alireza, Asiabar Saeid Hakimi, Nezafati Nima, Ganji Alireza, Mukherjee Soumyajit

Acta Geologica Polonica

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2023

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Vol. 73, no. 2

201--222

EN

This article discusses the impacts of overprinting of tectonic and plutonic events on the mineralization of the Duna Pb-Ba ore deposit, according to geologic settings and fluid inclusion studies. The Duna carbonate-hosted deposit contains a significant amount of Ag (18.9–264.3 ppm ), Cu (77–41600 ppm), Sb (32.7–11000 ppm), Sr (63.5–15100 ppm), and Fluid inclusions with 7.34–23.65 wt.% NaCl equivalent. The homogenization temperature of about 110–285°C, as well as the paragenesis of the minerals shows a difference compared with other Pb-Zn deposits such as the Irish-type and MVT. The ore mineralization in the Duna mine occurred as stratabound, open space-filling, and along the brecciated fault zones. The concordant (stratabound) type of mineralization, with salinity and homogenization temperature of 18.54 to 23.65 wt.% NaCl equivalent, and 113°C to 165°C respectively, is usually typical of MVT-ore deposits, which in this area evolved during the Early Cimmerian orogeny and was later interrupted by mineralization along younger brecciated fault zones with salinity and homogenization temperature of 7.34 to 23.65 wt.% NaCl equivalent, and 113°C to 285°C respectively. This discordant mineralization, which occurred along the faults, formed by the end of the Late Cretaceous and during the Cenozoic as a result of the intrusion of a plutonic mass, and is comparable to the Irish-type ore deposits.

2

Sound Transmission Through a Thin Plate with Shaped Frequency Response

Wrona Stanislaw, Mazur Krzysztof, Rzepecki Jaroslaw, Chraponska Anna, Pawelczyk Marek

Archives of Acoustics

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2019

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Vol. 44, No. 4

731--738

EN

Thin plates, in the form of individual panels or whole device casings, often separate the noise source from its recipients. It would be very desirable if the panels could effectively block the sound transmission preventing noise from further propagation. This is especially challenging to achieve at low frequencies. A promising approach, intensively developed in the recent years, is to employ active control methods by adding sensors and actuators, and running a control algorithm. However, if the noise is narrow-band, an alternative passive solution originally developed by the authors can be applied. It is based on appropriately located passive elements which can be used to alter the frequency response of the vibrating structure thus improving its sound insulation properties. Such an approach is referred to as the frequency response shaping method. The purpose of this paper is to further develop this method and apply it to a device casing panel. The efficiency of the method is evaluated by simulation and real experiments. Appropriate cost functions and mathematical models are formulated and used to optimise the arrangement of passive elements mounted to the plate, enhancing its sound insulation properties at the given frequency range. The results are reported, and advantages and limits of the method are pointed out and discussed.

3

Dynamic behavior of steel frames with tuned mass dampers

Jouneghani K. T., Hosseini M., Rohanimanesh M. S., Dehkordi M. R.

Advances in Science and Technology. Research Journal

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2017

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Vol. 11, no 2

146--158

EN

In this paper, the application of tuned mass damper in improving the response of structures is considered. At first, three frames of 3, 9 and 20 stories are evaluated in which time history analysis is done according to El – Straw earthquake. The maximum reduction of among the three mentioned frames belongs to a 20-stories structure in which the rate of story displacement reduction is between 25 to 45%, and this indicates that by increasing the height of the structure, the performance of tuned mass damper improved. In the second part, the effect of semi-active tuned mass damper is studied on a 10-stories frame. Studies showed that using a tuned mass damper system with viscous damper with controller force decreases the average of maximum displacement of roof story down to 39.9 % and this amount of reduction is 22.8% for semi-active tuned mass damper. Finally, the performance of tuned Single and multiple mass Damper is evaluated on a 20-stories frame, and the results show that single and multiple dampers decrease structures ‘responses and the performance of tuned multiple dampers depends on the mass and frequency ratio and also concluded that the performance of tuned multiple mass dampers is reduced by transition to middle of the structure stories.

4

On possible applications of smart structures controlled by self-stress

Gilewski W., Al Sabouni-Zawadzka A.

