DEUX-ACREN (BE)
Quarry blast4 May 2018
- Magnitude
- 1.8ML
- Depth
- 2.9km ± 3.1
- Belgian time
- 11:38:192018-05-04
- UTC
- 09:38:192018-05-04
Main parameters
| Date and time | 2018-05-04 09:38:19 UTC 2018-05-04 11:38:19 Belgian time |
|---|---|
| Magnitude | ML 1.8 |
| Epicentral coordinates | 50.736° N, 3.856° E Uncertainty ± 2.9 km |
| Depth of hypocenter | 2.9 ± 3.1 km |
| Event ID | ROB 6570 |
Data source : ROB (Royal Observatory of Belgium)
Last update : 2018-05-04 14:45:16 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
- 10
- Epicentral distance
- 3.0 – 158.1km
- Mean velocity, P wave
- 5.7km/s
- Mean velocity, S wave
- 3.4km/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. Hypocenter at a depth of 2.9 km. P wave: 7 measurements, root-mean-square deviation 0.32 s. S wave: 5 measurements, root-mean-square deviation 0.22 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 | nm | |
|---|---|---|---|---|---|---|
| Belgian seismic network (Royal Observatory of Belgium)10 stations | ||||||
| LESLessines | 3.0 | 198 | 09:38:20.22+0.66 s | – | – | – |
| SKQSteenkerque | 18.6 | 122 | 09:38:22.88+3.32 s | 09:38:24.90+5.34 s | 2.02 | 163.5 |
| RQRRonquières | 29.8 | 119 | 09:38:24.81+5.25 s | 09:38:28.12+8.56 s | 3.31 | – |
| BRQBracquegnies | 34.6 | 145 | 09:38:25.86+6.30 s | – | – | – |
| DOUDourbes | 88.6 | 143 | 09:38:35.59+16.03 s | 09:38:45.04+25.48 s | 9.45 | 11.1 |
| GESGesves | 95.6 | 114 | 09:38:36.32+16.76 s | 09:38:47.63+28.07 s | 11.31 | – |
| CLAClavier | 108.3 | 108 | 09:38:37.91+18.35 s | 09:38:51.32+31.76 s | 13.41 | – |
| LCHLa Chartreuse | 123.6 | 94 | 09:38:39.86+20.30 s | – | – | – |
| MEMHMembach | 152.9 | 94 | 09:38:44.35+24.79 s | – | – | – |
| HOUHouvegnez | 158.1 | 105 | 09:38:45.60+26.04 s | 09:39:04.85+45.29 s | 19.25 | – |