The research is focused on the feasibility analysis of a numerical model describing the field of strains generated by mining-induced subsidence caused by a deep underground coal extraction, which may contribute to the formation of Earth fissures. The finite elements method and Knothe’s theory were used in the research. The geomechanical modeling was applied for defining zones of strains and maximum horizontal deformations of the terrain. Knothe’s theory was employed for defining boundary conditions of the geomechanical model. The parameters of the empirical and geomechanical models were scaled out on the basis of geodetic surveys in the mining area. The results of geomechanical modeling were compared with the geodetic surveys to select the best model. The presented research confirmed high congruence between the results of modeling with the finite elements method and observations of vertical movements on the surface. The results of modeling also confirmed the assumed highest stress in areas where earth fissures were observed. The proposed solution may be a new research tool applicable to areas where earth fissures potentially occur. and Malinowska Agnieszka A., Misa Rafał, Tajduś Krzysztof.
The deformation measurements are performed for the purpose of obtaining information concerning ground movement and objects on the ground within given time intervals. For the purpose of improving conventional models of deformation analysis (CDA) it is desirable to use several different methods and also implement alternative proce dures as a further improvement, such as the concept of robust geodetic networks and strain analysis, aimed at obtaining objective information about the movements. In the present paper, in addition to the CDA methods, we also analyze the robust methods in deformation detecting and the method of the strain analysis based on elasticity theory as a supplement to the conventional geometric deformation methods (CDA). The mentioned methods are applied and analysed for the case of a test example of Fruška Gora in Serbia, for which there exist geological and geophysical studies of recent tectonic movements. The measuring results for two measuring epochs concern the GNSS vectors measured by applying the fast static method within closed polygons over a ten-year interval, where only the horizontal movement component is analysed. The efficiency of the applied CDA and robust methods is measured by applying a mean success rate (MSR) by applying Monte Carlo simulations in order to investigate the efficiency of a given methods for a given control network., Zoran Sušić, Mehmed Batilović, Toša Ninkov, Vladimir Bulatović, Ivan Aleksić and Gojko Nikolić., and Obsahuje bibliografické odkazy
A refined triple-frequency cycle slip detection and repair algorithm for GPS/BDS undifferenced observables under high ionospheric disturbances is proposed. In this method, three linearindependent optimal observables combinations for GPS/BDS are selected. The residual ionospheric delay estimated from a "calculation-prediction mechanism", namely flexibly determine whether to calculate delay by observables themselves or to predict delay by a feedforward neural network (FNN), is used to compensate for the detection values. Additionally, we devise an adaptive detection threshold based on actual noise level to detect the cycle slip, and adopt the modified least-square decorrelation adjustment (MLAMBDA) to fix integer cycle slip. The performance of the proposed algorithm was tested with observables at 30 s sampling rate in a 2-day geomagnetic storm period. Results showed that the proposed algorithm can detect and repair all kinds of cycle slips as small as one cycle in the case of high ionospheric disturbances. No false repairs are generated despite the occurrence of very few misjudgments., Nijia Qian, Jingxiang Gao, Zengke Li, Fangchao Li and Chen Pan., and Obsahuje bibliografii
by O. Nordgaard. The protist plankton and the diatoms in bottom samples / by E. Jørgensen., KČSN - signatura S-E 128, Poškozené desky., and Desky skenovány z jiné signatury. S-E 128
Four precise leveling campaigns has been carried out in Poland, and for several years there is a functioning system of permanent GNSS stations determining the height of network points. On the basis of these data, several variants of vertical crustal movements models have been developed (Wyrzykowski, 1987; Kowalczyk, 2005; Kontny and Bogusz, 2012). In order to develop a kinematic model of vertical crustal movements, one of the possibilities is an adjustment of the network formed simultaneously with the leveling data and GNSS stations data. The main problem is a need to identify fiducial points between the datasets. This problem can be solved by creation of coherent database containing attributes of both types of data and automatization of the joint point identification process. The article shows the results of such identification process, depending on the amount of data, on the example of the area of Poland. and Bednarczyk Michal, Kowalczyk Kamil, Kowalczyk Anna.
