LESSINES (BE)
Quarry blast9 September 2020
- Magnitude
- 1.6ML
- Depth
- –
- Belgian time
- 12:40:202020-09-09
- UTC
- 10:40:202020-09-09
Main parameters
| Date and time | 2020-09-09 10:40:20 UTC 2020-09-09 12:40:20 Belgian time |
|---|---|
| Magnitude | ML 1.6 |
| Epicentral coordinates | 50.713° N, 3.861° E Uncertainty ± 2.3 km |
| Event ID | ROB 10825 |
Data source : ROB (Royal Observatory of Belgium)
Last update : 2020-09-09 14:53:42 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
- 9
- Epicentral distance
- 1.3 – 152.4km
- 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: 7 measurements, root-mean-square deviation 0.29 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 | 1.3 | 260 | 10:40:20.92+0.21 s | 10:40:21.12+0.41 s | 0.20 |
| SKQSteenkerque | 17.1 | 115 | 10:40:23.49+2.78 s | 10:40:26.02+5.31 s | 2.53 |
| RQRRonquières | 28.4 | 115 | 10:40:25.14+4.43 s | – | – |
| BRQBracquegnies | 32.4 | 143 | 10:40:26.51+5.80 s | – | – |
| BOUBougnies | 36.5 | 171 | 10:40:26.88+6.17 s | – | – |
| TGATangissart | 48.3 | 104 | 10:40:29.72+9.01 s | – | – |
| DOUDourbes | 86.3 | 142 | 10:40:36.10+15.39 s | 10:40:46.84+26.13 s | 10.74 |
| MEMSMembach | 152.4 | 94 | 10:40:46.39+25.68 s | – | – |
| MEMHMembach | 152.4 | 94 | 10:40:46.50+25.79 s | 10:41:05.75+45.04 s | 19.25 |