PECQ (BE)
Quarry blast22 December 2020
- Magnitude
- 2.1ML
- Depth
- –
- Belgian time
- 13:00:022020-12-22
- UTC
- 12:00:022020-12-22
Main parameters
| Date and time | 2020-12-22 12:00:02 UTC 2020-12-22 13:00:02 Belgian time |
|---|---|
| Magnitude | ML 2.1 |
| Epicentral coordinates | 50.662° N, 3.364° E Uncertainty ± 24.4 km |
| Event ID | ROB 11605 |
Data source : ROB (Royal Observatory of Belgium)
Last update : 2020-12-22 14:57:03 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
- 34.3 – 144.0km
- Mean velocity, P wave
- 6.0km/s
- Mean velocity, S wave
- 3.5km/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 0.47 s. S wave: 5 measurements, root-mean-square deviation 0.66 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)10 stations | |||||
| LESLessines | 34.3 | 81 | 12:00:09.15+6.80 s | 12:00:12.84+10.49 s | 3.69 |
| SKQSteenkerque | 50.7 | 91 | 12:00:11.16+8.81 s | 12:00:17.20+14.85 s | 6.04 |
| BOUBougnies | 51.2 | 126 | 12:00:10.79+8.44 s | – | – |
| BRQBracquegnies | 58.3 | 110 | 12:00:11.46+9.11 s | – | – |
| TGATangissart | 82.2 | 94 | 12:00:16.26+13.91 s | 12:00:24.98+22.63 s | 8.72 |
| MRDMaredsous | 107.4 | 111 | 12:00:20.55+18.20 s | 12:00:34.04+31.69 s | 13.49 |
| DOUDourbes | 107.9 | 125 | 12:00:20.73+18.38 s | 12:00:34.06+31.71 s | 13.33 |
| GESGesves | 126.0 | 103 | 12:00:24.01+21.66 s | 12:00:40.78+38.43 s | 16.77 |
| CLAClavier | 140.0 | 100 | 12:00:26.31+23.96 s | 12:00:43.88+41.53 s | 17.57 |
| RCHRochefort | 144.0 | 112 | 12:00:27.58+25.23 s | 12:00:44.89+42.54 s | 17.31 |