## 2 Materials and Methods  
### Materials  
During the period from 1 January 2022 to 31 May 2023 [48], a total of 904 tremors related to underground coal mining were registered in the analyzed region of southern Poland, occurring in two mines (Figure 2). In both mines, extraction is carried out exclusively using the longwall system with caving. The seam is mined at heights ranging from 2.0 to 4.0 m. The longwalls are 200-300 m in length, and their main equipment includes mechanized shields, longwall shearers, and armored face conveyors. Coal extraction is conducted with roof caving, which affects the surface of the terrain, causing subsidence troughs and mining damage to both volumetric and linear structures. The geological profiles in the area of extraction are dominated by formations from the Quaternary and Carboniferous periods. Lithologically, the Quaternary formations consist mainly of sands and clays, while the Carboniferous formations comprise thick-bedded, variously grained sandstones interbedded with clay shales and coal seams. Figure 2: Localization of mining tremors in two underground mines, from January 2022 to May 2023 [49]. The numerical distribution of events in individual years and months of the study period is shown in Figures 3 and 4. As depicted in Figure 4, the highest number of tremors occurred during the spring and towards the end of 2022. In November and December, the number of events exceeded 100 per month. The events were characterized by the following energy values: 73.7% at \(<\)10\({}^{5}\) J, 24.0% at 10\({}^{6}\) J, 2.3% at 10\({}^{7}\) J, and one event at 10\({}^{8}\) J. The strongest tremor with an energy value of 10\({}^{8}\) J occurred on 24 December 2022, at 4:52 a.m. The percentage distribution of event energy is shown in Figure 5.  
Approximately 10 km from the underground mines, there is an open-pit mine extracting a dolomite deposit, where blasting operations are conducted using explosives. Two measurement stations of the MVMS system are installed in buildings surrounding this mine. The task of these stations is to monitor the impact of vibrations on buildings induced during blasting works. During the analyzed period, these stations recorded a  
Figure 4: Histogram of the number of mining tremors in individual months of the study period. Figure 3: Histogram of the number of events in underground mining facilities Mine I and Mine II, from January 2022 to May 2023.  
total of 318 vibrations related to mining tremors in the underground mines. Analyzing the number of events and their impact on the buildings where the MVMS stations were installed (Figure 6), it should be noted that since October 2022, the number of registrations has been steadily increasing, and in March 2023, it exceeded 40 registered events. This indicates an elevated level of event impact in the built-up area where the MVMS stations are installed. Figure 5: Energy of induced mining tremors in Mine I and Mine II—1 January 2022 to 31 May 2023. Figure 6: Histogram of the number of mining tremors and registrations of vibrations by MVMS stations from January 2022 to May 2023. As mentioned earlier, the task of MVMS stations is to document the impact of vibrations induced during blasting operations in the nearby open-pit mine on buildings. From January 2022 to May 2023, a total of 588 series of charges were detonated in the mine using long-hole blasting. The masses of the explosive charges are determined based on previously established constraints that consider the protection of buildings surrounding the mine. As a result, the blasting operations use the following parameters: total charge masses ranging from 135.0 kg to 1488.0 kg, and delay stage charge masses ranging from 7.4 kg to 80.0 kg (the mass of the explosive charge depends on the distance from the blasting site to the protected structures). Emulsion explosives or ANFO are used as the explosive materials, and the charges are initiated using a non-electric system. During this time, the MVMS system stations recorded 422 registrations (station No.