WUPPERTAL (DE)
Quarry blast30 April 2021
- Magnitude
- 1.8ML
- Depth
- –
- Belgian time
- 09:57:042021-04-30
- UTC
- 07:57:042021-04-30
Main parameters
| Date and time | 2021-04-30 07:57:04 UTC 2021-04-30 09:57:04 Belgian time |
|---|---|
| Magnitude | ML 1.8 |
| Epicentral coordinates | 51.213° N, 7.104° E Uncertainty ± 2.9 km |
| Event ID | ROB 13285 |
Data source : ROB (Royal Observatory of Belgium)
Last update : 2021-04-30 16:00:56 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
- 5
- Epicentral distance
- 96.3 – 142.4km
- Mean velocity, P wave
- 4.9km/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: 4 measurements, root-mean-square deviation 0.19 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)3 stations | |||||
| MEMHMembach | 102.2 | 229 | 07:57:21.70+17.62 s | – | – |
| MRGMont Rigi | 106.6 | 223 | 07:57:22.24+18.16 s | 07:57:34.94+30.86 s | 12.70 |
| KLBKalborn | 142.4 | 210 | 07:57:27.15+23.07 s | 07:57:44.82+40.74 s | 17.67 |
| Dutch seismic network (KNMI)2 stations | |||||
| HGNHeimansgroeve | 96.3 | 239 | 07:57:20.33+16.25 s | 07:57:32.77+28.69 s | 12.44 |
| TERZTerziet | 98.3 | 239 | 07:57:20.41+16.33 s | 07:57:34.28+30.20 s | 13.87 |