TOURNAI (BE)
Quarry blast7 May 2021
- Magnitude
- 2.1ML
- Depth
- –
- Belgian time
- 13:53:332021-05-07
- UTC
- 11:53:332021-05-07
Main parameters
| Date and time | 2021-05-07 11:53:33 UTC 2021-05-07 13:53:33 Belgian time |
|---|---|
| Magnitude | ML 2.1 |
| Epicentral coordinates | 50.643° N, 3.524° E Uncertainty ± 2.5 km |
| Event ID | ROB 13345 |
Data source : ROB (Royal Observatory of Belgium)
Last update : 2021-05-07 16:35:50 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
- 23.8 – 193.6km
- Mean velocity, P wave
- 5.8km/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: 10 measurements, root-mean-square deviation 0.86 s. S wave: 7 measurements, root-mean-square deviation 0.68 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)14 stations | |||||
| LESLessines | 23.8 | 71 | 11:53:36.51+3.34 s | 11:53:41.54+8.37 s | 5.03 |
| SKQSteenkerque | 39.3 | 89 | 11:53:39.83+6.66 s | 11:53:45.74+12.57 s | 5.91 |
| RQRRonquières | 49.8 | 94 | 11:53:41.50+8.33 s | 11:53:49.06+15.89 s | 7.56 |
| SNFSeneffe | 55.8 | 105 | 11:53:42.30+9.13 s | – | – |
| UCCBUccle | 61.5 | 73 | 11:53:43.84+10.67 s | 11:53:51.09+17.92 s | 7.25 |
| TGATangissart | 70.7 | 93 | 11:53:44.98+11.81 s | – | – |
| OSTBOostende | 77.9 | 328 | 11:53:46.56+13.39 s | – | – |
| MRDMaredsous | 96.1 | 113 | 11:53:51.52+18.35 s | 11:54:01.66+28.49 s | 10.14 |
| DOUDourbes | 97.6 | 128 | 11:53:51.58+18.41 s | 11:54:01.67+28.50 s | 10.09 |
| GESGesves | 114.5 | 104 | 11:53:52.21+19.04 s | 11:54:07.05+33.88 s | 14.84 |
| MOL1Mol | 126.8 | 59 | 11:53:54.07+20.90 s | – | – |
| CLAClavier | 128.5 | 100 | 11:53:55.91+22.74 s | 11:54:12.23+39.06 s | 16.32 |
| RCHRochefort | 132.7 | 113 | 11:53:55.95+22.78 s | 11:54:11.10+37.93 s | 15.15 |
| KLBKalborn | 193.6 | 107 | 11:54:04.10+30.93 s | – | – |