The present paper describes a method for identification of reflected waves on the seismogr ams from a cluster of quarry blasts. These reflections are used for determination of the Moho depth. Only one seismic station is sufficient, but a cluster of seismic sources is needed. To increase the signal-to-noise ratio of reflected waves, several techniques are applied, such as filtering, polarisation analysis and stacking of seismograms. Th e method was tested on seismic data from the central part of the Ore Mountains region, Czech Republic. Seismic waves were generated by strong quarry blasts at the Tušimice open-pit coal mine, and recorded at the Přísečnice (PRI) temporal seismic station at an epicentral distance of about 16 km. As the station was equipped with a three-component seismograph, also S-wave onsets could be determined. Although Pg, Sg and surface waves dominate the seismograms, weak Moho reflections of P and S waves could also be recognized at travel times of 9.7 s and 17.3 s, respectively. From these times we found the mean ratio of the P- to S-wave ve locities in the crust to be 1.78. Considering P-wave velocity model of Beránek (1971), the observed travel times of the reflections yield a crustal thickness of 29.5 -n31.5 km, which agrees with recent receiver function studies. These agreements indicate that the proposed method of reflected seismic waves, generated by quarry blasts, could represent a simple way for mapping the Moho discontinuity., Hana Kampfová, Jiří Málek and Oldřich Novotný., and Obsahuje bibliografické odkazy
A collaborative group between Greek, Polish, and Sl ovak colleagues installed a dense network of non-permanent GPS stations and extensometers to monitor active faults in the eastern part of the Gulf of Corinth, central Greece. The network includes eleven GPS stations across the Kaparelli fault and the Asopos rift valley to the east and two TM-71 extensometers that were installed on the Kaparelli fault plane. So far the G PS network has been measured in three campaigns within the last three years with very good accuracies (1-4 mm in the horizontal plane). Although it is early to draw conclusions on the velocity field and on strain patterns it can be noted that, the data from the extensometers demonstrate both fault-normal opening and shear motion. Given that the total offset on the Ka parelli fault is small, and the geological data suggesting a segmented character of this fault, we expect in the near fu ture to differentiate fault slip and strain accumulation among segments., Athanassios Ganas, Jaroslaw Bosy, Lubomir Petro, George Drakatos, Bernard Kontny, Marian Stercz, Nikolaos S. Melis, Stefan Cacon and Anastasia Kiratzi., and Obsahuje bibliografické odkazy
The medieval Jeroným Mine is a mine working in which places of various degrees of rock mass disintegration are there. Time-lapse recording, which has been performed in the Jeroným Mine since the year 2009, was induced by a necessity of documenting both areas of flaking-off and caved areas owing to an increased rate of occurrence of flaking-off phenomena in mine workings - rooms K3 and K4 of this mine. The methodology of recording, which uses as a basis repeated recording in time in the framework of geotechnical measurements carried out quarterly, is based on the principle of maintenance of not only parameters of images themselves, but also of location of a photo device used for documentation provision. This process is followed by the creation of information sheets of areas of flaking-off and caved areas and their classification. The method of recording was used owing to a high degree of disintegration of the rock mass in selected mine workings, a possibility of extension of caved areas and also the high rate of occurrence of subsidence phenomena occurring above those workings and even sporadically reaching the mine workings. Time-lapse recording is thus performed primarily in mine workings with reduced stability, situated very close to the surface. With regard to the principle of this method, results will be known only in further years., Radovan Kukutsch, Petr Žůrek and Martin Stolárik., and Obsahuje bibliografii
The Betic Cordillera, located at the westernmost end of the Mediterranean alpine belt, is deformed by overprinted folds and faults that produced the present-day relief since the Tortonian. In the frame of the COST 625 action, four sectors have been studied in the central part of the cordillera. In the Granad a Depression, the large NW-SE Padul normal fault deforms the SW periclinal end of the Sierra Nevada antiform. MT surveys in dicate the continuity in depth of high and low angle normal seismogenic faults and the presence of act ive detachment faults. In Tabernas regi on a good example of interaction between a N W-SE propagating normal fault, E-W strike-slip faults and the fold system is studied. In the Sierra Tejeda-Zafarraya and in the Balanegra-Sierra de Gádor areas, two new GPS networks ha ve been installed to determine the interaction and the development of large antiformal struct ures and normal faults with E-W and NW-SE orientations. However, taking into account the low tectonic activity of the studi ed region, a period of more than 5 year could be needed to determine with enough accuracy the development rate of the structures., Jesús Galindo-Zaldívar, Antonio Gil, Carlos Sanz de Galdeano, Stefan Shanov and Dumitru Stanica., and Obsahuje bibliografické odkazy
