PECQ (BE)
Quarry blast17 September 2021
- Magnitude
- 1.9ML
- Depth
- –
- Belgian time
- 11:59:482021-09-17
- UTC
- 09:59:482021-09-17
Main parameters
| Date and time | 2021-09-17 09:59:48 UTC 2021-09-17 11:59:48 Belgian time |
|---|---|
| Magnitude | ML 1.9 |
| Epicentral coordinates | 50.717° N, 3.326° E Uncertainty ± 5.1 km |
| Event ID | ROB 14440 |
Data source : ROB (Royal Observatory of Belgium)
Last update : 2021-09-18 12:21:25 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
- 36.5 – 209.4km
- Mean velocity, P wave
- 5.9km/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: 7 measurements, root-mean-square deviation 0.31 s. S wave: 5 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)9 stations | |||||
| LESLessines | 36.5 | 91 | 09:59:54.42+6.31 s | 09:59:59.48+11.37 s | 5.06 |
| SKQSteenkerque | 53.8 | 98 | 09:59:57.77+9.66 s | 10:00:04.01+15.90 s | 6.24 |
| BOUBougnies | 57.0 | 129 | 09:59:58.17+10.06 s | – | – |
| BRQBracquegnies | 63.0 | 114 | 09:59:59.07+10.96 s | – | – |
| SNFSeneffe | 71.5 | 108 | 10:00:00.33+12.22 s | 10:00:09.15+21.04 s | 8.82 |
| MRDMaredsous | 112.2 | 114 | 10:00:06.97+18.86 s | 10:00:22.26+34.15 s | 15.29 |
| DOUDourbes | 113.7 | 127 | 10:00:08.23+20.12 s | 10:00:20.63+32.52 s | 12.40 |
| GESGesves | 130.1 | 106 | 10:00:10.02+21.91 s | 10:00:27.10+38.99 s | 17.08 |
| KLBKalborn | 209.4 | 108 | 10:00:21.19+33.08 s | 10:00:43.00+54.89 s | 21.81 |
| Dutch seismic network (KNMI)1 station | |||||
| HGNHeimansgroeve | 184.0 | 87 | 10:00:18.03+29.92 s | – | – |