Seismicity induced by hard coal mining in the vicinity of faults

Abstract

An inherent feature of Polish collieries within the Upper Silesia Coal Basin is the high level of mining induced seismicity, resulting in elevated rockburst hazard levels. One of the major causes of high-energy seismic events is that mining operations are continued in the vicinity of major faulting zones. The study summarises the results of geo-mechanical and statistical analysis of mining-induced seismic activity in the region of major faults, in a selected section within a colliery. Seismic activity assessment involves the categorisation of seismic events due to tectonic movements in the context of various face development systems with respect to the faulting zone: perpendicular (advancing towards the faulting zone or retreating) or parallel (along the faulting zone). Registered seismic activity was analysed in the context of epicenter locations and variations of seismic activity in relation to the developing face operations in the function of time and energy ratings (Gutenberg-Richter formulas). Results have demonstrated that increased levels of seismic activity in the strata can be attributable to mining operations in the vicinity of major faulting zones.

Regional seismic activity in relation to tectonic structure in the PGG S.A. coal mines

“…Exploitation of coal deposits in the Upper Silesian Coal Basin (USCB) causes a disturbance of the balance of stress in the rock mass, both in the immediate and further vicinity of excavations [1,2]. The consequence of this process is, among others, the occurrence of rock mass tremors [3,4,5]. These phenomena in USCB are monitored by two independent registration systems: mine seismological networks and the regional system -the Upper Silesian Regional Seismological Network (GRSS) of the Central Mining Institute and local network in coal mines.…”