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- Ma, Xu, et al.
(författare)
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Passive Seismic Imaging of Stress Evolution with Mining-Induced Seismicity at Hard-Rock Deep Mines
- 2020
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Ingår i: Rock Mechanics and Rock Engineering. - : Springer. - 0723-2632 .- 1434-453X. ; 53:6, s. 2789-2804
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Tidskriftsartikel (refereegranskat)abstract
- This work aims to examine the stress redistribution with evolving seismicity rates using a passive seismic tomographic tool. We compiled a total of 26,000 events from two underground mines and partitioned them into multiple clusters in a temporal sequence, each of which contains 1000 events. To image stress redistribution associated with seismicity rates, we then run the tomographic studies using each cluster to yield seismic tomograms and computed the corresponding seismicity rate. We found that high velocity anomalies grew with the increase of seismicity rates, and they switched to a shrinking tendency under low seismicity rates. Results of this study imply that seismicity rates increase with increasing stress concentration and decrease with decreasing stress concentration. This study highlights the value of utilizing passive seismic tomography for estimating stress evolution associated with the change of seismicity rates at underground mines. Our findings illuminate the applications of using mining-induced seismicity to assess stress redistribution associated with seismicity rates at hard-rock mines, providing insights into seismic hazards for deep mining.
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2. |
- Ma, Xu, et al.
(författare)
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Stress Redistribution Monitoring Using Passive Seismic Tomography at a Deep Nickel Mine
- 2019
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Ingår i: Rock Mechanics and Rock Engineering. - : Springer. - 0723-2632 .- 1434-453X. ; 52:10, s. 3909-3919
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Tidskriftsartikel (refereegranskat)abstract
- High magnitude seismic events (HMSE), also called major events, triggered at underground mines can severely threaten safety and structures in mines. The aims of this work are to assess stress evolution with the occurrence of them and identify patterns in stress change. Several methods were used to help understand the stress redistribution and rock mass behavior related to two HMSE with moment magnitude greater than 1.0 in a deep nickel mine. Approximately 46,500 seismic events were compiled with 2 HMSE at this mine and used seismic tomography to obtain high-resolution images and temporal-spatial velocity changes before and after these events. This work exhibited surrounding stress evolution and geological structures. Seismic imaging results show that velocity increased in the nearby regions of HMSE before they were triggered. Stress subsequently reduced in the relaxation process after the occurrence of HMSE. Conversely, regions predominantly occupied by low-velocity anomalies increased to higher stress levels after HMSE. Overall, the stress redistributed toward an equilibrium state following HMSE. This study highlights the value of utilizing seismic tomography for estimating stress evolution associated with HMSE. The findings illuminate the applications of seismic imaging around HMSE of hard-rock mines, providing insights into seismic hazard mitigation for deep mining.
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