SOIGNIES (BE)
Quarry blast20 August 2021
- Magnitude
- 1.7ML
- Depth
- 10.0km
- Belgian time
- 13:00:392021-08-20
- UTC
- 11:00:392021-08-20
Main parameters
| Date and time | 2021-08-20 11:00:39 UTC 2021-08-20 13:00:39 Belgian time |
|---|---|
| Magnitude | ML 1.7 |
| Epicentral coordinates | 50.621° N, 4.023° E Uncertainty ± 7.0 km |
| Depth of hypocenter | 10.0 km |
| Event ID | ROB 14290 |
Data source : ROB (Royal Observatory of Belgium)
Last update : 2021-08-23 10:19:24 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
- 5.1 – 159.4km
- Mean velocity, P wave
- 5.6km/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. Hypocenter at a depth of 10.0 km. P wave: 6 measurements, root-mean-square deviation 0.47 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 | 5.1 | 53 | 11:00:41.17+1.40 s | – | – |
| LESLessines | 16.2 | 308 | 11:00:43.94+4.17 s | – | – |
| SNFSeneffe | 22.2 | 124 | 11:00:43.60+3.83 s | – | – |
| TGATangissart | 35.4 | 93 | 11:00:46.27+6.50 s | – | – |
| DOUDourbes | 71.3 | 145 | 11:00:52.89+13.12 s | – | – |
| GESGesves | 79.9 | 109 | 11:00:53.88+14.11 s | – | – |
| KLBKalborn | 159.4 | 111 | 11:01:06.08+26.31 s | – | – |
| Dutch seismic network (KNMI)1 station | |||||
| HGNHeimansgroeve | 135.8 | 83 | 11:01:04.69+24.92 s | – | – |