LESSINES (BE)
Quarry blast22 October 2021
- Magnitude
- 1.7ML
- Depth
- –
- Belgian time
- 13:44:422021-10-22
- UTC
- 11:44:422021-10-22
Main parameters
| Date and time | 2021-10-22 11:44:42 UTC 2021-10-22 13:44:42 Belgian time |
|---|---|
| Magnitude | ML 1.7 |
| Epicentral coordinates | 50.704° N, 3.841° E Uncertainty ± 11.0 km |
| Event ID | ROB 14640 |
Data source : ROB (Royal Observatory of Belgium)
Last update : 2021-10-22 16:24:47 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
- 10
- Epicentral distance
- 0.8 – 108.3km
- Mean velocity, P wave
- 5.4km/s
- Mean velocity, S wave
- 3.1km/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: 10 measurements, root-mean-square deviation 0.47 s. S wave: 4 measurements, root-mean-square deviation 0.49 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 | |||||
| LESLessines | 0.8 | 10 | 11:44:42.10+0.01 s | 11:44:42.28+0.19 s | 0.18 |
| SKQSteenkerque | 18.0 | 110 | 11:44:44.81+2.72 s | 11:44:46.62+4.53 s | 1.81 |
| RQRRonquières | 29.2 | 112 | 11:44:46.58+4.49 s | – | – |
| BRQBracquegnies | 32.4 | 140 | 11:44:47.82+5.73 s | – | – |
| SNFSeneffe | 38.0 | 124 | 11:44:48.32+6.23 s | 11:44:53.48+11.39 s | 5.16 |
| TGATangissart | 49.4 | 103 | 11:44:50.02+7.93 s | – | – |
| DOUDourbes | 86.4 | 141 | 11:44:57.67+15.58 s | – | – |
| GESGesves | 95.2 | 111 | 11:45:00.11+18.02 s | 11:45:12.72+30.63 s | 12.61 |
| DSLBDessel | 104.1 | 55 | 11:45:00.26+18.17 s | – | – |
| CLAClavier | 108.3 | 106 | 11:45:01.42+19.33 s | – | – |