TOURNAI (BE)
Quarry blast15 June 2021
- Magnitude
- 1.9ML
- Depth
- –
- Belgian time
- 13:00:322021-06-15
- UTC
- 11:00:322021-06-15
Main parameters
| Date and time | 2021-06-15 11:00:32 UTC 2021-06-15 13:00:32 Belgian time |
|---|---|
| Magnitude | ML 1.9 |
| Epicentral coordinates | 50.643° N, 3.373° E Uncertainty ± 6.6 km |
| Event ID | ROB 13695 |
Data source : ROB (Royal Observatory of Belgium)
Last update : 2021-06-18 11:16:06 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
- 8
- Epicentral distance
- 49.4 – 203.8km
- Mean velocity, P wave
- 5.1km/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 0.23 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)8 stations | |||||
| BOUBougnies | 49.4 | 125 | 11:00:40.23+8.12 s | – | – |
| SKQSteenkerque | 50.0 | 89 | 11:00:40.72+8.61 s | 11:00:46.48+14.37 s | 5.76 |
| BRQBracquegnies | 57.0 | 108 | 11:00:41.83+9.72 s | – | – |
| RQRRonquières | 60.4 | 94 | 11:00:42.43+10.32 s | – | – |
| SNFSeneffe | 66.2 | 102 | 11:00:43.12+11.01 s | – | – |
| DOUDourbes | 106.2 | 125 | 11:00:51.49+19.38 s | 11:01:04.62+32.51 s | 13.13 |
| GESGesves | 124.9 | 103 | 11:00:52.87+20.76 s | 11:01:09.70+37.59 s | 16.83 |
| KLBKalborn | 203.8 | 106 | 11:01:05.11+33.00 s | 11:01:27.68+55.57 s | 22.57 |