TOURNAI (BE)
Quarry blast27 January 2020
- Magnitude
- 1.8ML
- Depth
- 9.6km ± 4.9
- Belgian time
- 12:30:532020-01-27
- UTC
- 11:30:532020-01-27
Main parameters
| Date and time | 2020-01-27 11:30:53 UTC 2020-01-27 12:30:53 Belgian time |
|---|---|
| Magnitude | ML 1.8 |
| Epicentral coordinates | 50.663° N, 3.432° E Uncertainty ± 3.8 km |
| Depth of hypocenter | 9.6 ± 4.9 km |
| Event ID | ROB 9185 |
Data source : ROB (Royal Observatory of Belgium)
Last update : 2020-01-27 12:56:37 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
- 13
- Epicentral distance
- 29.5 – 185.7km
- Mean velocity, P wave
- 6.0km/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 9.6 km. P wave: 9 measurements, root-mean-square deviation 0.46 s. S wave: 5 measurements, root-mean-square deviation 0.69 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)13 stations | ||||||
| LESLessines | 29.5 | 80 | 11:30:59.52+5.66 s | 11:31:03.50+9.64 s | 3.98 | 56.7 |
| SKQSteenkerque | 45.9 | 92 | 11:31:01.67+7.81 s | 11:31:07.07+13.21 s | 5.40 | – |
| BOUBougnies | 47.5 | 130 | 11:31:01.46+7.60 s | – | – | – |
| BRQBracquegnies | 53.8 | 112 | 11:31:02.85+8.99 s | – | – | – |
| RQRRonquières | 56.5 | 96 | 11:31:03.23+9.37 s | – | – | – |
| OSTBOostende | 72.7 | 332 | 11:31:06.90+13.04 s | – | – | – |
| TGATangissart | 77.4 | 94 | 11:31:06.02+12.16 s | 11:31:15.74+21.88 s | 9.72 | – |
| MRDMaredsous | 103.0 | 112 | 11:31:11.00+17.14 s | 11:31:25.10+31.24 s | 14.10 | – |
| DOUDourbes | 104.1 | 127 | 11:31:11.28+17.42 s | 11:31:24.92+31.06 s | 13.64 | – |
| GESGesves | 121.4 | 104 | 11:31:13.54+19.68 s | – | – | – |
| CLAClavier | 135.3 | 101 | 11:31:16.30+22.44 s | 11:31:34.40+40.54 s | 18.10 | – |
| RCHRochefort | 139.6 | 113 | 11:31:16.37+22.51 s | – | – | – |
| HOUHouvegnez | 185.7 | 100 | 11:31:24.41+30.55 s | – | – | – |