NAMUR (BE)
Quarry blast13 April 2021
- Magnitude
- 1.2ML
- Depth
- –
- Belgian time
- 13:31:462021-04-13
- UTC
- 11:31:462021-04-13
Main parameters
| Date and time | 2021-04-13 11:31:46 UTC 2021-04-13 13:31:46 Belgian time |
|---|---|
| Magnitude | ML 1.2 |
| Epicentral coordinates | 50.485° N, 4.971° E Uncertainty ± 1.1 km |
| Event ID | ROB 13115 |
Data source : ROB (Royal Observatory of Belgium)
Last update : 2021-04-13 14:08:55 Belgian time
Location map
- Epicentre
- Station that recorded the event
Arrival times at the stations
Each station first records the P wave, the fastest, then the S wave. The farther a station is from the epicentre, the later the waves reach it and the wider the gap between the two.
- Stations
- 9
- Epicentral distance
- 13.9 – 91.8km
- Mean velocity, P wave
- 6.0km/s
- Mean velocity, S wave
- 3.4km/s
- P wave
- S wave
- Curve fitted to the measurements
Notes and method
Curves: travel time of a direct wave in a homogeneous medium. The velocity of each wave and an origin-time shift, common to both, are fitted to the measurements by least squares. Depth not determined: hypocenter placed at the surface for the calculation. P wave: 9 measurements, root-mean-square deviation 0.41 s. S wave: 9 measurements, root-mean-square deviation 0.71 s.
Station measurements
P- and S-wave arrivals and ground displacement measured at each station. Click a column heading to change the order.
| km | ° | UTC | UTC | s | |
|---|---|---|---|---|---|
| Belgian seismic network (Royal Observatory of Belgium)8 stations | |||||
| GESGesves | 13.9 | 143 | 11:31:48.76+2.19 s | 11:31:50.68+4.11 s | 1.92 |
| CLAClavier | 24.7 | 107 | 11:31:50.65+4.08 s | 11:31:54.32+7.75 s | 3.67 |
| MRDMaredsous | 25.0 | 215 | 11:31:51.05+4.48 s | 11:31:54.72+8.15 s | 3.67 |
| TGATangissart | 34.5 | 293 | 11:31:52.37+5.80 s | 11:31:57.27+10.70 s | 4.90 |
| RCHRochefort | 41.0 | 153 | 11:31:54.27+7.70 s | 11:31:59.94+13.37 s | 5.67 |
| DOUDourbes | 51.0 | 212 | 11:31:55.98+9.41 s | 11:32:02.14+15.57 s | 6.16 |
| MEMHMembach | 75.0 | 79 | 11:31:59.74+13.17 s | 11:32:10.46+23.89 s | 10.72 |
| KLBKalborn | 91.8 | 117 | 11:32:02.43+15.86 s | 11:32:12.77+26.20 s | 10.34 |
| Dutch seismic network (KNMI)1 station | |||||
| HGNHeimansgroeve | 74.7 | 65 | 11:31:58.83+12.26 s | 11:32:09.24+22.67 s | 10.41 |