ALTRICH (DE)
Suspected quarry blast20 August 2020
- Magnitude
- 2.2ML
- Depth
- –
- Belgian time
- 10:20:562020-08-20
- UTC
- 08:20:562020-08-20
Main parameters
| Date and time | 2020-08-20 08:20:56 UTC 2020-08-20 10:20:56 Belgian time |
|---|---|
| Magnitude | ML 2.2 |
| Epicentral coordinates | 49.941° N, 6.894° E Uncertainty ± 1.1 km |
| Event ID | ROB 10710 |
Data source : ROB (Royal Observatory of Belgium)
Last update : 2020-08-20 18:49:47 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
- 11
- Epicentral distance
- 59.0 – 165.6km
- Mean velocity, P wave
- 5.5km/s
- Mean velocity, S wave
- 3.3km/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: 5 measurements, root-mean-square deviation 0.23 s. S wave: 4 measurements, root-mean-square deviation 0.15 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 | |||||
| KLBKalborn | 59.0 | 288 | 08:21:07.07+10.82 s | 08:21:13.86+17.61 s | 6.79 |
| HOUHouvegnez | 78.4 | 306 | 08:21:09.98+13.73 s | – | – |
| MRGMont Rigi | 86.2 | 318 | 08:21:11.67+15.42 s | 08:21:22.07+25.82 s | 10.40 |
| MEMHMembach | 97.4 | 320 | 08:21:14.02+17.77 s | 08:21:25.17+28.92 s | 11.15 |
| RCHRochefort | 121.7 | 282 | 08:21:17.47+21.22 s | 08:21:32.79+36.54 s | 15.32 |
| CLAClavier | 125.5 | 296 | 08:21:18.68+22.43 s | 08:21:34.28+38.03 s | 15.60 |
| EBNEben-Emael | 128.6 | 318 | 08:21:19.21+22.96 s | – | – |
| GESGesves | 138.2 | 292 | 08:21:20.32+24.07 s | – | – |
| DOUDourbes | 165.6 | 277 | 08:21:23.68+27.43 s | 08:21:42.84+46.59 s | 19.16 |
| Dutch seismic network (KNMI)2 stations | |||||
| HGNHeimansgroeve | 114.3 | 324 | 08:21:16.83+20.58 s | 08:21:30.67+34.42 s | 13.84 |
| VKBValkenburg | 129.7 | 323 | 08:21:19.29+23.04 s | 08:21:35.52+39.27 s | 16.23 |