Geodetic geodynamic studies were conducted in the Wrocław Plain, situated in the SE part of the Central European Subsidence Zone (CESZ). The boundaries of this plain coincide with the outline of the rhomboidal Cainozoic Wrocław Basin. This area has been chosen for detailed examination taking into account the results of previous geodynamic research, pointing to constant subsidence of the Wrocław region. Analysis of drainage network and changeable thicknesses of the Neogene an d Quaternary strata also indicates weak, although stable subsidence of the central part of the Silesian Lowland and relative, small-scale uplift of the Fore-Sudetic region situated in thes outh and an area placed north of the Odra River valley. The studies consisted in measuring elevation changes of benchmarks along lines of precise levelling during 1956-1999 period, establishing a GPS network points, as well as measuring and processing of GPS data acquired during 2008-2010 time span. Displacements of benchmarks of precise levelling lines point to block-type mobility of structures located in the SE part of the CESZ, while GPS measurements indicate deformations related to bending of the Cainozoic sedimentary cover underlain by metamorphic bedrock and Permo-Mesozoic strata. Three years of observations enable us to distinguish two zones typified by compressive deformations being coincident with subsiding areas. One of these zones strikes NW-SE and marks the CESZ axis, the second one, oriented NNW-SSE, fo llows the orientation of a deeply buried Carboniferous-Permian tectonic graben (the Eastern Fore-Sudetic Basin) and a much shallower trough filled with Cretaceous strata in the Opole region. Uplift typifies the Fore-Sudetic Block as well as areas situated close to Opole town and north of the Odra River valley., Piotr Grzempowski, Janusz Badura, Stefan Cacoń, Jan Kapłon, Witold Rohm and Bogusław Przybylski., and Obsahuje bibliografické odkazy
Geological structure, including main faults and faults zones, of the Góry Stołowe National Park originated in Neogene. Displacements on faults in the Poříčí-Hronov and the Czerwona Woda fault zones have been revealed at present times. A network of 11 research points was established to register this process and phenomena associated with it. The first measurement, consisting of GPS and gravimetric observations, was performed in 2008. It has been complemented with relative measurements of the faults in selected places where crack-gauges have been installed. Accuracies of the first GPS measurements indicate ability to detect horizontal movements with accuracy of several millimetres., Stefan Cacoń, Jurand Wojewoda and Jan Kapłon., and Obsahuje bibliografii
In the contribution geological structure and geophysical data along the northern part of the Diendorf-Čebín tectonic zone (DCTZ) is analyzed in relation to the position of the measured GPS test areas and precise levelling profiles. For this purposes the former geophysical data have been reambulated and analyzed, too. Revision of geological knowledge and sources has been done in places of the proposed polygons. The results of reinterpretation of the Grav/Mag data and selected seismic reflection profiles suggest new possibilities and variety of structural interpretations of this tectonic zone. It is evident that the whole tectonic system has undergone complicated tectonic development during the Paleogene and Neogene. Therefore the recent mapping and analyses by GPS and precise levelling have to be realized in places where the geological structural ambiguity has to be eliminated., Lubomil Pospíšil, Otakar Švábenský, Josef Weigel and Michal Witiska., and Obsahuje bibliografii
To investigate the geodynamic pattern of the Bohemian Massif in Central Europe, the GEONAS network of permanent GNSS stations was established. It now consists of 18 stations, recorded both the NAVSTAR and GLONASS positional signals; they are located along the tectonic zones of the Massif in order to monitor any movement activities. Yet other stations are still planned to be built, and some recent stations are to be moved within these active areas to increase their local distribution density. The GNSS data are processed by the use of Bernese GPS software 5.0. The time series of station positions give fundamental information for both regional and local geodynamic studies. The GEONAS network covers an area of 400 by 220 km, and it allows the effects of dynamic processes going on inside the Earth’s crust, as well as the upper lithosphere to be monitored. A few examples of geodynamic interpretations are presented here., Vladimír Schenk, Zdeňka Schenková, Milada Cajthamlová and Zdeněk Fučík., and Obsahuje bibliografii
Since 2002, the US-German GRACE (Gravity Recovery and Climate Experiment) mission has been providing a precise survey of the Earth's time-variable gravity field, with unprecedented temporal and spatial sampling. GRACE time-variable gravity fields provide a means of measuring the temporal and spatial variations of mass redistribution within the Earth system. The GRACE mission has started a new era in studying a series of geophysical problems ranging from deep Earth structure to tracking mass redistribution on and near the surface of the Earth. Time variability of the gravity field presented here is based on the transformation of “monthly gravity field models” to the geoid. We show the changes caused by the global water cycle and land hydrology., Jan Kostelecký, Aleš Bezděk and Jaroslav Klokočník., and Obsahuje bibliografii