Archives of Civil and Mechanical Engineering

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2015

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Vol. 15, no. 2

469--478

EN

Civil Engineering (CE) is one of the many fields of possible implementation of smart or intelligent technologies. The present paper is an attempt to specify and estimate problems and areas of CE suitable for the application of such technologies, with the focus on Bridge Engineering (BE). Precise definitions, explanations and classifications of terms used in smart technique are introduced and components of smart systems are defined. Analogies between smart systems and biological ones are indicated. The paper presents some of the research projects carried out in the field of CE, according to the current state-of-the-art. Concepts of smart bridges are proposed and several examples of structural control performed on space trusses and tensegrity structures with self-stress are introduced. Examples of structural control presented in the paper show that characteristic displacements of the analysed structures may be reduced by changing the prestressing force applied to the single modules, which are a part of the structure. Results of the performed analysis indicate that tensegrity structures are much more prone to the changes in the value of prestressing force than truss structures, which makes them a promising solution as far as structural control is concerned.

5

Strukturalne uwarunkowania rozwoju rzeźby Karpat zewnętrznych : nowe spojrzenie

Jankowski L., Margielewski W.

Przegląd Geologiczny

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2014

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Vol. 62, nr 1

29–-35

EN

The article presents a new concept of structural control on the Outer Carpathians relief. The Carpathians’ relief development originated in the stage of sedimentary basin deposition (e.g., gravitational positioning of fragments of rock massif), as well as in the compressional stage of the orogen formation, and, finally, in the stage of secondary tectonic deformation, such as: strike-slip faulting, radial extension, and great extensional collapse of the Carpathian massifs. The difference in elevation between the Beskidy Mts. and Carpathian Foothills belt is caused by the structural position of these segments of rock massifs within an accretionary prism formed during the compressional stage. The tectonic elements formed during the earliest stage of compression (Magura, Dukla and southern Silesian units forming the High Beskid zone) attain the highest structural and elevation position, whereas the elements included as the last ones to the accretionary prism (Sub-Silesian and Skole units) take a lower topographic position, forming the foothills belt. A concept that gravitational collapse generated back-thrusts and tectonic exhumation of the Carpathian massifs allows us to explain seemingly considerable erosional unroofing of the Carpathian surface, estimated at several kilometres. Alternating position of elevated and lowered mountain ridges (Bieszczady–Beskid Niski–Beskid Wyspowy–Beskid Makowski Mts.) can be explained by their association with a major strike-slip fault. Chaotic complexes frequently occurring in the Carpathians are very important for the relief transformation and development of river network (controlled not only by dislocations, but also by chaotic complexes), as well as for the presence of erosional remnants (isolated hills representing blocks in matrix).

6

The structural control of the Mroczna Cave development on the slopes of Mt Kornuty (the Flysch Carpathians, Beskid Niski Mts)

Zatorski M.

Landform Analysis

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2014

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Vol. 27

55--65

EN

The Mroczna Cave is one of the longest caves in the Beskid Niski Mts., located on the south-western slopes of Mt Kornuty, along the main scarp of the landslide. According to the geomechanical criterion, it is dilation cave, where extension has played a major role. Morphotectonic analysis indicates that the main gravitational movement was of a toppling nature but there were also rotation around the vertical axis as well as a backward rotation. The relatively large cave depth (15.5 m) and its shape (cross-section of its passages) indicate that it was formed along a new gravitational cutting surface of the rock massif, associated with joint sets.

7

On the semi-active control of carrying structures under a moving load

Pisarski D., Bajer C. I.

Vibrations in Physical Systems

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2010

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Vol. 24

325--330

EN

In this paper we address a group of recent research focused on the semi active control problems in carrying structures systems subjected to a travelling load. The magnitude of the moving force is assumed to be constant by neglecting inertial forces. The response of the system is solved in modal space. The optimal control problem is stated and it is solved by using of Pontryagin Maximum Principle. Switching control method is verified by numerical examples. The controlled system widely outperforms passive solutions. Due to its simplicity in practical design, the presented solution should be interesting to engineers.

PL

W pracy przedstawiono wyniki badań półaktywnego sterowania w układach nośnych poddanym obciążeniom ruchomym. Obciążenie zostało przedstawione jako bezinercyjne. Odpowiedź układu została wyznaczona w reprezentacji modalnej. Sformułowano zadanie sterowania optymalnego. Uzasadniono zastosowanie sterowań typu bang-bang opierając się na Twierdzeniu o Maksimum Pontryagina. Proponowana metoda sterowania została zweryfikowana na podstawie przykładów numerycznych. Wykazano przewagę układów sterowanych nad układami tłumienia pasywnego. Opracowana strategia sterowania jest prosta w implementacji i może być atrakcyjnym rozwiązaniem dla inżynierów.

