The oldest mine cavities of the Jeroným Mine were already mined out more than 400 years ago. That is why it is necessary to determine the stability of individual parts of underground spaces. The assessment of stability of mine cavities is based on the long-term monitoring of chosen parameters. A distributed measurement network has been operated here using several different types of sensors. A laser distance meter that is used for measuring the height of a large chamber is one of these sensors. The results obtained from this monitoring are presented. Even if no apparent correlation seems to be visible between Earth’s tides and LDM variations, some features of recorded data, like dynamical frequency crossover in the power spectrum, could be due to the tidal cycles of the Earth., Zdeněk Kaláb, Markéta Lednická, Jaromír Knejzlík and Luciano Telesca., and Obsahuje bibliografii
The past five centuries of the Idrija Mercury Mine’s operation have had consequences on the environment, which have directly influenced the deformations developing in the wider exploration area. During the many years of mercury ore exploitation, the cross-stope mining method with backfilling from bottom to top was used. This has strongly transformed the stress-strain field in the surrounding rocks and caused long-term deformation processes that are still in progress. This is because the deformations have a small time gradient and thus bigger breaks or faster sliding terrain above old mine workings are not expected. The surface movements are bigger in the area built of Permian-Carboniferous, low-bearing-capacity rocks, which in the past was destroyed by major tectonic movements in the rock structure. Mine closure works, which included grouting and hardening of destroyed underground areas, as well as filling parts of the mine and backfilling empty spaces (i.e., mine roadways, blind shafts), are finished. The efficiency of mine shutdown works is constantly being verified by means of geotechnical and other measurements and observations, and will continue in the future., Jakob Likar., and Obsahuje bibliografii