ANDENNE (BE)
Quarry blast6 July 2021
- Magnitude
- 1.8ML
- Depth
- –
- Belgian time
- 13:50:082021-07-06
- UTC
- 11:50:082021-07-06
Main parameters
| Date and time | 2021-07-06 11:50:08 UTC 2021-07-06 13:50:08 Belgian time |
|---|---|
| Magnitude | ML 1.8 |
| Epicentral coordinates | 50.488° N, 4.984° E Uncertainty ± 1.4 km |
| Event ID | ROB 13890 |
Data source : ROB (Royal Observatory of Belgium)
Last update : 2021-07-06 17:07:22 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
- 23.8 – 74.0km
- Mean velocity, P wave
- 6.2km/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 0.47 s. S wave: 7 measurements, root-mean-square deviation 0.52 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 | |||||
| CLAClavier | 23.8 | 109 | 11:50:13.06+4.22 s | 11:50:16.37+7.53 s | 3.31 |
| MRDMaredsous | 25.8 | 217 | 11:50:13.31+4.47 s | 11:50:17.82+8.98 s | 4.51 |
| RCHRochefort | 40.9 | 155 | 11:50:15.99+7.15 s | 11:50:21.68+12.84 s | 5.69 |
| DOUDourbes | 51.8 | 213 | 11:50:18.05+9.21 s | 11:50:24.11+15.27 s | 6.06 |
| RQRRonquières | 55.4 | 284 | 11:50:17.76+8.92 s | – | – |
| SKQSteenkerque | 66.5 | 286 | 11:50:19.54+10.70 s | 11:50:29.54+20.70 s | 10.00 |
| MEMHMembach | 73.9 | 79 | 11:50:22.30+13.46 s | – | – |
| HOUHouvegnez | 74.0 | 101 | 11:50:21.72+12.88 s | 11:50:30.50+21.66 s | 8.78 |
| Dutch seismic network (KNMI)1 station | |||||
| HGNHeimansgroeve | 73.7 | 65 | 11:50:21.15+12.31 s | 11:50:31.36+22.52 s | 10.21 |