8

Typy przemieszczeń grawitacyjnych mas skalnych w obrębie form osuwiskowych polskich Karpat fliszowych

Margielewski W.

Przegląd Geologiczny

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2004

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Vol. 52, nr 7

603-–614

EN

Patterns of gravitational movements in the Flysch Carpathians are connected with tectonic and lithologic anisotropy of the rock massifs. The paper reviews the baisic patterns of mass movemets in the Flysch Carpathians: toppling, translational, rotational and compound sliding, sagging and complex type of mass movement, ilustrated by selected forms using the structural (joints, faults) analysis. Toppling in the Carpathians is typical for double ridge and top trenches (example: Gaworzyna double ridge in the Beskid Sądecki Mts). Translational landslides with flat, „structural” sliding surface typical for shallow forms, might form along the bedding plane (example: Duszatyn and Prełuki landslides,Western Bieszczady Mts), as well as along the joints an fault surface. The classification of ”structural landslides” commonly used nowadays, pertains only to translational landslides. In deep-seated landslides the shearing zone will be combined, composed of structural sections (joints, faults, bedding plane) and shearing elements. Thus, to majority Carpathians landslides develop as mixed type (non circular) grouping complex movement, involving of various types of displacement: rotational–translational–toppling. Purely rotational movements with circular failure are developed in the Carpathians flysch massifs, when thick bedded sandstoned (resistant) are underlain by soft shales (example: pure rotational lndslide in Mt Kostrza in Beskid Wyspowy Mts). Influence of anisotropy of these rocks on sliding surface is strong by reduced, and soft rock favours rock flow (sagging) development, usually transformed later in to a rotational type of movement (example: rotational landslide with toppling and sagging elements on Mt Muronka. in Beskid Śląski Mts). Very interesting mixed landslide on Mt Luboń Wielki (Beskid Wyspowy Mts) represents alistric (antithetic) type of landslide.

9

Jaskinia szczelinowa Diabla Dziura w Bukowcu [Pogórze Rożnowskie, Karpaty zewnętrzne] jako inicjalne

Margielewski W., Urban J.

Przegląd Geologiczny

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2004

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Vol. 52, nr 12

1171--1178

EN

Diabla Dziura cave-the deepest pseudokarst cave (42 m) of the Polish Outer Carpathians (Rożnów Foothill) represents a tension crack of the initial stage of landslide development. Several types of gravitational movements - spreading, toppling, rotational - have been observed in the cave. They will gradually evolve into a landslide. The joints system of the cave is featured by zonality. All joint sets (L, T, D1, D2) occurring in the massif are present in the complete relaxed, upper part of the massif (to the depth 10-12 m), whereas the set D2, parallel to the mountain ridge stretching, predominates in the deeper part. To the depth 25 m the joint surfaces are often slightly curved, deeper they are straight and even. The main passages of the cave represent polygenetic joints, developed due to tensional stresses operating within the ridge. Curved shape of the joint surfaces is an effect of correlation between foundations of jointing (combination of tectonic and denudational-unloading stresses) and a way of their opening, generated partly by tectonical extension, partly by denudational factors in the upper part of the ridge. Also the lithological character of the rock massif (thick-bedded sandstone) could play a significant role in formation of these curved surfaces.

10

Geological control on the Osława River meander at Duszatyn, Western Bieszczady Mountains, Polish Outer Carpathians

Margielewski W.

Annales Societatis Geologorum Poloniae

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2004

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Vol. 74, No 3

325-338

EN

At Duszatyn village (Western Bieszczady Mts.), the Osława River forms an unique meander loop which is not typical for the mountainous area. Detailed analysis has shown that this landform was created due to the evolution of two left-hand tributaries of the Osława River during the formation of its regressive water-gap. These processes were determined by mass movements which have strongly stimulated the fluvial system. The origin of the Osława River meander was largely controlled by lithological differences in rock resistance, orientation of the joint pattern, as well as the presence of bordering oblique and thrust faults which have had a bearing on the diversified neotectonic uplift of the area.