Special regulations have been laid down to establish the principles and requirements for the safety and serviceability of old mining workings which are adapted for tourism. To comply with these regulations the measurements were taken in the Bochnia Salt Mine, which has been in use for 800 years. The presented work demonstrates the use of a sonic probe extensometer in connection with the obtained results of displacement measurements in intact rocks surrounding the gallery. There were also test measurements carried out for determination of the real accuracy of the instrument. The presented study of deformations detected by electromagnetic extensometer measurements is presumed to be the first time that research has been made in salt mines operating in rock mass affected by tectonic stress. The paper presents the process of rock salt flow into the gallery observed over a period of 3 years. It is an unprecedented depiction of salt deformation subjected to natural stresses. One of the more surprising results presented here is the discovery of the occurrence of a specific distribution of strain around the measured gallery. The results of measurements showed that the southern part of the intact rock mass surrounding the passage is more compressed (strain rate 3.6 mm/m/year) than the northern one (strain rate 1.6 mm/m/year). This illustrates the presence and influence of additional tectonic effects resulting from the Carpathian push. These observations represent a new kind of research into tectonic stress and tectonic activity in underground measurements.

The presented work deals with the problem of terrain surface and rock mass deformation in the area of the Bochnia Salt Mine. The deformations are related to natural causes (mainly the tectonic stress of the Carpathian orogen) as well as anthropogenic ones related to the past mining activity conducted directly under the buildings of the town of Bochnia. The discussed characteristics of land surface deformation are important from the point of view of threats to surface features and contribute to spatial development. Particularly anomalous zones of observed subsidence basins are examined as places of second order deformation effects. The author presents a method of determinations of these anomalous areas and he discusses their origins.

Seismic events in the area of Poland are related mostly to copper and coal mining, and they are regarded as the most dangerous natural hazard. Although development of geomechanical modelling as the development of geophysical methods determining seismic hazard are evident, low predictability of the time-effect relationship still remains. Geomechanical models as geophysical data analysis highlight the interaction between parts of rock mass or allow to reconstruct the way of rock mass destruction and to understand the processes that take place in the high-energy tremors. However, the association of larger mining tremors with pre-existing geological features has been reported by many investigators; in geomechanical practice, investigations of rock mass condition concentrate on this problem in the local scale. Therefore, the problem of relations between high-energy seismic events in Legnica–Głogów Copper District (LGCD) and regional scale deformations of terrain surface resulting from possible tectonic activity is discussed in this paper. The GNSS data evaluated from the observations of ASG-EUPOS (Active Geodetic Network – EUPOS) stations in the area of LGCD and in the adjacent areas is analysed in this study. Temporal variation of distances between the stations and evaluated on that base so called apparent strain was combined with the occurrence of high-energy tremors. Consequently, after the examination and analysis of occurrences of mining tremors, it is found that high-energy seismic events and periods of strain accumulation evaluated from GPS/GNSS data have temporal relations. Although the seismic events were triggered by mining, nearly all the events with energy E > 10 ⁸ J occurred in the periods when the analysed stations’ positions demonstrated a decrease in the baseline length.

The GNSS data evaluated from on observation of ASG EUPOS stations in the Sudety Mts. and in adjacent areas is analyzed by the author in the scope of disturbances in daily solutions that can be induced by tectonics stress. The daily position changes derived from GNSS data demonstrate the long or short term trends, which are affected by offsets of different nature. Author presents an analysis based on frequency of parameter – displacement vector azimuth. The aim of the analysis is to show statistical significance of observed small values of temporal displacements, which values are not normally distributed. There are “outliers” of the normal distribution of displacement azimuths, which values show a certain reproducibility, which corresponds to orientations of tectonic lines. That suggests small, short time movements along boundaries of horsts and grabens – a crustal-extension structure of the area. However derived results (values of displacements) are less than a limitation error, temporal distributions of coordinates are not random as usually data errors. So in author’s opinion the spatial-temporal evolution of horizontal displacements of ASG EUPOS stations in the Sudety Mts. and in adjacent areas are determined by expressions of underlying geological structures

The authors discuss a case that is full of examples of the problems faced by civil engineers whose task is to develop areas in the face of natural, technological, or post-mining hazards. The study area is in the central part of Inowrocław, a town located on a massive salt dome of Zechstein salts. A strong deformation zone expanded in its upper part; this was caused by a natural process (related to so-called salt karst) and by mining activities that occurred in the past, creating a problem with regard to any potential spatial development in the town. The authors show a combination of data obtained using gravimetric and geodetic methods, which helps us to assess the geohazard risk. These include remote sensing data, which can be used to evaluate displacements of the ground surface. The authors used an approach that they term the Elevation Difference Method. This consists of determining displacements between ground surfaces: estimated on the basis of remote sensing data and on the basis of the historical data, when mounted measurement points (and remote sensing data) did not exist. The authors discuss the results in the light of the geological background. Within the area of the study, the displacements of the positive values dominate. The displacement occurs at 6 mm/yr on average and indicates diapiric uplift movement. The results are important for the town authorities for planning and development and for infrastructure management.