a1_The aim of this paper is to present the strategy of determination of the reference solution for the ASG-EUPOS (Active Geodetic Network - European Position Determination System) coordinate monitoring system. ASG-EUPOS is a network of permanent GNSS (Global Navigation Satellite System) stations controlled by the Polish Head Office of Geodesy and Cartography (HOGC), which main role is to realize the ETRS89 (European Terrestrial Reference System) in the territory of Poland. The Centre of Applied Geomatics (CAG) of the Military University of Technology (MUT) performs a control processing of the network and it is the leader of the ASG+ (the supporting modules for ASG-EUPOS system real-time services) project within which the coordinate monitoring system was developed. The coordinate monitoring is aimed to assess the actual performance of the GNSS stations and the reliability of the system and its services. The Polish realization of the ETRS89 is also controlled, where the deviation of the actual coordinates from the reference values are monitored. Furthermore, the monitoring enables the analysis of factors that degrade the individual GNSS stations and assess the solution stability which has impact on the quality of the determined geodynamic parameters. The reference solutions (coordinates and their changes over time) were determined according to the recommendations of the IAG sub-commission for the European Reference Frame concerning densification of EUREF. The paper presents the determination of the reference cumulative solution and the results of the processing of a few years long series of GNSS observations. The analysis are performed by the Bernese 5.0 and CATREF software. The results consists of daily and subdaily ASG-EUPOS reference solutions. They are also considered as input data for geodynamic studies to determine the horizontal and vertical velocity fields., a2_Estimation of the individual station velocities is of crucial importance for the ETRF (European Terrestrial Reference Frame) reference frame maintenance to assess the compatibility of the current station position with its catalogue (reference) value and apply coordinate correction if necessary., Karolina Szafranek, Janusz Bogusz and Mariusz Figurski., and Obsahuje bibliografii
The Geodynamic Network Sudety was joined to the Czech Gravity Reference Network (CGRN) by two weeks of the relative gravity measurements. The gravity stations of the CGRN were used as the anchor stations. There were used two relative gravimeters LaCoste & Romberg G. The method of measurement, used instruments, mathematical processing, variants of result computations and their accuracy are discussed., Petr Lukavec and Martin Lederer., and Obsahuje bibliografii
During 2007 and 2008 there were realized gravity measurements using the relative gravimeter Scintrex CG-5 on sites of geodynamic networks HIGHLANDS and fundamental gravity sites of the Czech Gravity Reference Network. The gravity measurements were concentrated on monitoring the long-term trends of gravity acceleration changes among individual measurement sites. The methodology of measurement was optimized and preliminary time changes in gravity differences among sites were determined., Roman Kujal, Vladimír Schenk and Zdeňka Schenková., and Obsahuje bibliografii
The GRID_STRAIN software that runs under the MATLAB® environment helped us in achieving the continuous strain field model. Unfortunately, the program averages the results. Therefore, the authors’ main goal of this paper was to work out a method of good verification of data to avoid falsifying of the results of strain calculations. We decided to use the method of the Delaunay triangulation to build a set of triangles of the data (EPN and ASG-EUPOS stations as the vertexes) and by the use of the velocities of each point and their errors, to estimate the single strain in each triangle. This approach made it possible to exclude the outlying values from the data. Selection of the criteria of the characteristic of insufficiently stable points in order to remove them from further computations is of a great importance for the final results of computations of the deformation field. In such a tectonically stable region, as the area of Poland, the strain values should not be higher than 3 to 4 nanostrains/year. At the low rate of tectonic deformations observed in Poland, the disturbances resulting from insufficient stabilization of the ASG-EUPOS network influence the computations of the deformation field to a significant extent. Improper stabilization of a single permanent station causes unification of the deformation field within 2 to 3 computation triangles having a common vertex at this station. Based on this assumption, nearly 30 of the ASG-EUPOS stations were excluded from further strain calculations. The analysis of the geodynamic consistency of the deformation field for the computation triangles is basis for indicating stations for which the dislocation resulting from insufficient stabilization, significantly exceeds the dislocation resulting from the deformation of the lithosphere. Most of the ASG-EUPOS network stations may be used for analysis of local differentiation of the deformation field in Poland., The regularities of the deformations distribution determined by ASG-EUPOS network stations constitute a new set of data which will be used for further geodynamic interpretation. In case of lower rank disturbances resulting from destabilization of the network stations, this factor’s component cannot be recognized using qualitative analysis of the deformation field., Janusz Bogusz, Anna Klos, Mariusz Figurski, Marek Jarosinski and Bernard Kontny., and Obsahuje bibliografii
This paper shows how the local effects can change the value of maximum accelerations from mining-induced tremors. The analysis was carried out basing on data collected from acceleration stations installed in Bytom Syncline region (Upper Silesia). The estimation of the local effects was obtained on the basis of deviations from the attenuation relation. The accelerograms were recorded from the mining tremors in low seismic energy range and in epicentral distances in the range from 500m to 5000m. The obtained re sults were correlated with results from Horiz ontal to Vertical Spectral Ratio (HVSR) technique. This method is based on simple theoretical founda tion and is commonly used in natural seismicity studies. Our results show that the H/V ratio technique gives a reasonable estimate of the surface amplification for frequency range between about 2 and 8 Hz. In case of simple geology and when the signal to noise is adequately high the results are the best. All the results show that there occur local effects., Adam Fref and Wacław Marian Zuberek., and Obsahuje bibliografické odkazy