This paper combines morphostructural analysis and geophysical methods in order to link the faults monitored inside Strašín Cave with faults and lineaments in the vicinity of the cave. The studied site is situated in SW Bohemia, at the foothills of the Bohemian Forest Mts. Main goal is to combine the morphostructural, morphometrical and geophysical methods in order to identify the fault system, monitored inside the cave. This will allow relevant interpretation of the observed movements in the frame of the local tectonic environment. The results show that the monitored faults are observable in the geophysical profiles and, using our knowledge of the structural setting, we have been able to link them with mapped tectonic structures in the vicinity of the cave. Thus, it has been demonstrated that even where outcrops are absent, the faults can be traced and that the monitored faults are significant enough to yield relevant data on tectonic movements. In addition, the combined resistivity and gravimetry profiles reveal a possible new, presently unknown, cave located 20 m below the surface about 200 m northnortheast of Strašín Cave., Filip Hartvich and Jan Valenta., and Obsahuje bibliografii
In order to utilize the absolute gravity ( AG) measurements in terms of tectonic study it is necessary to reduce all disturbing environmental and instrumental effects. Many of those can be easily modelled and this step is done routinely during measurements (i.e. tide, polar motion, ocean tidal loading). Other remains in data and there is a lack of conventional models for them. Significant gravity variation is associated with changes of soil water at global scale. We study this effect for the Lower Silesia (South-western Poland) territory. Computed gravity changes can reach up to 2 μgal peak-to-peak amplitude with seasonal time scale. This effect is beyond of accuracy of modern ballistic gravimeter. Using real data collected with FG5 gravimeter we show here that neglecting of this phenomenon can lead to serious misinterpretation in term of secular gravity changes. This is emphasized especially when only sparse data of a few year time span is at our disposal. No attempt of modelling of local hydrology impact on effect was made, while in this study we concentrate on large scale water storage influence on measured gravity., Marcin Rajner, Tomasz Olszak, Jerzy Rogowski and Janusz Walo., and Obsahuje bibliografické odkazy
The earthquakes of magnitudes ML=5.0 and 5.3 in the Kaliningrad enclave of Russia on September 21, 2004 were unexpected in a very low-seismicity area. The earthquakes caused minor damage in the Kaliningrad enclave, in northern Poland and in southwestern Lithuania, and macroseismic intensities of 6-7 (EMS) close to the epicenters. The earthquakes were felt up to 800 km distance. The events have been located under the central-northern part of the Sambia Penninsula at 16 and 20 km depth. Their source mechanism has been found to be a right lateral strike slip on a direction parallel to the edge of the Fennoscandian Shield and the East European Craton. The possible cause of the earthquakes is discussed. With the glaciotectonic cause unlikely, it seems the earthquakes evidence tectonic patterns, possibly resulting from stress propagating all across Europe from the Mediterranean region. Historical information seems to evidence past seismic activity in the region, which together with the 2004 earthquakes show the need to reassess seismic hazard in the area., Paweł Wiejacz., and Obsahuje bibliografii
This paper investigates the matrix porosity and related properties of a leucocratic granite from the Krudum Massif, West Bohemia. The required samples were obtained from the 30-year old core of borehole KZ-25 (Material Documentation Depositories). In total, nine sample sets were taken from different depth levels within the borehole ranging from 18 m to 108 m. The hydraulic conductivity of the granite matrix was measured using a pressure cell whilst standard methods were employed to determine the dry density, connected porosity and total porosity. The pore size distribution was analysed using mercury porosimetry. The ultrasonic velo cities were measured using a pulse source and oscilloscope. Dynamic Young’s modulus, dynamic shear modulus, Poisson’s ratio, static Young’ s modulus, uniaxial compressive strength and moisture were determined according to measurements of ultrasonic velocities and deformability in uniaxial compression. The morphology and structure of the pore network was studied using high reso lution scanning electron microscopy. The overall porosity values defined by the different porosimetry methods follow the same trends although the absolute values differ according to the specific method. A logarithmic relationship was found to exist between hydraulic conductivity and porosity within the granite matrix. In addition, a slight depth dependence was noted in the porosity, hydraulic conductivity, bulk density, and ultrasonic velocities of the granite matrix. The SEM images have allowed precise mapping and detailed de scription of the pore network., Lucie Nováková, Karel Sosna, Milan Brož, Jan Najser and Petr Novák., and Obsahuje bibliografické odkazy