The paper presents the results of fieldwork and geodetic surveys carried out on a landslide in Wleń (Western Sudetes, Izerskie Foothills). This reactivated landslide occured firstly in 2011 and later on 16th July 2016, following heavy rainfall in the Lower Silesia region, and covered an area of ca. 1100 m2 above the renovated “Leśny Dwór” guesthouse in Wleń town. The main scarp of the landslide is built of strongly deformed Upper Permian (Zechstein) heterolithic deposits, composing the marginal part of the Wleń Graben - a NW-SE elongated, tectonic sub-unit within the North Sudetic Synclinorium. The landslide was a consequence of undercutting of steep slopes of the Bóbr River valley by anthropogenic activities and loading of the slope surface by blocks and pedestrian paths in the vicinity of the guesthouse. Monitoring of landslide activity was performed using the initial surface model of the slope subjected to mass movements, LiDAR elevation data, as well as 3D point cloud data from a non-metric camera on an Unmanned Aerial Vehicle (UAV). They were used to construct digital elevation models (DEMs) of the area covered by the landslide. The DEM from photogrammetric UAV data was processed using Structure from Motion (SfM) technology. The obtained dataset was verified by additional measurement series from terrestrial laser scanning (TLS). and Kowalski Aleksander, Wajs Jaroslaw, Kasza Damian.
The knowledge of the curing process of polysiloxane resin is an important factor for the optimal preparation of the precursor of ceramic materials/composites/. It was observed that different physical method explaining the cure process e.g. /IR, NMR/ and examined experimentally the method of dielectric analyses/DA/. It was found that the method DA with the addition of the dopant makes the monitored system to increase its conductivity for the certain type of polymer. This enables to influence the properties of the final composite during its curing with the help of the approprietly selected temperature and pressure depending on time., Petr Hron, Miloslav Burian, Šárka Hytychová, Adolf Inneman and Zbyněk Sucharda., 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
Assuring the stability of underground headings in order to fulfill their technical functions without any disturbance and provide a safe workplace for mining staff seems to be a fundamental issue in mining activity. In recent years, rockbolts: bar or cable have been most frequently applied as a means of reinforcement. Such a construction is often referred to as a stand-and-roofbolting support. The paper presents sample results of monitoring stand-and-roof-bolting support systems selected from numerous research projects carried out by the authors. The results discussed below are based on the measurements of the strength parameters of rocks in the laboratory and in-situ research, convergence of underground excavations, forces in rockbolts, separation of roof rock strata tested with extensometric probes, telltales and endoscopes, as well as steel yielding support frames load tested with dynamometers. The complex measurements of stand-and-roof-bolting supports along with specifications of geological, mining and geomechanical conditions allowed to formulate a proper evaluation of support behavior and its effectiveness for particular conditions., Zbigniew Niedbalski, Piotr Małkowski and Tadeusz Majcherczyk., and Obsahuje bibliografii
Ground deformations (e.g., landslide and subsidence) have substantially risen recently around Penang Island, Malaysia. The development of hillslopes for rapid urbanisation and heavy rainfall has detrimental impacts on Penang Island soil layers. Modelling, simulation, and the development of susceptibility maps were past methods used to predict potential ground deformations of Penang Island. There is no published work on the Interferometry Synthetic Aperture Radar (InSAR) technique, where ground deformation of the region has been holistically studied. This work integrates the Persistent Scatterer InSAR (PS-InSAR) technique with Ground Penetrating Radar (GPR) to monitor the deformation on the island and identify possible subsurface causes for the disturbance. Twenty-four descending Sentinel-1A datasets acquired between 14th July 2017 and 13th October 2018 were processed to monitor and map ground deformation areas with a focus on three selected regions- Batu Feringghi (BF), Paya Terubong (PT), and Tanjung Bungah (TB), where multiple landslides occurred between 2017 and 2018. InSAR results were later analysed using the Statistical Package for the Social Sciences (SPSS) tool and validated by the available Global Positioning System (GPS) analysis. InSAR analyses reveal the mean deformation values of -3.13 mm/yr, -2.76 mm/yr and -4.77 mm/yr for the BF, PT, and TB areas. GPR surveys were conducted with a 300/800 MHz dual-frequency antenna at the three selected study areas. Anomalies (wall cracks, road fissures, cavities, drains, and pipes) detected using GPR profiles correlated well with the permanent scatterer points calculated using the InSAR technique., Kazeem Olukunle Rauff and Ismail Ahmad Abir., and Obsahuje bibliografii
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