TOURNAI (BE)
Quarry blast16 April 2021
- Magnitude
- 1.2ML
- Depth
- –
- Belgian time
- 11:00:172021-04-16
- UTC
- 09:00:172021-04-16
Main parameters
| Date and time | 2021-04-16 09:00:17 UTC 2021-04-16 11:00:17 Belgian time |
|---|---|
| Magnitude | ML 1.2 |
| Epicentral coordinates | 50.652° N, 3.575° E Uncertainty ± 1.9 km |
| Event ID | ROB 13160 |
Data source : ROB (Royal Observatory of Belgium)
Last update : 2021-04-16 13:28:22 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
- 35.7 – 129.8km
- Mean velocity, P wave
- 5.5km/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: 9 measurements, root-mean-square deviation 0.49 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 | |||||
| SKQSteenkerque | 35.7 | 90 | 09:00:23.96+6.82 s | – | – |
| BOUBougnies | 39.3 | 138 | 09:00:24.25+7.11 s | – | – |
| BRQBracquegnies | 44.1 | 115 | 09:00:25.06+7.92 s | – | – |
| RQRRonquières | 46.3 | 96 | 09:00:25.45+8.31 s | – | – |
| SNFSeneffe | 52.6 | 107 | 09:00:26.41+9.27 s | – | – |
| UCCBUccle | 57.7 | 73 | 09:00:27.41+10.27 s | 09:00:34.83+17.69 s | 7.42 |
| OSTBOostende | 79.0 | 326 | 09:00:30.64+13.50 s | – | – |
| DOUDourbes | 95.4 | 130 | 09:00:33.62+16.48 s | 09:00:44.33+27.19 s | 10.71 |
| GESGesves | 111.3 | 105 | 09:00:38.15+21.01 s | 09:00:48.73+31.59 s | 10.58 |
| RCHRochefort | 129.8 | 115 | 09:00:40.06+22.92 s | – | – |