NAMUR (BE)
Quarry blast25 May 2021
- Magnitude
- 1.4ML
- Depth
- –
- Belgian time
- 14:36:302021-05-25
- UTC
- 12:36:302021-05-25
Main parameters
| Date and time | 2021-05-25 12:36:30 UTC 2021-05-25 14:36:30 Belgian time |
|---|---|
| Magnitude | ML 1.4 |
| Epicentral coordinates | 50.494° N, 4.966° E Uncertainty ± 1.1 km |
| Event ID | ROB 13520 |
Data source : ROB (Royal Observatory of Belgium)
Last update : 2021-05-25 16:28:36 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
- 11
- Epicentral distance
- 14.8 – 75.1km
- Mean velocity, P wave
- 5.9km/s
- Mean velocity, S wave
- 3.3km/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: 11 measurements, root-mean-square deviation 0.37 s. S wave: 7 measurements, root-mean-square deviation 0.43 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)10 stations | |||||
| GESGesves | 14.8 | 145 | 12:36:33.12+2.36 s | 12:36:35.42+4.66 s | 2.30 |
| CLAClavier | 25.2 | 109 | 12:36:35.24+4.48 s | 12:36:38.56+7.80 s | 3.32 |
| MRDMaredsous | 25.6 | 214 | 12:36:35.65+4.89 s | 12:36:39.63+8.87 s | 3.98 |
| TGATangissart | 33.8 | 292 | 12:36:36.81+6.05 s | 12:36:40.98+10.22 s | 4.17 |
| RCHRochefort | 42.0 | 154 | 12:36:37.88+7.12 s | 12:36:43.09+12.33 s | 5.21 |
| LCHLa Chartreuse | 47.7 | 70 | 12:36:39.31+8.55 s | – | – |
| DOUDourbes | 51.6 | 211 | 12:36:40.47+9.71 s | 12:36:46.38+15.62 s | 5.91 |
| RQRRonquières | 54.0 | 284 | 12:36:39.91+9.15 s | – | – |
| SKQSteenkerque | 65.1 | 286 | 12:36:41.74+10.98 s | – | – |
| MEMHMembach | 75.1 | 80 | 12:36:44.28+13.52 s | – | – |
| Dutch seismic network (KNMI)1 station | |||||
| HGNHeimansgroeve | 74.6 | 66 | 12:36:43.21+12.45 s | 12:36:53.63+22.87 s | 10.42 |