NAMUR (BE)
Quarry blast25 August 2020
- Magnitude
- 1.9ML
- Depth
- –
- Belgian time
- 13:43:342020-08-25
- UTC
- 11:43:342020-08-25
Main parameters
| Date and time | 2020-08-25 11:43:34 UTC 2020-08-25 13:43:34 Belgian time |
|---|---|
| Magnitude | ML 1.9 |
| Epicentral coordinates | 50.499° N, 4.976° E Uncertainty ± 2.0 km |
| Event ID | ROB 10735 |
Data source : ROB (Royal Observatory of Belgium)
Last update : 2020-08-26 09:41:42 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
- 7
- Epicentral distance
- 26.5 – 92.1km
- Mean velocity, P wave
- 6.1km/s
- Mean velocity, S wave
- 3.5km/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 0.44 s. S wave: 5 measurements, root-mean-square deviation 0.54 s.
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)6 stations | |||||
| MRDMaredsous | 26.5 | 214 | 11:43:39.26+4.37 s | 11:43:44.02+9.13 s | 4.76 |
| DOUDourbes | 52.5 | 211 | 11:43:43.89+9.00 s | 11:43:51.05+16.16 s | 7.16 |
| RQRRonquières | 54.5 | 283 | 11:43:44.51+9.62 s | – | – |
| SKQSteenkerque | 65.6 | 285 | 11:43:45.83+10.94 s | – | – |
| MEMHMembach | 74.3 | 80 | 11:43:47.97+13.08 s | 11:43:57.54+22.65 s | 9.57 |
| KLBKalborn | 92.1 | 118 | 11:43:51.30+16.41 s | 11:44:01.42+26.53 s | 10.12 |
| Dutch seismic network (KNMI)1 station | |||||
| HGNHeimansgroeve | 73.7 | 66 | 11:43:47.48+12.59 s | 11:43:56.84+21.95 s | 9.36 |