LESSINES (BE)
Quarry blast10 September 2021
- Magnitude
- 1.3ML
- Depth
- –
- Belgian time
- 13:43:462021-09-10
- UTC
- 11:43:462021-09-10
Main parameters
| Date and time | 2021-09-10 11:43:46 UTC 2021-09-10 13:43:46 Belgian time |
|---|---|
| Magnitude | ML 1.3 |
| Epicentral coordinates | 50.694° N, 3.843° E Uncertainty ± 7.4 km |
| Event ID | ROB 14405 |
Data source : ROB (Royal Observatory of Belgium)
Last update : 2021-09-13 08:42:22 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
- 1.9 – 147.7km
- Mean velocity, P wave
- 5.4km/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: 9 measurements, root-mean-square deviation 0.32 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)9 stations | |||||
| LESLessines | 1.9 | 0 | 11:43:46.37+0.21 s | 11:43:46.73+0.57 s | 0.36 |
| SKQSteenkerque | 17.5 | 106 | 11:43:49.14+2.98 s | 11:43:51.77+5.61 s | 2.63 |
| RQRRonquières | 28.7 | 110 | 11:43:50.97+4.81 s | – | – |
| BRQBracquegnies | 31.5 | 139 | 11:43:52.25+6.09 s | – | – |
| SNFSeneffe | 37.3 | 123 | 11:43:52.96+6.80 s | 11:43:57.36+11.20 s | 4.40 |
| TGATangissart | 49.0 | 101 | 11:43:54.58+8.42 s | – | – |
| DSLBDessel | 104.7 | 55 | 11:44:04.79+18.63 s | – | – |
| CLAClavier | 107.8 | 106 | 11:44:06.19+20.03 s | – | – |
| RCHRochefort | 115.2 | 121 | 11:44:07.49+21.33 s | – | – |
| Dutch seismic network (KNMI)1 station | |||||
| HGNHeimansgroeve | 147.7 | 86 | 11:44:11.34+25.18 s | – | – |