WUELFRATH (DE)
Quarry blast18 August 2020
- Magnitude
- 2.1ML
- Depth
- –
- Belgian time
- 09:05:092020-08-18
- UTC
- 07:05:092020-08-18
Main parameters
| Date and time | 2020-08-18 07:05:09 UTC 2020-08-18 09:05:09 Belgian time |
|---|---|
| Magnitude | ML 2.1 |
| Epicentral coordinates | 51.285° N, 7.048° E Uncertainty ± 1.2 km |
| Event ID | ROB 10690 |
Data source : ROB (Royal Observatory of Belgium)
Last update : 2020-08-18 09:39:01 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
- 77.7 – 147.6km
- Mean velocity, P wave
- 6.9km/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: 5 measurements, root-mean-square deviation 0.73 s. S wave: 5 measurements, root-mean-square deviation 0.35 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)5 stations | |||||
| MEMHMembach | 104.8 | 225 | 07:05:27.00+17.95 s | 07:05:40.53+31.48 s | 13.53 |
| MRGMont Rigi | 110.0 | 219 | 07:05:27.15+18.10 s | 07:05:42.33+33.28 s | 15.18 |
| HOUHouvegnez | 127.0 | 216 | 07:05:30.49+21.44 s | 07:05:46.68+37.63 s | 16.19 |
| DSLBDessel | 138.6 | 268 | 07:05:32.67+23.62 s | 07:05:49.59+40.54 s | 16.92 |
| KLBKalborn | 147.6 | 207 | 07:05:33.44+24.39 s | 07:05:51.53+42.48 s | 18.09 |
| Dutch seismic network (KNMI)3 stations | |||||
| WTSBWinterswijk New | 77.7 | 347 | 07:05:22.97+13.92 s | 07:05:32.65+23.60 s | 9.68 |
| HGNHeimansgroeve | 97.5 | 234 | 07:05:24.82+15.77 s | 07:05:39.28+30.23 s | 14.46 |
| VKBValkenburg | 100.0 | 243 | 07:05:24.33+15.28 s | 07:05:39.57+30.52 s | 15.24 |