Passive Seismic Velocity Tomography and Geostatistical Simulation on Longwall Mining Panel

Abstract

Generally, the accurate determination of the stress in surrounding rock mass of underground miningarea has an important role in stability and ground control. In this paper stress redistribution around thelongwall face has been studied using passive seismic velocity tomography based on Simultaneous IterativeReconstructive Technique (SIRT) and Sequential Gaussian Simulation (SGS). The mining-induced microseismicevents are used as a passive source. Since such sources are used, the ray coverage is insufficientand in order to resolve this deficiency, the wave velocity is estimated in a denser network and by the SGSmethod. Consequently the three-dimensional images of wave velocity are created and sliced into the coalseam. To analyze the variations of stress around the panel during the study period, these images are interpreted.Results show that the state of stress redistribution around the longwall panel can be deduced fromthese velocity images. In addition, movements of the stressed zones, including front and side abutmentsand the goaf area, along the longwall face are evident. The applied approach illustrated in this paper canbe used as a useful method to monitoring the stress changes around the longwall face continuously. Thiscan have significant safety implications and contribute to improvements in operational productivity.