REBECQ (BE)
Quarry blast22 February 2021
- Magnitude
- 1.4ML
- Depth
- –
- Belgian time
- 14:16:452021-02-22
- UTC
- 13:16:452021-02-22
Main parameters
| Date and time | 2021-02-22 13:16:45 UTC 2021-02-22 14:16:45 Belgian time |
|---|---|
| Magnitude | ML 1.4 |
| Epicentral coordinates | 50.655° N, 4.136° E Uncertainty ± 2.1 km |
| Event ID | ROB 12420 |
Data source : ROB (Royal Observatory of Belgium)
Last update : 2021-02-23 11:15:20 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
- 8
- Epicentral distance
- 4.0 – 127.4km
- Mean velocity, P wave
- 6.1km/s
- Mean velocity, S wave
- 3.6km/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: 7 measurements, root-mean-square deviation 0.46 s. S wave: 5 measurements, root-mean-square deviation 1.07 s.
Stations farther than 120 km are left out of the fit: the first waves to reach them have travelled beneath the crust, through the mantle, where they propagate faster.
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)7 stations | |||||
| SKQSteenkerque | 4.0 | 261 | 13:16:46.43+1.28 s | 13:16:47.04+1.89 s | 0.61 |
| RQRRonquières | 8.3 | 131 | 13:16:46.81+1.66 s | – | – |
| UCCBUccle | 22.4 | 45 | 13:16:49.10+3.95 s | – | – |
| TGATangissart | 27.9 | 101 | 13:16:49.88+4.73 s | 13:16:53.24+8.09 s | 3.36 |
| MRDMaredsous | 59.6 | 131 | 13:16:55.49+10.34 s | 13:17:01.93+16.78 s | 6.44 |
| DOUDourbes | 70.3 | 152 | 13:16:56.26+11.11 s | 13:17:07.07+21.92 s | 10.81 |
| GESGesves | 73.8 | 114 | 13:16:58.44+13.29 s | 13:17:04.75+19.60 s | 6.31 |
| Dutch seismic network (KNMI)1 station | |||||
| HGNHeimansgroeve | 127.4 | 84 | 13:17:03.35+18.20 s | – | – |