This paper presents examples of application of the method of local quasigeoid modelling based on the geophysical technique of gravity data inversion, using non-reduced surface gravity data and GNSS/levelling height anomalies. Its capacity is demonstrated with three examples consisting in computing detailed local quasigeoid models for three areas situated in Poland. The test areas are different in size (3,900, 23,000, 117,000 sq. kilometres), in geographic location as well as in density of the gravity data coverage. For each of the test regions, calculations were done in three variants, viz. without using any global geopotential model and with application of EGM96 and EGM08 models. The obtained results indicate that the applied method is suitable for creating high accuracy local quasigeoid models (the accuracies obtained were at the level of accuracy of GNSS/levelling test data)., Marek Trojanowicz., and Obsahuje bibliografii
The paper presents analysis relating to the method of local quasigeoid modelling based on the geophysical technique of gravity data inversion, using non-reduced surface gravity data and GNSS/levelling height anomalies. One of the main problems occurring in the application of the method is to determine the model weighting matrix, the purpose of which is to control the inversion process. This paper presents the analyses concerning the determination of certain constant coefficients signed as, and, appearing in the definition of the model weighting matrix. The calculations performed indicate that because of the accuracy of the density model, the coefficient should be in the range of 01. 0 001. 0, and the range 005.00025.0 should be adopted as the optimal. As the optimal values of the coefficients and, values 1.0 and 01.0, for the zones of constant density with area less than about 130 km2 were determined., Marek Trojanowicz., and Obsahuje bibliografické odkazy
In the article the results of repeated satellite positional measurements of station VYHL of the Sněžník Network over period 1994-2006 are presented. Altogether 17 Brno University of Technology measuring campaigns were carried out and evaluated. The observation data (acquired mostly with Leica GPS receivers) were processed with the scientific Bernese GPS Software and the commercial Leica SKI-Pro software packets. Unified procedure for campaign data processing including the alignement of the resulting positions to respective EUREF Permanent Network weekly solutions had been adopted. Only the stability in horizontal direction was analysed. Positional stability of the VYHL station was considered in respect to the surrounding IGS, EPN, and local stations which were used for a local reference frame definitions, at three different levels. First level information was obtained from relations to surrounding stations of the Sněžník Network in distances up to 10 km, second level represent the relations to nearest EPN stations in distances about 100 km, and finally third level represent the relations to surrounding IGS Network stations in distances about 300 - 400 km. Another approach to VYHL stability assessment was the an alysis of slope distances time series from VYHL to neighbouring GPS stations. Outlined are also possibilities of exploitation of the recently completed CZEPOS Network., Otakar Švábenský and Josef Weigel., and Obsahuje bibliografické odkazy
The technique of assessing the failure of rigid overlying strata is applicable to deep mining with thick coal seams (a thickness of more than 1 m in the Ostrava-Karvina Coalfield), and in one case to longwall mining with controlled caving. The assessment of failure of rigid overlying strata makes it possible to distinguish whether the rigid overlying strata of rocks has been deformed or whether a strutting arch has been formed over the goaf below which is an area that is free from stress. Good knowledge of the mining, technical and geological conditions of a given site is a prerequisite for successful evaluation. There are advantages to utilising surface measurements for interpreting the effects of changes in rock mass, especially in areas of high overlying strata. The practical importance of failure assessment of overlying strata consists in determining the size of the mined-out area where the deformation of the rigid overlying strata occurred, which is dependent on the character of the rock mass. This paper is set in the context of the expected width of the goaf during deformation of rigid overlying strata within parameters that describe the mining and geological conditions of the locality. Changes in the area of the goaf, based the results of tensometric measurements, will also be placed in context., Eva Jiránková, Lubomír Staš, Vlastimil Kajzar and Hana Doležalová., and Obsahuje bibliografii
The paper presents a computer module for GPS slant delay determination using data from COAMPS (Coupled Ocean/Atmosphere Mesoscale Prediction System) mesoscale non-hydrostatic model of the atmosphere which is run on IA64 Feniks computer cluster in the Department of Civil Engineering and Geodesy of the Military University of Technology. The slant delay is the result of integrating the ray (eikonal) equation for the spatial function of tropospheric refraction along the GPS wave propagation path. The work is a phase of research concerning operational methods of GPS slant delay determination using data from mesoscale non-hydrostatic models of the atmosphere, like COAMPS of the Naval Research Laboratory (NRL) and the Weather Research and Forecasting (WRF)., Mariusz Figurski, Marcin Gałuszkiewicz, Paweł Kamiński and Krzysztof Kroszczński., and Obsahuje bibliografické odkazy
