TOURNAI (BE)
Quarry blast17 November 2020
- Magnitude
- 1.8ML
- Depth
- –
- Belgian time
- 13:05:082020-11-17
- UTC
- 12:05:082020-11-17
Main parameters
| Date and time | 2020-11-17 12:05:08 UTC 2020-11-17 13:05:08 Belgian time |
|---|---|
| Magnitude | ML 1.8 |
| Epicentral coordinates | 50.643° N, 3.521° E Uncertainty ± 3.8 km |
| Event ID | ROB 11355 |
Data source : ROB (Royal Observatory of Belgium)
Last update : 2020-11-20 12:07:29 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
- 13
- Epicentral distance
- 39.5 – 170.8km
- Mean velocity, P wave
- 6.2km/s
- Mean velocity, S wave
- 3.3km/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 0.31 s. S wave: 7 measurements, root-mean-square deviation 1.13 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)12 stations | |||||
| SKQSteenkerque | 39.5 | 89 | 12:05:15.24+7.10 s | 12:05:21.18+13.04 s | 5.94 |
| BRQBracquegnies | 47.1 | 112 | 12:05:17.03+8.89 s | – | – |
| RQRRonquières | 50.0 | 94 | 12:05:16.75+8.61 s | 12:05:24.54+16.40 s | 7.79 |
| SNFSeneffe | 56.0 | 105 | 12:05:17.57+9.43 s | 12:05:26.68+18.54 s | 9.11 |
| UCCBUccle | 61.7 | 74 | 12:05:19.24+11.10 s | 12:05:26.30+18.16 s | 7.06 |
| TGATangissart | 71.0 | 93 | 12:05:19.87+11.73 s | – | – |
| OSTBOostende | 77.8 | 329 | 12:05:21.47+13.33 s | 12:05:30.28+22.14 s | 8.81 |
| MRDMaredsous | 96.3 | 113 | 12:05:24.10+15.96 s | – | – |
| DOUDourbes | 97.7 | 128 | 12:05:24.78+16.64 s | 12:05:37.88+29.74 s | 13.10 |
| GESGesves | 114.7 | 104 | 12:05:27.56+19.42 s | 12:05:44.78+36.64 s | 17.22 |
| CLAClavier | 128.7 | 100 | 12:05:30.79+22.65 s | 12:05:49.58+41.44 s | 18.79 |
| RCHRochefort | 132.9 | 113 | 12:05:31.79+23.65 s | 12:05:48.33+40.19 s | 16.54 |
| Dutch seismic network (KNMI)1 station | |||||
| HGNHeimansgroeve | 170.8 | 85 | 12:05:36.34+28.20 s | – | – |