Sen, Ali Tolga and Cesca, Simone and Bischoff, M. and Meier, Th. and Dahm, Torsten (2013) Automated full moment tensor inversion of coal mining-induced seismicity. Geophysical Journal International, 195 (2). pp. 1267-1281. DOI: https://doi.org/10.1093/gji/ggt300
Full text not available from this repository.Abstract
Seismicity induced by coal mining in the Ruhr region, Germany, has been monitored continuously over the last 25 yr. In 2006, a dense temporary network (HAMNET) was deployed to locally monitor seismicity induced by longwall mining close to the town of Hamm. Between 2006 July and 2007 July, more than 7000 events with magnitudes ML from −1.7 to 2.0 were detected. The spatiotemporal distribution of seismicity shows high correlation with the mining activity. In order to monitor rupture processes, we set up an automated source inversion routine and successfully perform double couple and full moment tensor (MT) inversions for more than 1000 events with magnitudes above ML −0.5. The source inversion is based on a full waveform approach, both in the frequency and in the time domain, providing information about the centroid location, focal mechanism, scalar moment and full MT. Inversion results indicate a strong dominance of normal faulting focal mechanisms, with a steeper plane and a subhorizontal one. Fault planes are oriented parallel to the mining stopes. We classify the focal mechanisms based on their orientation and observe different frequency-magnitude distributions for families of events with different focal mechanisms; the overall frequency-magnitude distribution is not fitting the Gutenberg–Richter relation. Full MTs indicate that non-negligible opening tensile components accompanied normal faulting source mechanisms. Finally, extended source models are investigated for largest events. Results suggest that the rupture processes mostly occurred along the subvertical planes.
| Item Type: | Article |
|---|---|
| Uncontrolled Keywords: | Geomechanics Fracture and flow Earthquake source observations Seismicity and tectonics |
| Subjects: | Methodology > Method and procesing > Source parameter estimation Region > Germany > Ruhr area Inducing technology > Underground mining |