The Rana Gruber iron oxide mining company in Norway has started to develop a new underground production level in order to continue operation in the Kvannevann mine. The planned change of mining system to sub-level caving (SLC) involves the removal of protective pillars below the former Kvannevann open-pit. Surface deformation on the hanging-wall and footwall sides of the deposit and caving of rock into the old pit is expected. When uncontrolled, this represents a threat to the underground mining operation below the open-pit. Trial removal of the protective pillar in the western part of the deposit has already caused fracturing of the rock mass on the hanging-wall side. Therefore, with the aim to monitor and control the rock mass deformation process in this area and ensure safe operation of the mine, a monitoring system based on periodic total station and GPS measurements in a three-tier control-measurement network has been developed and tested. In this paper the concept of this system, results of field work and recommendations for the system implementation is presented. The proposed concept has been used to implement a real system in the mine., Jan Blachowski, Steinar Ellefmo and Erik Ludvigsen., and Obsahuje bibliografii
In the paper, an attempt to interpret the PSInSAR data for the northern part of the Upper Silesian Coal Basin with the use o f kernel approximation is described. The PSI nSAR technique is characterised by the Permanent Scatterer points (so-called PS points, Permanent Scatterers), which usually correspond to the objects such as : buildings, industrial and transport infrastructure, and natural components of surface relief (Ferretti et. al., 2000, 2001). The PSInSAR technique allows to monitor ground movements. A non-uniform di stribution of the PS points makes the inte rpretation of PSInSAR data difficult, as well as the fact that one point can assume both positive an d negative values. The application of the kernel approximation for the interpretation of the PSInSAR data allowed of more unambiguous interpretation., Katarzyna Mirek and Janusz Mirek., and Obsahuje bibliografické odkazy
Determination of heights with help of GPS in local geodetic networks is still more actual respecting the fact that the GPS technology becames more and more effective with hardware progress, with improvements in measuring and evaluating procedures, and with better modelling of the disturbing influences. In comparison with GPS the employment of classical terrestrial measuring technologies is often more difficult namely in broken mountain environment. In period 1998-2005 authors carried out repeated measurements of GPS baselines of various length and various height differences in local geodynamical network Sněžník and in other experimental areas. On ground of analyses of large GPS data sets the modified procedure for GPS observation was designed. The procedure is based on repetition of shorter static sessions separated by time intervals of optimal length. This technology represents an alternative to the ususal long static sessions, and is offering better effectivity of vertical GPS measurements with minimal loss of accuracy. The paper presents detailed description of the modified procedure together with some statistical analyses of results. The possibilities of elimination or mitigation of some disturbing influences are discussed. Two testing vertical profiles were marked in Sněžník network- longitudinal profile in N-S direction, and transversal profile in E-W direction - which were measured in course of several years by classical method of very precise levelling, and also by modified GPS heighting procedure in repeated sessions. Results obtained contributed to the local quasigeoid model creation., Otakar Švábenský, Josef Weigel and Radovan Machotka., and Obsahuje bibliografii
At the end of 2010 seven TM 71 extensometers, installed at or near the active faults in Slovenia, were in operation. Three of them are on the surface and four inside karst caves. The highest rates with stable sense of movements were observed on the Idrija fault. Average horizontal displacement rate was 0.24 mm/year. Short term rates were even greater and reached 0.54 mm/year. The Raša fault first experienced an uplift of the SW block of 0.16 mm/year, which was followed by a short-term down-slip of the same block at the rate of 0.37 mm/year. Later the sense of movement returned to uplift with a rate of 0.05 mm/year. The average horizontal displacement was 0.07 mm/year. The Kneža fault experienced very small average displacements (y=0.035 mm/year, z=0.03 mm/year and x=0.02 mm/year). Similar rates were observed in nearby Polog cave (y=0.015 mm/year, z=0.027 mm/year and x=0.016 mm/year), which is located close to the seismically active Ravne fault. For Kostanjevica cave, located near the Brežice fault, small average rates are characteristic (y=0.006 mm/year, z=0.017 mm/year and x=0.012 mm/year). In Postojna cave, located close to the Predjama fault, two monitoring sites are very stable with small tectonic movements, including general dextral horizontal movement of 0.05 mm from 2004 to 2010 (Postojna 1) and two significant short-term peaks of 0.08 mm (Postojna 1-y and Postojna 2-z)., Andrej Gosar, Stanka Šebela, Blahoslav Košťák and Josef Stemberk., and Obsahuje bibliografii
Two geodynamic test transects across the Polish segment of the Western Carpathians, crossing the Orava Basin in the west (KO) and the Pieniny Klippen Belt and Magura Nappe along the Dunajec River valley in the east (DD), are presented. Multidisciplinary studies conducted along these transects incl uded gravimetric, geodetic, geologic and morphostructural investigations. Gravimetric and geodetic results appear to suggest recent subsidence of the Orava Basin, particularly intensive in the Wróblówka Graben, confirming conclusions derived from geomorphic analyses. Data ob tained for the Dunajec River transect do not show any particular differentiation among individual benchmarks, what can point to either minor uplift of the entire area (already suggested by the results of geomorphic and morphotectonic studies), minimal differences between successive slices of the Magura Nappe and the Pieniny Klippe n Belt, or both. Horizontal displacements of benchmarks, different for the KO and DD transects, towa rds the west and SW as well east and SE, respectively, can result from general uplift of the area comprised between these transects, i.e. the Gorce Mts., Monika Łój, Janusz Madej, Sławomir Porzucek and Witold Zuchiewicz., and Obsahuje bibliografické odkazy