Surface deformation due to underground exploitation affects the safety of overlying structures. Forecasting can predict risks to surface structures and facilitates actions designed to improve their resilience and reduce the potential impact of mining activities. However, forecasting accuracy is limited. Therefore, in practice, model parameters are determined within a certain margin to ensure that critical values of deformation indicators for surface objects are not exceeded. For economic reasons, it is important to minimize these margins while also ensuring that safety is maintained. One important factor influencing forecasting accuracy is the uncertainty in deformation model parameters used for calculations. Therefore, it is critical to adopt an appropriate methodology for determining and addressing the uncertainties in deformation model parameters used in forecasting. This study presents methods for estimating the Knothe's model parameters needed to forecast surface deformation caused by underground mining and defining the uncertainties in those forecasts. Depending on the parameter uncertainties, one of two methods for propagation is proposed: the Monte Carlo method or the law of propagation of uncertainty. Using this approach, it is possible to account for uncertainty and reduce forecast margins. A case study of hard coal mining in the Upper Silesian Coal Basin region of Poland is presented., Wojciech Gruszczyński, Zygmunt Niedojadło and Dawid Mrocheń., and Obsahuje bibliografii
Exhibition of lanthanide tetrad effect in PAAS-normalized REE patterns, and non-CHARAC (non-CHArge-RAdius Control) behavior of Y/Ho and Zr/Hf in limestone of the Ruteh Formation, Kanigorgeh district (NW Iran), were studied in order to understand the reasons of occurrence of lanthanides tetrad effects. The computed values show that the third and fourth tetrads can be used as a good and powerful geochemical tool for investigation of physicochemical conditions of the depositional environment of the limestones. Here, a new mathematical-based method using polar coordination system for tetrad effect values (Tp) was used to evaluate under studying limestone. The correlation between Tp and some geochemical parameters revealed that the limestone was likely deposited under two different conditions. The obtained results indicated that paleo-redox conditions, adsorption and scavenging by kaolinite and metallic oxides, degree of detrital input, diagenesis intensity, and complexation by polycarbonate ligands are likely the main mechanisms for occurrence of tetrad effect phenomenon in REE distribution patterns in the limestone. This means that tetrad effect phenomenon in REE distribution patterns of limestone can be applied as a good geochemical indicator to evaluate the deposition conditions in limestones., Ali Abedini, Mansour Rezaei Azizi and Ali Asghar Calagari., and Obsahuje bibliografii
The aim of the study is to identify the recent local geodynamic processes on the territory of the Dniester PSPP (Ukraine), which arose as a result of the additional man-caused load during the construction of hydro-technical structures. The research is based on the results of 17 cycles of periodic static GNSS campaigns conducted during 2004-2017. In this work the vectors of horizontal displacement of the reference GNSS network points of Dniester PSPP are determined and their scheme is constructed. On the basis of average vectors of horizontal movement velocities during 2004-2017, the value of the velocities of dilatation - the parameter of Earth surface deformation which characterises the relative area expansion or compression, is calculated. As a result of the analysis of velocity distribution of the dilatation of Dniester PSPP territory, the areas of extreme values of compression and stretching are revealed, which testify to the increased geodynamic activity of the pivot part, as well as the main structures of the construction. and Savchyn Ihor, Vaskovets Serhii.
The paper studies the connection between the X-ray and thermo quartz luminescence, the massif formation facie features and differentiation of magmatic melt features, using the example of the Permian-Triassic granitoids from the Kolyvan-Tomsk folded belt (KTFB; the Kolyvan, the Barlak, the Ob, and the Novosibirsk rock massifs). The X-ray luminescence optical spectra and the thermoluminescence curves of quartz from the massifs listed above are obtained. The quartz luminescence is proven to be linked to the features of the magmatic melt differentiation. It is shown that the equivalence of the X-ray- and the thermoluminescence of granitoids quartz from different massifs are the result of similar conditions and mechanisms of the granitoids formation with close establishment periods. The obtained data make it possible to consider the KTFB granitoid magmatism as a result of natural magmatic differentiation of the original magma and to use the quartz emission spectra for typing granitoid massifs. The individuality of the Novosibirsk massif quartz, manifested in intense luminescence of Fe 3+, defects of O * (370 nm) and thermoluminescence (TL) at 180-220 °C, can be associated with high fugacity of oxygen, increased temperature and rate of mineral formation in rock collapse mode under tectonically active zone conditions. At the same time, the obtained data provides evidence for the differences in the leucocratic magmatism of the area, allowing differentiation of the Kolyvan-Tomsk folded belt leucogranites into the leucogranites of the Novosibirsk massif (Mo-W type of mineralization) and the leucogranites of the Kolyvan and the Barlak massifs characterized by rare metal mineralization (stannic-tungstic-beryllic with silver). and Boroznovskaya Nina Nikolayevna, Nebera Tatyana Stepanovna.
Resonance frequencies of unconsolidated sediments of the Iška alluvial fan (Ljubljana Moor basin) were derived using microtremor method. Free-field measurements were conducted in a grid with point spacing of approximately 250 m. The sediments frequency-thickness relationship, h = 202.97 f -1.139, was obtained on the basis of 107 microtremor measurements, six existing boreholes that reached the Pre-Quaternary basement and two seismic reflection profiles. The reliance of the obtained relationship was evaluated with the R2 coefficient, which shows a very good level of determination. The resonance frequency map reveals the existence of an N-S oriented deeper buried valley (maximum depth 119 m) in the Western part of the alluvial fan. The microtremor HVSR amplitude map does not show any specific spatial distribution pattern, with the exception of a relatively narrow band of low amplitudes located north of Iška vas. This is probably related to an area of severely fractured bedrock along the Mišji Dol fault. Map of the Quaternary sediment thickness and map of the Pre-Quaternary basement topography were constructed on the basis of the established relationship. The basement topography map shows rather steep western slopes of the buried valley down to deepest part, followed by a gradually ascending basement towards the Eastern part of the fan. The comparison of the obtained parameters a and b in frequency-thickness relationship with other sedimentary basins around the world reveals a small variation of b values, and a rather large range of a values, which implies that the parameter a is characteristic for certain geological areas. The results of this research will find use in constructing more accurate hydrogeological models and for assessment of possible sediments-structure resonance effects in seismic microzonation., Lovro Rupar and Andrej Gosar., and Obsahuje bibliografii