TOURNAI (BE)
Quarry blast15 September 2020
- Magnitude
- 1.9ML
- Depth
- –
- Belgian time
- 13:00:222020-09-15
- UTC
- 11:00:222020-09-15
Main parameters
| Date and time | 2020-09-15 11:00:22 UTC 2020-09-15 13:00:22 Belgian time |
|---|---|
| Magnitude | ML 1.9 |
| Epicentral coordinates | 50.669° N, 3.398° E Uncertainty ± 22.1 km |
| Event ID | ROB 10885 |
Data source : ROB (Royal Observatory of Belgium)
Last update : 2020-09-17 10:16:53 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
- 7
- Epicentral distance
- 31.8 – 123.8km
- 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: 6 measurements, root-mean-square deviation 0.55 s. S wave: 5 measurements, root-mean-square deviation 0.50 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)7 stations | |||||
| LESLessines | 31.8 | 81 | 11:00:28.36+5.95 s | 11:00:32.19+9.78 s | 3.83 |
| SKQSteenkerque | 48.2 | 92 | 11:00:30.25+7.84 s | 11:00:36.22+13.81 s | 5.97 |
| BOUBougnies | 49.7 | 129 | 11:00:30.60+8.19 s | – | – |
| UCCBUccle | 69.4 | 78 | 11:00:33.87+11.46 s | 11:00:43.40+20.99 s | 9.53 |
| MRDMaredsous | 105.4 | 112 | 11:00:41.51+19.10 s | 11:00:54.02+31.61 s | 12.51 |
| DOUDourbes | 106.4 | 126 | 11:00:40.35+17.94 s | 11:00:53.19+30.78 s | 12.84 |
| GESGesves | 123.8 | 104 | 11:00:44.55+22.14 s | 11:00:59.53+37.12 s | 14.98 |