TOURNAI (BE)
Quarry blast20 May 2021
- Magnitude
- 2.2ML
- Depth
- –
- Belgian time
- 13:01:062021-05-20
- UTC
- 11:01:062021-05-20
Main parameters
| Date and time | 2021-05-20 11:01:06 UTC 2021-05-20 13:01:06 Belgian time |
|---|---|
| Magnitude | ML 2.2 |
| Epicentral coordinates | 50.638° N, 3.530° E Uncertainty ± 1.5 km |
| Event ID | ROB 13490 |
Data source : ROB (Royal Observatory of Belgium)
Last update : 2021-05-21 16:51:02 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
- 14
- Epicentral distance
- 38.9 – 193.0km
- Mean velocity, P wave
- 6.1km/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: 11 measurements, root-mean-square deviation 0.19 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)13 stations | |||||
| SKQSteenkerque | 38.9 | 88 | 11:01:13.54+6.96 s | 11:01:18.58+12.00 s | 5.04 |
| BOUBougnies | 40.4 | 133 | 11:01:13.76+7.18 s | – | – |
| BRQBracquegnies | 46.3 | 112 | 11:01:14.72+8.14 s | – | – |
| RQRRonquières | 49.3 | 94 | 11:01:15.00+8.42 s | – | – |
| SNFSeneffe | 55.2 | 104 | 11:01:15.94+9.36 s | – | – |
| UCCBUccle | 61.2 | 73 | 11:01:17.63+11.05 s | 11:01:25.80+19.22 s | 8.17 |
| TGATangissart | 70.3 | 93 | 11:01:18.37+11.79 s | – | – |
| OSTBOostende | 78.6 | 328 | 11:01:20.07+13.49 s | – | – |
| MRDMaredsous | 95.5 | 113 | 11:01:22.80+16.22 s | – | – |
| DOUDourbes | 96.9 | 128 | 11:01:23.07+16.49 s | 11:01:36.09+29.51 s | 13.02 |
| GESGesves | 114.0 | 104 | 11:01:25.85+19.27 s | – | – |
| RCHRochefort | 132.1 | 113 | 11:01:29.01+22.43 s | – | – |
| KLBKalborn | 193.0 | 107 | 11:01:37.92+31.34 s | 11:01:59.68+53.10 s | 21.76 |
| Dutch seismic network (KNMI)1 station | |||||
| HGNHeimansgroeve | 170.2 | 84 | 11:01:34.77+28.19 s | 11:01:56.30+49.72 s | 21.53 |