A mineralogical study of the weathering crusts rich in P and Mn from the locality Hodušín - Božetice at Milevsko is presented. The locality belongs to the central part of the variegated group of Sušice and Votice in the Moldanubian Unit. From the analytical methods used, the IR-spectroscopy yielded satisfactory results. The main crust components subjected to weathering are apatite (of a CarHap B - dahllite type) and Mn-minerals (massive black psilomelane, the needle-aggregates probably comprise a poorly recrystallized psilomelane). Disintegrated rocks consist of a mixture of clay minerals, calcite and relicts of primary minerals (quartz, K-feldspars, albite, pyroxene and rutile). The origin and the source material of these crusts rich in P and Mn can not be unambiguously determined. Apatites without CL-effects indicate that the weathering crusts have originated in a strongly oxidative environment. Well documented neighbouring occurrences of phosphate minerals in the variegated group of Sušice and Votice are associated with graphitic rocks. Optical and quantitative chemical analyses of the rocks suggest that the source of apatite could possible be calc-silicate rocks (erlans) close to the graphitic rocks. Hypothetically, the metaphosphorite layers in the variegated Moldanubian Unit can also be considered a possible source of phosphorus., M. Brož, M. Kovářová, Z. Losos, M. Linhartová and V. Vávra., and Obsahuje bibliografii
The paper presents a method for measuring relative displacements of rock blocks on the basis of recorded images of prototype plate targets measurement. The developed measuring targets, after deposition on the surveyed object (for example rock blocks) act as control points, which represent the behavior of the object over time. Two types of targets ware constructed: passive (appropriately chosen figure) and active (respectively arranged fiber targets). The paper presents preliminary results of work in the laboratory using a calibrated semi-metric camera (Canon D5 Mark II - SLR camera with a CMOS 21 million pixels sensor), two passive targets, geodetic engineering tripod, micrometric simulator of shifts and Leica TC1800 total station. During the experimental work one of the targets was set on a tripod, and the other placed on the total station telescope set on the observation pillar. While taking a series of images the first target was fixed, while the other was moved and rotated. The displacements were made with a micrometric table in two mutually perpendicular directions XY in the horizontal plane, and by simulated rotation of the horizontal wheel and vertical wheel of the total station (rotation of the instrument by the adjusting screws). Using the principles of close-range mono-photogra mmetry from automatic measurement of the recorded images of both plate targets, the values of displacements and rotations were compared with the references., Piotr Gołuch, Kazimierz Ćmielewski, Janusz Kuchmistera and Krzysztof Kowalski., and Obsahuje bibliografické odkazy
The mountain type of climate, which is typical for the Sudety Mountains, is well known for its rapid and frequent changes in pressure, temperature and humidity. The fluctuations in meteorological parameters cause fast changes of the tropospheric delay, as a correlated value, and in consequence difficulties in GPS heights determination. The tropospheric delay is a function of the meteorological parameters obtained directly from synoptic stations and models. The paper presents the procedure of tropospheric delay estimation on the European Permanent Network and International GNSS Service (EPN/IGS) stations, using meteorological observations from synoptic stations (Wrocław Airport, Śnieżka) of the Polish Meteorology Service (IMGW), stations (Cervena, Praha-Kbely) of the Czech Hydrometeorological Institute (CHMU), and sensors mounted close to the antennas of the permanent GNSS stations (BISK, SNEC, WROC, GOPE). The values obtained from Global Pressure and Temperature (GPT) model were bases for the meteorological data calibration at EPN/IGS stations. The tropospheric delay (Zenith Total Delay - ZTD) on EPN/IGS stations was obtained from Saastamoinen formula and compared with ZTD from EPN solutions., Witold Rohm and Jarosław Bosy., and Obsahuje bibliografické odkazy
The article introduces the results achieved in the creation of feasible assemblies of NdFeB magnets assembled following an already published design of a practical arrangement of magnets derived from an ideal magnetization pattern, leading to the strongest possible stray field at a remote point. It presents a method of the implementation of these assembled sets and the relevant measured dependences of magnetic induction By = f(y) and By = f(x) including their comparison with already published dependences determined by a simulation. It further presents similar dependences of magnetic induction found in the case of a trial magnetic circuit with large blocks from NdFeB magnets, and these dependences are compared both with the mentioned computer-determined dependences and the dependences measured with the corresponding implemented assembly of magnets., Václav Žežulka and Pavel Straka., and Obsahuje bibliografii
Modal composition and grain-size characteri stics, physical and mechanical propertie s of three samples of Archean gneisses of the Kola series from the depths of 6.8 to 8.4 km of the Kola Superdeep Borehole (KSDB-3) and two collections of their surface analogues were analysed. On the basis of a comparison of the petrographic characteristics of the borehole samples and analogues, it was found that not all analogues are equivalents of corresponding core samples completely. Mechanical properties of core samples are affected by depth of the core sample position in the borehole. This work forms part of the research in the frame of the INTAS Project No.314 "Geodynamics in the cross-section of the Kola superdeep"., Jiřina Trčková, Vladimír Šrein, Martin Šťastný and Roman Živor., and Obsahuje bibliografické odkazy